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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 16:40:20 -0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 16:40:20 -0400
commitdc690d8ef842b464f1c429a376ca16cb8dbee6ae (patch)
tree77955849af5a15755f5e55e24ae4b9c520583a72 /fs
parent57399ec9077a4b962b81037aaa279fab52f5e989 (diff)
parent91a6902958f052358899f58683d44e36228d85c2 (diff)
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (61 commits) sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes sysfs: make directory dentries and inodes reclaimable sysfs: implement sysfs_get_dentry() sysfs: move sysfs_drop_dentry() to dir.c and make it static sysfs: restructure add/remove paths and fix inode update sysfs: use sysfs_mutex to protect the sysfs_dirent tree sysfs: consolidate sysfs spinlocks sysfs: make kobj point to sysfs_dirent instead of dentry sysfs: implement sysfs_find_dirent() and sysfs_get_dirent() sysfs: implement SYSFS_FLAG_REMOVED flag sysfs: rename sysfs_dirent->s_type to s_flags and make room for flags sysfs: make sysfs_drop_dentry() access inodes using ilookup() sysfs: Fix oops in sysfs_drop_dentry on x86_64 sysfs: use singly-linked list for sysfs_dirent tree sysfs: slim down sysfs_dirent->s_active sysfs: move s_active functions to fs/sysfs/dir.c sysfs: fix root sysfs_dirent -> root dentry association sysfs: use iget_locked() instead of new_inode() sysfs: reorganize sysfs_new_indoe() and sysfs_create() sysfs: fix parent refcounting during rename and move ...
Diffstat (limited to 'fs')
-rw-r--r--fs/debugfs/inode.c63
-rw-r--r--fs/ecryptfs/main.c2
-rw-r--r--fs/ocfs2/cluster/masklog.c1
-rw-r--r--fs/partitions/check.c1
-rw-r--r--fs/sysfs/bin.c195
-rw-r--r--fs/sysfs/dir.c1297
-rw-r--r--fs/sysfs/file.c379
-rw-r--r--fs/sysfs/group.c55
-rw-r--r--fs/sysfs/inode.c221
-rw-r--r--fs/sysfs/mount.c36
-rw-r--r--fs/sysfs/symlink.c150
-rw-r--r--fs/sysfs/sysfs.h169
12 files changed, 1563 insertions, 1006 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index ec8896b264de..1d533a2ec3a6 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -368,6 +368,69 @@ void debugfs_remove(struct dentry *dentry)
368} 368}
369EXPORT_SYMBOL_GPL(debugfs_remove); 369EXPORT_SYMBOL_GPL(debugfs_remove);
370 370
371/**
372 * debugfs_rename - rename a file/directory in the debugfs filesystem
373 * @old_dir: a pointer to the parent dentry for the renamed object. This
374 * should be a directory dentry.
375 * @old_dentry: dentry of an object to be renamed.
376 * @new_dir: a pointer to the parent dentry where the object should be
377 * moved. This should be a directory dentry.
378 * @new_name: a pointer to a string containing the target name.
379 *
380 * This function renames a file/directory in debugfs. The target must not
381 * exist for rename to succeed.
382 *
383 * This function will return a pointer to old_dentry (which is updated to
384 * reflect renaming) if it succeeds. If an error occurs, %NULL will be
385 * returned.
386 *
387 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
388 * returned.
389 */
390struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
391 struct dentry *new_dir, const char *new_name)
392{
393 int error;
394 struct dentry *dentry = NULL, *trap;
395 const char *old_name;
396
397 trap = lock_rename(new_dir, old_dir);
398 /* Source or destination directories don't exist? */
399 if (!old_dir->d_inode || !new_dir->d_inode)
400 goto exit;
401 /* Source does not exist, cyclic rename, or mountpoint? */
402 if (!old_dentry->d_inode || old_dentry == trap ||
403 d_mountpoint(old_dentry))
404 goto exit;
405 dentry = lookup_one_len(new_name, new_dir, strlen(new_name));
406 /* Lookup failed, cyclic rename or target exists? */
407 if (IS_ERR(dentry) || dentry == trap || dentry->d_inode)
408 goto exit;
409
410 old_name = fsnotify_oldname_init(old_dentry->d_name.name);
411
412 error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode,
413 dentry);
414 if (error) {
415 fsnotify_oldname_free(old_name);
416 goto exit;
417 }
418 d_move(old_dentry, dentry);
419 fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name,
420 old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode),
421 NULL, old_dentry->d_inode);
422 fsnotify_oldname_free(old_name);
423 unlock_rename(new_dir, old_dir);
424 dput(dentry);
425 return old_dentry;
426exit:
427 if (dentry && !IS_ERR(dentry))
428 dput(dentry);
429 unlock_rename(new_dir, old_dir);
430 return NULL;
431}
432EXPORT_SYMBOL_GPL(debugfs_rename);
433
371static decl_subsys(debug, NULL, NULL); 434static decl_subsys(debug, NULL, NULL);
372 435
373static int __init debugfs_init(void) 436static int __init debugfs_init(void)
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index 606128f5c927..02ca6f1e55d7 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -840,8 +840,6 @@ static int __init ecryptfs_init(void)
840 goto out; 840 goto out;
841 } 841 }
842 kobj_set_kset_s(&ecryptfs_subsys, fs_subsys); 842 kobj_set_kset_s(&ecryptfs_subsys, fs_subsys);
843 sysfs_attr_version.attr.owner = THIS_MODULE;
844 sysfs_attr_version_str.attr.owner = THIS_MODULE;
845 rc = do_sysfs_registration(); 843 rc = do_sysfs_registration();
846 if (rc) { 844 if (rc) {
847 printk(KERN_ERR "sysfs registration failed\n"); 845 printk(KERN_ERR "sysfs registration failed\n");
diff --git a/fs/ocfs2/cluster/masklog.c b/fs/ocfs2/cluster/masklog.c
index 2b205f5d5790..e9e042b93dbf 100644
--- a/fs/ocfs2/cluster/masklog.c
+++ b/fs/ocfs2/cluster/masklog.c
@@ -74,7 +74,6 @@ struct mlog_attribute {
74#define define_mask(_name) { \ 74#define define_mask(_name) { \
75 .attr = { \ 75 .attr = { \
76 .name = #_name, \ 76 .name = #_name, \
77 .owner = THIS_MODULE, \
78 .mode = S_IRUGO | S_IWUSR, \ 77 .mode = S_IRUGO | S_IWUSR, \
79 }, \ 78 }, \
80 .mask = ML_##_name, \ 79 .mask = ML_##_name, \
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 9a3a058f3553..98e0b85a9bb2 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -397,7 +397,6 @@ void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len,
397 static struct attribute addpartattr = { 397 static struct attribute addpartattr = {
398 .name = "whole_disk", 398 .name = "whole_disk",
399 .mode = S_IRUSR | S_IRGRP | S_IROTH, 399 .mode = S_IRUSR | S_IRGRP | S_IROTH,
400 .owner = THIS_MODULE,
401 }; 400 };
402 401
403 sysfs_create_file(&p->kobj, &addpartattr); 402 sysfs_create_file(&p->kobj, &addpartattr);
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index d3b9f5f07db1..135353f8a296 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -20,29 +20,41 @@
20 20
21#include "sysfs.h" 21#include "sysfs.h"
22 22
23struct bin_buffer {
24 struct mutex mutex;
25 void *buffer;
26 int mmapped;
27};
28
23static int 29static int
24fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count) 30fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
25{ 31{
26 struct bin_attribute * attr = to_bin_attr(dentry); 32 struct sysfs_dirent *attr_sd = dentry->d_fsdata;
27 struct kobject * kobj = to_kobj(dentry->d_parent); 33 struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
34 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
35 int rc;
36
37 /* need attr_sd for attr, its parent for kobj */
38 if (!sysfs_get_active_two(attr_sd))
39 return -ENODEV;
28 40
29 if (!attr->read) 41 rc = -EIO;
30 return -EIO; 42 if (attr->read)
43 rc = attr->read(kobj, attr, buffer, off, count);
31 44
32 return attr->read(kobj, buffer, off, count); 45 sysfs_put_active_two(attr_sd);
46
47 return rc;
33} 48}
34 49
35static ssize_t 50static ssize_t
36read(struct file * file, char __user * userbuf, size_t count, loff_t * off) 51read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
37{ 52{
38 char *buffer = file->private_data; 53 struct bin_buffer *bb = file->private_data;
39 struct dentry *dentry = file->f_path.dentry; 54 struct dentry *dentry = file->f_path.dentry;
40 int size = dentry->d_inode->i_size; 55 int size = dentry->d_inode->i_size;
41 loff_t offs = *off; 56 loff_t offs = *off;
42 int ret; 57 int count = min_t(size_t, bytes, PAGE_SIZE);
43
44 if (count > PAGE_SIZE)
45 count = PAGE_SIZE;
46 58
47 if (size) { 59 if (size) {
48 if (offs > size) 60 if (offs > size)
@@ -51,43 +63,56 @@ read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
51 count = size - offs; 63 count = size - offs;
52 } 64 }
53 65
54 ret = fill_read(dentry, buffer, offs, count); 66 mutex_lock(&bb->mutex);
55 if (ret < 0) 67
56 return ret; 68 count = fill_read(dentry, bb->buffer, offs, count);
57 count = ret; 69 if (count < 0)
70 goto out_unlock;
58 71
59 if (copy_to_user(userbuf, buffer, count)) 72 if (copy_to_user(userbuf, bb->buffer, count)) {
60 return -EFAULT; 73 count = -EFAULT;
74 goto out_unlock;
75 }
61 76
62 pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count); 77 pr_debug("offs = %lld, *off = %lld, count = %d\n", offs, *off, count);
63 78
64 *off = offs + count; 79 *off = offs + count;
65 80
81 out_unlock:
82 mutex_unlock(&bb->mutex);
66 return count; 83 return count;
67} 84}
68 85
69static int 86static int
70flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count) 87flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
71{ 88{
72 struct bin_attribute *attr = to_bin_attr(dentry); 89 struct sysfs_dirent *attr_sd = dentry->d_fsdata;
73 struct kobject *kobj = to_kobj(dentry->d_parent); 90 struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
91 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
92 int rc;
93
94 /* need attr_sd for attr, its parent for kobj */
95 if (!sysfs_get_active_two(attr_sd))
96 return -ENODEV;
97
98 rc = -EIO;
99 if (attr->write)
100 rc = attr->write(kobj, attr, buffer, offset, count);
74 101
75 if (!attr->write) 102 sysfs_put_active_two(attr_sd);
76 return -EIO;
77 103
78 return attr->write(kobj, buffer, offset, count); 104 return rc;
79} 105}
80 106
81static ssize_t write(struct file * file, const char __user * userbuf, 107static ssize_t write(struct file *file, const char __user *userbuf,
82 size_t count, loff_t * off) 108 size_t bytes, loff_t *off)
83{ 109{
84 char *buffer = file->private_data; 110 struct bin_buffer *bb = file->private_data;
85 struct dentry *dentry = file->f_path.dentry; 111 struct dentry *dentry = file->f_path.dentry;
86 int size = dentry->d_inode->i_size; 112 int size = dentry->d_inode->i_size;
87 loff_t offs = *off; 113 loff_t offs = *off;
114 int count = min_t(size_t, bytes, PAGE_SIZE);
88 115
89 if (count > PAGE_SIZE)
90 count = PAGE_SIZE;
91 if (size) { 116 if (size) {
92 if (offs > size) 117 if (offs > size)
93 return 0; 118 return 0;
@@ -95,72 +120,100 @@ static ssize_t write(struct file * file, const char __user * userbuf,
95 count = size - offs; 120 count = size - offs;
96 } 121 }
97 122
98 if (copy_from_user(buffer, userbuf, count)) 123 mutex_lock(&bb->mutex);
99 return -EFAULT;
100 124
101 count = flush_write(dentry, buffer, offs, count); 125 if (copy_from_user(bb->buffer, userbuf, count)) {
126 count = -EFAULT;
127 goto out_unlock;
128 }
129
130 count = flush_write(dentry, bb->buffer, offs, count);
102 if (count > 0) 131 if (count > 0)
103 *off = offs + count; 132 *off = offs + count;
133
134 out_unlock:
135 mutex_unlock(&bb->mutex);
104 return count; 136 return count;
105} 137}
106 138
107static int mmap(struct file *file, struct vm_area_struct *vma) 139static int mmap(struct file *file, struct vm_area_struct *vma)
108{ 140{
109 struct dentry *dentry = file->f_path.dentry; 141 struct bin_buffer *bb = file->private_data;
110 struct bin_attribute *attr = to_bin_attr(dentry); 142 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
111 struct kobject *kobj = to_kobj(dentry->d_parent); 143 struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
144 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
145 int rc;
146
147 mutex_lock(&bb->mutex);
148
149 /* need attr_sd for attr, its parent for kobj */
150 if (!sysfs_get_active_two(attr_sd))
151 return -ENODEV;
112 152
113 if (!attr->mmap) 153 rc = -EINVAL;
114 return -EINVAL; 154 if (attr->mmap)
155 rc = attr->mmap(kobj, attr, vma);
115 156
116 return attr->mmap(kobj, attr, vma); 157 if (rc == 0 && !bb->mmapped)
158 bb->mmapped = 1;
159 else
160 sysfs_put_active_two(attr_sd);
161
162 mutex_unlock(&bb->mutex);
163
164 return rc;
117} 165}
118 166
119static int open(struct inode * inode, struct file * file) 167static int open(struct inode * inode, struct file * file)
120{ 168{
121 struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent); 169 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
122 struct bin_attribute * attr = to_bin_attr(file->f_path.dentry); 170 struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
123 int error = -EINVAL; 171 struct bin_buffer *bb = NULL;
124 172 int error;
125 if (!kobj || !attr)
126 goto Done;
127 173
128 /* Grab the module reference for this attribute if we have one */ 174 /* need attr_sd for attr */
129 error = -ENODEV; 175 if (!sysfs_get_active(attr_sd))
130 if (!try_module_get(attr->attr.owner)) 176 return -ENODEV;
131 goto Done;
132 177
133 error = -EACCES; 178 error = -EACCES;
134 if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap)) 179 if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
135 goto Error; 180 goto err_out;
136 if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap)) 181 if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
137 goto Error; 182 goto err_out;
138 183
139 error = -ENOMEM; 184 error = -ENOMEM;
140 file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL); 185 bb = kzalloc(sizeof(*bb), GFP_KERNEL);
141 if (!file->private_data) 186 if (!bb)
142 goto Error; 187 goto err_out;
143 188
144 error = 0; 189 bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
145 goto Done; 190 if (!bb->buffer)
146 191 goto err_out;
147 Error: 192
148 module_put(attr->attr.owner); 193 mutex_init(&bb->mutex);
149 Done: 194 file->private_data = bb;
150 if (error) 195
151 kobject_put(kobj); 196 /* open succeeded, put active reference and pin attr_sd */
197 sysfs_put_active(attr_sd);
198 sysfs_get(attr_sd);
199 return 0;
200
201 err_out:
202 sysfs_put_active(attr_sd);
203 kfree(bb);
152 return error; 204 return error;
153} 205}
154 206
155static int release(struct inode * inode, struct file * file) 207static int release(struct inode * inode, struct file * file)
156{ 208{
157 struct kobject * kobj = to_kobj(file->f_path.dentry->d_parent); 209 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
158 struct bin_attribute * attr = to_bin_attr(file->f_path.dentry); 210 struct bin_buffer *bb = file->private_data;
159 u8 * buffer = file->private_data; 211
160 212 if (bb->mmapped)
161 kobject_put(kobj); 213 sysfs_put_active_two(attr_sd);
162 module_put(attr->attr.owner); 214 sysfs_put(attr_sd);
163 kfree(buffer); 215 kfree(bb->buffer);
216 kfree(bb);
164 return 0; 217 return 0;
165} 218}
166 219
@@ -181,9 +234,9 @@ const struct file_operations bin_fops = {
181 234
182int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr) 235int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
183{ 236{
184 BUG_ON(!kobj || !kobj->dentry || !attr); 237 BUG_ON(!kobj || !kobj->sd || !attr);
185 238
186 return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR); 239 return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
187} 240}
188 241
189 242
@@ -195,7 +248,7 @@ int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
195 248
196void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr) 249void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
197{ 250{
198 if (sysfs_hash_and_remove(kobj->dentry, attr->attr.name) < 0) { 251 if (sysfs_hash_and_remove(kobj->sd, attr->attr.name) < 0) {
199 printk(KERN_ERR "%s: " 252 printk(KERN_ERR "%s: "
200 "bad dentry or inode or no such file: \"%s\"\n", 253 "bad dentry or inode or no such file: \"%s\"\n",
201 __FUNCTION__, attr->attr.name); 254 __FUNCTION__, attr->attr.name);
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index c4342a019972..aee966c44aac 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -9,21 +9,337 @@
9#include <linux/module.h> 9#include <linux/module.h>
10#include <linux/kobject.h> 10#include <linux/kobject.h>
11#include <linux/namei.h> 11#include <linux/namei.h>
12#include <linux/idr.h>
13#include <linux/completion.h>
12#include <asm/semaphore.h> 14#include <asm/semaphore.h>
13#include "sysfs.h" 15#include "sysfs.h"
14 16
15DECLARE_RWSEM(sysfs_rename_sem); 17DEFINE_MUTEX(sysfs_mutex);
16spinlock_t sysfs_lock = SPIN_LOCK_UNLOCKED; 18spinlock_t sysfs_assoc_lock = SPIN_LOCK_UNLOCKED;
19
20static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED;
21static DEFINE_IDA(sysfs_ino_ida);
22
23/**
24 * sysfs_link_sibling - link sysfs_dirent into sibling list
25 * @sd: sysfs_dirent of interest
26 *
27 * Link @sd into its sibling list which starts from
28 * sd->s_parent->s_children.
29 *
30 * Locking:
31 * mutex_lock(sysfs_mutex)
32 */
33void sysfs_link_sibling(struct sysfs_dirent *sd)
34{
35 struct sysfs_dirent *parent_sd = sd->s_parent;
36
37 BUG_ON(sd->s_sibling);
38 sd->s_sibling = parent_sd->s_children;
39 parent_sd->s_children = sd;
40}
41
42/**
43 * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list
44 * @sd: sysfs_dirent of interest
45 *
46 * Unlink @sd from its sibling list which starts from
47 * sd->s_parent->s_children.
48 *
49 * Locking:
50 * mutex_lock(sysfs_mutex)
51 */
52void sysfs_unlink_sibling(struct sysfs_dirent *sd)
53{
54 struct sysfs_dirent **pos;
55
56 for (pos = &sd->s_parent->s_children; *pos; pos = &(*pos)->s_sibling) {
57 if (*pos == sd) {
58 *pos = sd->s_sibling;
59 sd->s_sibling = NULL;
60 break;
61 }
62 }
63}
64
65/**
66 * sysfs_get_dentry - get dentry for the given sysfs_dirent
67 * @sd: sysfs_dirent of interest
68 *
69 * Get dentry for @sd. Dentry is looked up if currently not
70 * present. This function climbs sysfs_dirent tree till it
71 * reaches a sysfs_dirent with valid dentry attached and descends
72 * down from there looking up dentry for each step.
73 *
74 * LOCKING:
75 * Kernel thread context (may sleep)
76 *
77 * RETURNS:
78 * Pointer to found dentry on success, ERR_PTR() value on error.
79 */
80struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
81{
82 struct sysfs_dirent *cur;
83 struct dentry *parent_dentry, *dentry;
84 int i, depth;
85
86 /* Find the first parent which has valid s_dentry and get the
87 * dentry.
88 */
89 mutex_lock(&sysfs_mutex);
90 restart0:
91 spin_lock(&sysfs_assoc_lock);
92 restart1:
93 spin_lock(&dcache_lock);
94
95 dentry = NULL;
96 depth = 0;
97 cur = sd;
98 while (!cur->s_dentry || !cur->s_dentry->d_inode) {
99 if (cur->s_flags & SYSFS_FLAG_REMOVED) {
100 dentry = ERR_PTR(-ENOENT);
101 depth = 0;
102 break;
103 }
104 cur = cur->s_parent;
105 depth++;
106 }
107 if (!IS_ERR(dentry))
108 dentry = dget_locked(cur->s_dentry);
109
110 spin_unlock(&dcache_lock);
111 spin_unlock(&sysfs_assoc_lock);
112
113 /* from the found dentry, look up depth times */
114 while (depth--) {
115 /* find and get depth'th ancestor */
116 for (cur = sd, i = 0; cur && i < depth; i++)
117 cur = cur->s_parent;
118
119 /* This can happen if tree structure was modified due
120 * to move/rename. Restart.
121 */
122 if (i != depth) {
123 dput(dentry);
124 goto restart0;
125 }
126
127 sysfs_get(cur);
128
129 mutex_unlock(&sysfs_mutex);
130
131 /* look it up */
132 parent_dentry = dentry;
133 dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
134 strlen(cur->s_name));
135 dput(parent_dentry);
136
137 if (IS_ERR(dentry)) {
138 sysfs_put(cur);
139 return dentry;
140 }
141
142 mutex_lock(&sysfs_mutex);
143 spin_lock(&sysfs_assoc_lock);
144
145 /* This, again, can happen if tree structure has
146 * changed and we looked up the wrong thing. Restart.
147 */
148 if (cur->s_dentry != dentry) {
149 dput(dentry);
150 sysfs_put(cur);
151 goto restart1;
152 }
153
154 spin_unlock(&sysfs_assoc_lock);
155
156 sysfs_put(cur);
157 }
158
159 mutex_unlock(&sysfs_mutex);
160 return dentry;
161}
162
163/**
164 * sysfs_get_active - get an active reference to sysfs_dirent
165 * @sd: sysfs_dirent to get an active reference to
166 *
167 * Get an active reference of @sd. This function is noop if @sd
168 * is NULL.
169 *
170 * RETURNS:
171 * Pointer to @sd on success, NULL on failure.
172 */
173struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
174{
175 if (unlikely(!sd))
176 return NULL;
177
178 while (1) {
179 int v, t;
180
181 v = atomic_read(&sd->s_active);
182 if (unlikely(v < 0))
183 return NULL;
184
185 t = atomic_cmpxchg(&sd->s_active, v, v + 1);
186 if (likely(t == v))
187 return sd;
188 if (t < 0)
189 return NULL;
190
191 cpu_relax();
192 }
193}
194
195/**
196 * sysfs_put_active - put an active reference to sysfs_dirent
197 * @sd: sysfs_dirent to put an active reference to
198 *
199 * Put an active reference to @sd. This function is noop if @sd
200 * is NULL.
201 */
202void sysfs_put_active(struct sysfs_dirent *sd)
203{
204 struct completion *cmpl;
205 int v;
206
207 if (unlikely(!sd))
208 return;
209
210 v = atomic_dec_return(&sd->s_active);
211 if (likely(v != SD_DEACTIVATED_BIAS))
212 return;
213
214 /* atomic_dec_return() is a mb(), we'll always see the updated
215 * sd->s_sibling.
216 */
217 cmpl = (void *)sd->s_sibling;
218 complete(cmpl);
219}
220
221/**
222 * sysfs_get_active_two - get active references to sysfs_dirent and parent
223 * @sd: sysfs_dirent of interest
224 *
225 * Get active reference to @sd and its parent. Parent's active
226 * reference is grabbed first. This function is noop if @sd is
227 * NULL.
228 *
229 * RETURNS:
230 * Pointer to @sd on success, NULL on failure.
231 */
232struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd)
233{
234 if (sd) {
235 if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent)))
236 return NULL;
237 if (unlikely(!sysfs_get_active(sd))) {
238 sysfs_put_active(sd->s_parent);
239 return NULL;
240 }
241 }
242 return sd;
243}
244
245/**
246 * sysfs_put_active_two - put active references to sysfs_dirent and parent
247 * @sd: sysfs_dirent of interest
248 *
249 * Put active references to @sd and its parent. This function is
250 * noop if @sd is NULL.
251 */
252void sysfs_put_active_two(struct sysfs_dirent *sd)
253{
254 if (sd) {
255 sysfs_put_active(sd);
256 sysfs_put_active(sd->s_parent);
257 }
258}
259
260/**
261 * sysfs_deactivate - deactivate sysfs_dirent
262 * @sd: sysfs_dirent to deactivate
263 *
264 * Deny new active references and drain existing ones.
265 */
266static void sysfs_deactivate(struct sysfs_dirent *sd)
267{
268 DECLARE_COMPLETION_ONSTACK(wait);
269 int v;
270
271 BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED));
272 sd->s_sibling = (void *)&wait;
273
274 /* atomic_add_return() is a mb(), put_active() will always see
275 * the updated sd->s_sibling.
276 */
277 v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active);
278
279 if (v != SD_DEACTIVATED_BIAS)
280 wait_for_completion(&wait);
281
282 sd->s_sibling = NULL;
283}
284
285static int sysfs_alloc_ino(ino_t *pino)
286{
287 int ino, rc;
288
289 retry:
290 spin_lock(&sysfs_ino_lock);
291 rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino);
292 spin_unlock(&sysfs_ino_lock);
293
294 if (rc == -EAGAIN) {
295 if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL))
296 goto retry;
297 rc = -ENOMEM;
298 }
299
300 *pino = ino;
301 return rc;
302}
303
304static void sysfs_free_ino(ino_t ino)
305{
306 spin_lock(&sysfs_ino_lock);
307 ida_remove(&sysfs_ino_ida, ino);
308 spin_unlock(&sysfs_ino_lock);
309}
310
311void release_sysfs_dirent(struct sysfs_dirent * sd)
312{
313 struct sysfs_dirent *parent_sd;
314
315 repeat:
316 /* Moving/renaming is always done while holding reference.
317 * sd->s_parent won't change beneath us.
318 */
319 parent_sd = sd->s_parent;
320
321 if (sysfs_type(sd) == SYSFS_KOBJ_LINK)
322 sysfs_put(sd->s_elem.symlink.target_sd);
323 if (sysfs_type(sd) & SYSFS_COPY_NAME)
324 kfree(sd->s_name);
325 kfree(sd->s_iattr);
326 sysfs_free_ino(sd->s_ino);
327 kmem_cache_free(sysfs_dir_cachep, sd);
328
329 sd = parent_sd;
330 if (sd && atomic_dec_and_test(&sd->s_count))
331 goto repeat;
332}
17 333
18static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) 334static void sysfs_d_iput(struct dentry * dentry, struct inode * inode)
19{ 335{
20 struct sysfs_dirent * sd = dentry->d_fsdata; 336 struct sysfs_dirent * sd = dentry->d_fsdata;
21 337
22 if (sd) { 338 if (sd) {
23 /* sd->s_dentry is protected with sysfs_lock. This 339 /* sd->s_dentry is protected with sysfs_assoc_lock.
24 * allows sysfs_drop_dentry() to dereference it. 340 * This allows sysfs_drop_dentry() to dereference it.
25 */ 341 */
26 spin_lock(&sysfs_lock); 342 spin_lock(&sysfs_assoc_lock);
27 343
28 /* The dentry might have been deleted or another 344 /* The dentry might have been deleted or another
29 * lookup could have happened updating sd->s_dentry to 345 * lookup could have happened updating sd->s_dentry to
@@ -32,7 +348,7 @@ static void sysfs_d_iput(struct dentry * dentry, struct inode * inode)
32 */ 348 */
33 if (sd->s_dentry == dentry) 349 if (sd->s_dentry == dentry)
34 sd->s_dentry = NULL; 350 sd->s_dentry = NULL;
35 spin_unlock(&sysfs_lock); 351 spin_unlock(&sysfs_assoc_lock);
36 sysfs_put(sd); 352 sysfs_put(sd);
37 } 353 }
38 iput(inode); 354 iput(inode);
@@ -42,260 +358,402 @@ static struct dentry_operations sysfs_dentry_ops = {
42 .d_iput = sysfs_d_iput, 358 .d_iput = sysfs_d_iput,
43}; 359};
44 360
45static unsigned int sysfs_inode_counter; 361struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type)
46ino_t sysfs_get_inum(void)
47{ 362{
48 if (unlikely(sysfs_inode_counter < 3)) 363 char *dup_name = NULL;
49 sysfs_inode_counter = 3; 364 struct sysfs_dirent *sd = NULL;
50 return sysfs_inode_counter++;
51}
52 365
53/* 366 if (type & SYSFS_COPY_NAME) {
54 * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent 367 name = dup_name = kstrdup(name, GFP_KERNEL);
55 */ 368 if (!name)
56static struct sysfs_dirent * __sysfs_new_dirent(void * element) 369 goto err_out;
57{ 370 }
58 struct sysfs_dirent * sd;
59 371
60 sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); 372 sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL);
61 if (!sd) 373 if (!sd)
62 return NULL; 374 goto err_out;
375
376 if (sysfs_alloc_ino(&sd->s_ino))
377 goto err_out;
63 378
64 sd->s_ino = sysfs_get_inum();
65 atomic_set(&sd->s_count, 1); 379 atomic_set(&sd->s_count, 1);
380 atomic_set(&sd->s_active, 0);
66 atomic_set(&sd->s_event, 1); 381 atomic_set(&sd->s_event, 1);
67 INIT_LIST_HEAD(&sd->s_children); 382
68 INIT_LIST_HEAD(&sd->s_sibling); 383 sd->s_name = name;
69 sd->s_element = element; 384 sd->s_mode = mode;
385 sd->s_flags = type;
70 386
71 return sd; 387 return sd;
388
389 err_out:
390 kfree(dup_name);
391 kmem_cache_free(sysfs_dir_cachep, sd);
392 return NULL;
72} 393}
73 394
74static void __sysfs_list_dirent(struct sysfs_dirent *parent_sd, 395/**
75 struct sysfs_dirent *sd) 396 * sysfs_attach_dentry - associate sysfs_dirent with dentry
397 * @sd: target sysfs_dirent
398 * @dentry: dentry to associate
399 *
400 * Associate @sd with @dentry. This is protected by
401 * sysfs_assoc_lock to avoid race with sysfs_d_iput().
402 *
403 * LOCKING:
404 * mutex_lock(sysfs_mutex)
405 */
406static void sysfs_attach_dentry(struct sysfs_dirent *sd, struct dentry *dentry)
76{ 407{
77 if (sd) 408 dentry->d_op = &sysfs_dentry_ops;
78 list_add(&sd->s_sibling, &parent_sd->s_children); 409 dentry->d_fsdata = sysfs_get(sd);
410
411 /* protect sd->s_dentry against sysfs_d_iput */
412 spin_lock(&sysfs_assoc_lock);
413 sd->s_dentry = dentry;
414 spin_unlock(&sysfs_assoc_lock);
415
416 d_rehash(dentry);
79} 417}
80 418
81static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent *parent_sd, 419static int sysfs_ilookup_test(struct inode *inode, void *arg)
82 void * element)
83{ 420{
84 struct sysfs_dirent *sd; 421 struct sysfs_dirent *sd = arg;
85 sd = __sysfs_new_dirent(element); 422 return inode->i_ino == sd->s_ino;
86 __sysfs_list_dirent(parent_sd, sd);
87 return sd;
88} 423}
89 424
90/* 425/**
426 * sysfs_addrm_start - prepare for sysfs_dirent add/remove
427 * @acxt: pointer to sysfs_addrm_cxt to be used
428 * @parent_sd: parent sysfs_dirent
91 * 429 *
92 * Return -EEXIST if there is already a sysfs element with the same name for 430 * This function is called when the caller is about to add or
93 * the same parent. 431 * remove sysfs_dirent under @parent_sd. This function acquires
432 * sysfs_mutex, grabs inode for @parent_sd if available and lock
433 * i_mutex of it. @acxt is used to keep and pass context to
434 * other addrm functions.
94 * 435 *
95 * called with parent inode's i_mutex held 436 * LOCKING:
437 * Kernel thread context (may sleep). sysfs_mutex is locked on
438 * return. i_mutex of parent inode is locked on return if
439 * available.
96 */ 440 */
97int sysfs_dirent_exist(struct sysfs_dirent *parent_sd, 441void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
98 const unsigned char *new) 442 struct sysfs_dirent *parent_sd)
99{ 443{
100 struct sysfs_dirent * sd; 444 struct inode *inode;
101 445
102 list_for_each_entry(sd, &parent_sd->s_children, s_sibling) { 446 memset(acxt, 0, sizeof(*acxt));
103 if (sd->s_element) { 447 acxt->parent_sd = parent_sd;
104 const unsigned char *existing = sysfs_get_name(sd);
105 if (strcmp(existing, new))
106 continue;
107 else
108 return -EEXIST;
109 }
110 }
111 448
112 return 0; 449 /* Lookup parent inode. inode initialization and I_NEW
450 * clearing are protected by sysfs_mutex. By grabbing it and
451 * looking up with _nowait variant, inode state can be
452 * determined reliably.
453 */
454 mutex_lock(&sysfs_mutex);
455
456 inode = ilookup5_nowait(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test,
457 parent_sd);
458
459 if (inode && !(inode->i_state & I_NEW)) {
460 /* parent inode available */
461 acxt->parent_inode = inode;
462
463 /* sysfs_mutex is below i_mutex in lock hierarchy.
464 * First, trylock i_mutex. If fails, unlock
465 * sysfs_mutex and lock them in order.
466 */
467 if (!mutex_trylock(&inode->i_mutex)) {
468 mutex_unlock(&sysfs_mutex);
469 mutex_lock(&inode->i_mutex);
470 mutex_lock(&sysfs_mutex);
471 }
472 } else
473 iput(inode);
113} 474}
114 475
476/**
477 * sysfs_add_one - add sysfs_dirent to parent
478 * @acxt: addrm context to use
479 * @sd: sysfs_dirent to be added
480 *
481 * Get @acxt->parent_sd and set sd->s_parent to it and increment
482 * nlink of parent inode if @sd is a directory. @sd is NOT
483 * linked into the children list of the parent. The caller
484 * should invoke sysfs_link_sibling() after this function
485 * completes if @sd needs to be on the children list.
486 *
487 * This function should be called between calls to
488 * sysfs_addrm_start() and sysfs_addrm_finish() and should be
489 * passed the same @acxt as passed to sysfs_addrm_start().
490 *
491 * LOCKING:
492 * Determined by sysfs_addrm_start().
493 */
494void sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
495{
496 sd->s_parent = sysfs_get(acxt->parent_sd);
497
498 if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
499 inc_nlink(acxt->parent_inode);
500
501 acxt->cnt++;
502}
115 503
116static struct sysfs_dirent * 504/**
117__sysfs_make_dirent(struct dentry *dentry, void *element, mode_t mode, int type) 505 * sysfs_remove_one - remove sysfs_dirent from parent
506 * @acxt: addrm context to use
507 * @sd: sysfs_dirent to be added
508 *
509 * Mark @sd removed and drop nlink of parent inode if @sd is a
510 * directory. @sd is NOT unlinked from the children list of the
511 * parent. The caller is repsonsible for removing @sd from the
512 * children list before calling this function.
513 *
514 * This function should be called between calls to
515 * sysfs_addrm_start() and sysfs_addrm_finish() and should be
516 * passed the same @acxt as passed to sysfs_addrm_start().
517 *
518 * LOCKING:
519 * Determined by sysfs_addrm_start().
520 */
521void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
118{ 522{
119 struct sysfs_dirent * sd; 523 BUG_ON(sd->s_sibling || (sd->s_flags & SYSFS_FLAG_REMOVED));
120 524
121 sd = __sysfs_new_dirent(element); 525 sd->s_flags |= SYSFS_FLAG_REMOVED;
122 if (!sd) 526 sd->s_sibling = acxt->removed;
123 goto out; 527 acxt->removed = sd;
124 528
125 sd->s_mode = mode; 529 if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
126 sd->s_type = type; 530 drop_nlink(acxt->parent_inode);
127 sd->s_dentry = dentry;
128 if (dentry) {
129 dentry->d_fsdata = sysfs_get(sd);
130 dentry->d_op = &sysfs_dentry_ops;
131 }
132 531
133out: 532 acxt->cnt++;
134 return sd;
135} 533}
136 534
137int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, 535/**
138 void * element, umode_t mode, int type) 536 * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent
537 * @sd: target sysfs_dirent
538 *
539 * Drop dentry for @sd. @sd must have been unlinked from its
540 * parent on entry to this function such that it can't be looked
541 * up anymore.
542 *
543 * @sd->s_dentry which is protected with sysfs_assoc_lock points
544 * to the currently associated dentry but we're not holding a
545 * reference to it and racing with dput(). Grab dcache_lock and
546 * verify dentry before dropping it. If @sd->s_dentry is NULL or
547 * dput() beats us, no need to bother.
548 */
549static void sysfs_drop_dentry(struct sysfs_dirent *sd)
139{ 550{
140 struct sysfs_dirent *sd; 551 struct dentry *dentry = NULL;
552 struct inode *inode;
553
554 /* We're not holding a reference to ->s_dentry dentry but the
555 * field will stay valid as long as sysfs_assoc_lock is held.
556 */
557 spin_lock(&sysfs_assoc_lock);
558 spin_lock(&dcache_lock);
559
560 /* drop dentry if it's there and dput() didn't kill it yet */
561 if (sd->s_dentry && sd->s_dentry->d_inode) {
562 dentry = dget_locked(sd->s_dentry);
563 spin_lock(&dentry->d_lock);
564 __d_drop(dentry);
565 spin_unlock(&dentry->d_lock);
566 }
141 567
142 sd = __sysfs_make_dirent(dentry, element, mode, type); 568 spin_unlock(&dcache_lock);
143 __sysfs_list_dirent(parent_sd, sd); 569 spin_unlock(&sysfs_assoc_lock);
144 570
145 return sd ? 0 : -ENOMEM; 571 /* dentries for shadowed inodes are pinned, unpin */
572 if (dentry && sysfs_is_shadowed_inode(dentry->d_inode))
573 dput(dentry);
574 dput(dentry);
575
576 /* adjust nlink and update timestamp */
577 inode = ilookup(sysfs_sb, sd->s_ino);
578 if (inode) {
579 mutex_lock(&inode->i_mutex);
580
581 inode->i_ctime = CURRENT_TIME;
582 drop_nlink(inode);
583 if (sysfs_type(sd) == SYSFS_DIR)
584 drop_nlink(inode);
585
586 mutex_unlock(&inode->i_mutex);
587 iput(inode);
588 }
146} 589}
147 590
148static int init_dir(struct inode * inode) 591/**
592 * sysfs_addrm_finish - finish up sysfs_dirent add/remove
593 * @acxt: addrm context to finish up
594 *
595 * Finish up sysfs_dirent add/remove. Resources acquired by
596 * sysfs_addrm_start() are released and removed sysfs_dirents are
597 * cleaned up. Timestamps on the parent inode are updated.
598 *
599 * LOCKING:
600 * All mutexes acquired by sysfs_addrm_start() are released.
601 *
602 * RETURNS:
603 * Number of added/removed sysfs_dirents since sysfs_addrm_start().
604 */
605int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
149{ 606{
150 inode->i_op = &sysfs_dir_inode_operations; 607 /* release resources acquired by sysfs_addrm_start() */
151 inode->i_fop = &sysfs_dir_operations; 608 mutex_unlock(&sysfs_mutex);
609 if (acxt->parent_inode) {
610 struct inode *inode = acxt->parent_inode;
152 611
153 /* directory inodes start off with i_nlink == 2 (for "." entry) */ 612 /* if added/removed, update timestamps on the parent */
154 inc_nlink(inode); 613 if (acxt->cnt)
155 return 0; 614 inode->i_ctime = inode->i_mtime = CURRENT_TIME;
615
616 mutex_unlock(&inode->i_mutex);
617 iput(inode);
618 }
619
620 /* kill removed sysfs_dirents */
621 while (acxt->removed) {
622 struct sysfs_dirent *sd = acxt->removed;
623
624 acxt->removed = sd->s_sibling;
625 sd->s_sibling = NULL;
626
627 sysfs_drop_dentry(sd);
628 sysfs_deactivate(sd);
629 sysfs_put(sd);
630 }
631
632 return acxt->cnt;
156} 633}
157 634
158static int init_file(struct inode * inode) 635/**
636 * sysfs_find_dirent - find sysfs_dirent with the given name
637 * @parent_sd: sysfs_dirent to search under
638 * @name: name to look for
639 *
640 * Look for sysfs_dirent with name @name under @parent_sd.
641 *
642 * LOCKING:
643 * mutex_lock(sysfs_mutex)
644 *
645 * RETURNS:
646 * Pointer to sysfs_dirent if found, NULL if not.
647 */
648struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
649 const unsigned char *name)
159{ 650{
160 inode->i_size = PAGE_SIZE; 651 struct sysfs_dirent *sd;
161 inode->i_fop = &sysfs_file_operations; 652
162 return 0; 653 for (sd = parent_sd->s_children; sd; sd = sd->s_sibling)
654 if (sysfs_type(sd) && !strcmp(sd->s_name, name))
655 return sd;
656 return NULL;
163} 657}
164 658
165static int init_symlink(struct inode * inode) 659/**
660 * sysfs_get_dirent - find and get sysfs_dirent with the given name
661 * @parent_sd: sysfs_dirent to search under
662 * @name: name to look for
663 *
664 * Look for sysfs_dirent with name @name under @parent_sd and get
665 * it if found.
666 *
667 * LOCKING:
668 * Kernel thread context (may sleep). Grabs sysfs_mutex.
669 *
670 * RETURNS:
671 * Pointer to sysfs_dirent if found, NULL if not.
672 */
673struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
674 const unsigned char *name)
166{ 675{
167 inode->i_op = &sysfs_symlink_inode_operations; 676 struct sysfs_dirent *sd;
168 return 0; 677
678 mutex_lock(&sysfs_mutex);
679 sd = sysfs_find_dirent(parent_sd, name);
680 sysfs_get(sd);
681 mutex_unlock(&sysfs_mutex);
682
683 return sd;
169} 684}
170 685
171static int create_dir(struct kobject * k, struct dentry * p, 686static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
172 const char * n, struct dentry ** d) 687 const char *name, struct sysfs_dirent **p_sd)
173{ 688{
174 int error;
175 umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; 689 umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
690 struct sysfs_addrm_cxt acxt;
691 struct sysfs_dirent *sd;
176 692
177 mutex_lock(&p->d_inode->i_mutex); 693 /* allocate */
178 *d = lookup_one_len(n, p, strlen(n)); 694 sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
179 if (!IS_ERR(*d)) { 695 if (!sd)
180 if (sysfs_dirent_exist(p->d_fsdata, n)) 696 return -ENOMEM;
181 error = -EEXIST; 697 sd->s_elem.dir.kobj = kobj;
182 else
183 error = sysfs_make_dirent(p->d_fsdata, *d, k, mode,
184 SYSFS_DIR);
185 if (!error) {
186 error = sysfs_create(*d, mode, init_dir);
187 if (!error) {
188 inc_nlink(p->d_inode);
189 (*d)->d_op = &sysfs_dentry_ops;
190 d_rehash(*d);
191 }
192 }
193 if (error && (error != -EEXIST)) {
194 struct sysfs_dirent *sd = (*d)->d_fsdata;
195 if (sd) {
196 list_del_init(&sd->s_sibling);
197 sysfs_put(sd);
198 }
199 d_drop(*d);
200 }
201 dput(*d);
202 } else
203 error = PTR_ERR(*d);
204 mutex_unlock(&p->d_inode->i_mutex);
205 return error;
206}
207 698
699 /* link in */
700 sysfs_addrm_start(&acxt, parent_sd);
701 if (!sysfs_find_dirent(parent_sd, name)) {
702 sysfs_add_one(&acxt, sd);
703 sysfs_link_sibling(sd);
704 }
705 if (sysfs_addrm_finish(&acxt)) {
706 *p_sd = sd;
707 return 0;
708 }
208 709
209int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d) 710 sysfs_put(sd);
711 return -EEXIST;
712}
713
714int sysfs_create_subdir(struct kobject *kobj, const char *name,
715 struct sysfs_dirent **p_sd)
210{ 716{
211 return create_dir(k,k->dentry,n,d); 717 return create_dir(kobj, kobj->sd, name, p_sd);
212} 718}
213 719
214/** 720/**
215 * sysfs_create_dir - create a directory for an object. 721 * sysfs_create_dir - create a directory for an object.
216 * @kobj: object we're creating directory for. 722 * @kobj: object we're creating directory for.
217 * @shadow_parent: parent parent object. 723 * @shadow_parent: parent object.
218 */ 724 */
219 725int sysfs_create_dir(struct kobject *kobj,
220int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent) 726 struct sysfs_dirent *shadow_parent_sd)
221{ 727{
222 struct dentry * dentry = NULL; 728 struct sysfs_dirent *parent_sd, *sd;
223 struct dentry * parent;
224 int error = 0; 729 int error = 0;
225 730
226 BUG_ON(!kobj); 731 BUG_ON(!kobj);
227 732
228 if (shadow_parent) 733 if (shadow_parent_sd)
229 parent = shadow_parent; 734 parent_sd = shadow_parent_sd;
230 else if (kobj->parent) 735 else if (kobj->parent)
231 parent = kobj->parent->dentry; 736 parent_sd = kobj->parent->sd;
232 else if (sysfs_mount && sysfs_mount->mnt_sb) 737 else if (sysfs_mount && sysfs_mount->mnt_sb)
233 parent = sysfs_mount->mnt_sb->s_root; 738 parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
234 else 739 else
235 return -EFAULT; 740 return -EFAULT;
236 741
237 error = create_dir(kobj,parent,kobject_name(kobj),&dentry); 742 error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd);
238 if (!error) 743 if (!error)
239 kobj->dentry = dentry; 744 kobj->sd = sd;
240 return error; 745 return error;
241} 746}
242 747
243/* attaches attribute's sysfs_dirent to the dentry corresponding to the 748static int sysfs_count_nlink(struct sysfs_dirent *sd)
244 * attribute file
245 */
246static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
247{ 749{
248 struct attribute * attr = NULL; 750 struct sysfs_dirent *child;
249 struct bin_attribute * bin_attr = NULL; 751 int nr = 0;
250 int (* init) (struct inode *) = NULL;
251 int error = 0;
252
253 if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
254 bin_attr = sd->s_element;
255 attr = &bin_attr->attr;
256 } else {
257 attr = sd->s_element;
258 init = init_file;
259 }
260 752
261 dentry->d_fsdata = sysfs_get(sd); 753 for (child = sd->s_children; child; child = child->s_sibling)
262 /* protect sd->s_dentry against sysfs_d_iput */ 754 if (sysfs_type(child) == SYSFS_DIR)
263 spin_lock(&sysfs_lock); 755 nr++;
264 sd->s_dentry = dentry; 756 return nr + 2;
265 spin_unlock(&sysfs_lock);
266 error = sysfs_create(dentry, (attr->mode & S_IALLUGO) | S_IFREG, init);
267 if (error) {
268 sysfs_put(sd);
269 return error;
270 }
271
272 if (bin_attr) {
273 dentry->d_inode->i_size = bin_attr->size;
274 dentry->d_inode->i_fop = &bin_fops;
275 }
276 dentry->d_op = &sysfs_dentry_ops;
277 d_rehash(dentry);
278
279 return 0;
280}
281
282static int sysfs_attach_link(struct sysfs_dirent * sd, struct dentry * dentry)
283{
284 int err = 0;
285
286 dentry->d_fsdata = sysfs_get(sd);
287 /* protect sd->s_dentry against sysfs_d_iput */
288 spin_lock(&sysfs_lock);
289 sd->s_dentry = dentry;
290 spin_unlock(&sysfs_lock);
291 err = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
292 if (!err) {
293 dentry->d_op = &sysfs_dentry_ops;
294 d_rehash(dentry);
295 } else
296 sysfs_put(sd);
297
298 return err;
299} 757}
300 758
301static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, 759static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
@@ -303,24 +761,60 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
303{ 761{
304 struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata; 762 struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
305 struct sysfs_dirent * sd; 763 struct sysfs_dirent * sd;
306 int err = 0; 764 struct bin_attribute *bin_attr;
765 struct inode *inode;
766 int found = 0;
307 767
308 list_for_each_entry(sd, &parent_sd->s_children, s_sibling) { 768 for (sd = parent_sd->s_children; sd; sd = sd->s_sibling) {
309 if (sd->s_type & SYSFS_NOT_PINNED) { 769 if (sysfs_type(sd) &&
310 const unsigned char * name = sysfs_get_name(sd); 770 !strcmp(sd->s_name, dentry->d_name.name)) {
771 found = 1;
772 break;
773 }
774 }
311 775
312 if (strcmp(name, dentry->d_name.name)) 776 /* no such entry */
313 continue; 777 if (!found)
778 return NULL;
314 779
315 if (sd->s_type & SYSFS_KOBJ_LINK) 780 /* attach dentry and inode */
316 err = sysfs_attach_link(sd, dentry); 781 inode = sysfs_get_inode(sd);
317 else 782 if (!inode)
318 err = sysfs_attach_attr(sd, dentry); 783 return ERR_PTR(-ENOMEM);
784
785 mutex_lock(&sysfs_mutex);
786
787 if (inode->i_state & I_NEW) {
788 /* initialize inode according to type */
789 switch (sysfs_type(sd)) {
790 case SYSFS_DIR:
791 inode->i_op = &sysfs_dir_inode_operations;
792 inode->i_fop = &sysfs_dir_operations;
793 inode->i_nlink = sysfs_count_nlink(sd);
794 break;
795 case SYSFS_KOBJ_ATTR:
796 inode->i_size = PAGE_SIZE;
797 inode->i_fop = &sysfs_file_operations;
798 break;
799 case SYSFS_KOBJ_BIN_ATTR:
800 bin_attr = sd->s_elem.bin_attr.bin_attr;
801 inode->i_size = bin_attr->size;
802 inode->i_fop = &bin_fops;
319 break; 803 break;
804 case SYSFS_KOBJ_LINK:
805 inode->i_op = &sysfs_symlink_inode_operations;
806 break;
807 default:
808 BUG();
320 } 809 }
321 } 810 }
322 811
323 return ERR_PTR(err); 812 sysfs_instantiate(dentry, inode);
813 sysfs_attach_dentry(sd, dentry);
814
815 mutex_unlock(&sysfs_mutex);
816
817 return NULL;
324} 818}
325 819
326const struct inode_operations sysfs_dir_inode_operations = { 820const struct inode_operations sysfs_dir_inode_operations = {
@@ -328,58 +822,46 @@ const struct inode_operations sysfs_dir_inode_operations = {
328 .setattr = sysfs_setattr, 822 .setattr = sysfs_setattr,
329}; 823};
330 824
331static void remove_dir(struct dentry * d) 825static void remove_dir(struct sysfs_dirent *sd)
332{ 826{
333 struct dentry * parent = dget(d->d_parent); 827 struct sysfs_addrm_cxt acxt;
334 struct sysfs_dirent * sd;
335
336 mutex_lock(&parent->d_inode->i_mutex);
337 d_delete(d);
338 sd = d->d_fsdata;
339 list_del_init(&sd->s_sibling);
340 sysfs_put(sd);
341 if (d->d_inode)
342 simple_rmdir(parent->d_inode,d);
343
344 pr_debug(" o %s removing done (%d)\n",d->d_name.name,
345 atomic_read(&d->d_count));
346 828
347 mutex_unlock(&parent->d_inode->i_mutex); 829 sysfs_addrm_start(&acxt, sd->s_parent);
348 dput(parent); 830 sysfs_unlink_sibling(sd);
831 sysfs_remove_one(&acxt, sd);
832 sysfs_addrm_finish(&acxt);
349} 833}
350 834
351void sysfs_remove_subdir(struct dentry * d) 835void sysfs_remove_subdir(struct sysfs_dirent *sd)
352{ 836{
353 remove_dir(d); 837 remove_dir(sd);
354} 838}
355 839
356 840
357static void __sysfs_remove_dir(struct dentry *dentry) 841static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd)
358{ 842{
359 struct sysfs_dirent * parent_sd; 843 struct sysfs_addrm_cxt acxt;
360 struct sysfs_dirent * sd, * tmp; 844 struct sysfs_dirent **pos;
361 845
362 dget(dentry); 846 if (!dir_sd)
363 if (!dentry)
364 return; 847 return;
365 848
366 pr_debug("sysfs %s: removing dir\n",dentry->d_name.name); 849 pr_debug("sysfs %s: removing dir\n", dir_sd->s_name);
367 mutex_lock(&dentry->d_inode->i_mutex); 850 sysfs_addrm_start(&acxt, dir_sd);
368 parent_sd = dentry->d_fsdata; 851 pos = &dir_sd->s_children;
369 list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) { 852 while (*pos) {
370 if (!sd->s_element || !(sd->s_type & SYSFS_NOT_PINNED)) 853 struct sysfs_dirent *sd = *pos;
371 continue; 854
372 list_del_init(&sd->s_sibling); 855 if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR) {
373 sysfs_drop_dentry(sd, dentry); 856 *pos = sd->s_sibling;
374 sysfs_put(sd); 857 sd->s_sibling = NULL;
858 sysfs_remove_one(&acxt, sd);
859 } else
860 pos = &(*pos)->s_sibling;
375 } 861 }
376 mutex_unlock(&dentry->d_inode->i_mutex); 862 sysfs_addrm_finish(&acxt);
377 863
378 remove_dir(dentry); 864 remove_dir(dir_sd);
379 /**
380 * Drop reference from dget() on entrance.
381 */
382 dput(dentry);
383} 865}
384 866
385/** 867/**
@@ -393,102 +875,166 @@ static void __sysfs_remove_dir(struct dentry *dentry)
393 875
394void sysfs_remove_dir(struct kobject * kobj) 876void sysfs_remove_dir(struct kobject * kobj)
395{ 877{
396 __sysfs_remove_dir(kobj->dentry); 878 struct sysfs_dirent *sd = kobj->sd;
397 kobj->dentry = NULL; 879
880 spin_lock(&sysfs_assoc_lock);
881 kobj->sd = NULL;
882 spin_unlock(&sysfs_assoc_lock);
883
884 __sysfs_remove_dir(sd);
398} 885}
399 886
400int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, 887int sysfs_rename_dir(struct kobject *kobj, struct sysfs_dirent *new_parent_sd,
401 const char *new_name) 888 const char *new_name)
402{ 889{
403 int error = 0; 890 struct sysfs_dirent *sd = kobj->sd;
404 struct dentry * new_dentry; 891 struct dentry *new_parent = NULL;
892 struct dentry *old_dentry = NULL, *new_dentry = NULL;
893 const char *dup_name = NULL;
894 int error;
405 895
406 if (!new_parent) 896 /* get dentries */
407 return -EFAULT; 897 old_dentry = sysfs_get_dentry(sd);
898 if (IS_ERR(old_dentry)) {
899 error = PTR_ERR(old_dentry);
900 goto out_dput;
901 }
408 902
409 down_write(&sysfs_rename_sem); 903 new_parent = sysfs_get_dentry(new_parent_sd);
904 if (IS_ERR(new_parent)) {
905 error = PTR_ERR(new_parent);
906 goto out_dput;
907 }
908
909 /* lock new_parent and get dentry for new name */
410 mutex_lock(&new_parent->d_inode->i_mutex); 910 mutex_lock(&new_parent->d_inode->i_mutex);
411 911
412 new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name)); 912 new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name));
413 if (!IS_ERR(new_dentry)) { 913 if (IS_ERR(new_dentry)) {
414 /* By allowing two different directories with the 914 error = PTR_ERR(new_dentry);
415 * same d_parent we allow this routine to move 915 goto out_unlock;
416 * between different shadows of the same directory
417 */
418 if (kobj->dentry->d_parent->d_inode != new_parent->d_inode)
419 return -EINVAL;
420 else if (new_dentry->d_parent->d_inode != new_parent->d_inode)
421 error = -EINVAL;
422 else if (new_dentry == kobj->dentry)
423 error = -EINVAL;
424 else if (!new_dentry->d_inode) {
425 error = kobject_set_name(kobj, "%s", new_name);
426 if (!error) {
427 struct sysfs_dirent *sd, *parent_sd;
428
429 d_add(new_dentry, NULL);
430 d_move(kobj->dentry, new_dentry);
431
432 sd = kobj->dentry->d_fsdata;
433 parent_sd = new_parent->d_fsdata;
434
435 list_del_init(&sd->s_sibling);
436 list_add(&sd->s_sibling, &parent_sd->s_children);
437 }
438 else
439 d_drop(new_dentry);
440 } else
441 error = -EEXIST;
442 dput(new_dentry);
443 } 916 }
444 mutex_unlock(&new_parent->d_inode->i_mutex);
445 up_write(&sysfs_rename_sem);
446 917
918 /* By allowing two different directories with the same
919 * d_parent we allow this routine to move between different
920 * shadows of the same directory
921 */
922 error = -EINVAL;
923 if (old_dentry->d_parent->d_inode != new_parent->d_inode ||
924 new_dentry->d_parent->d_inode != new_parent->d_inode ||
925 old_dentry == new_dentry)
926 goto out_unlock;
927
928 error = -EEXIST;
929 if (new_dentry->d_inode)
930 goto out_unlock;
931
932 /* rename kobject and sysfs_dirent */
933 error = -ENOMEM;
934 new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
935 if (!new_name)
936 goto out_drop;
937
938 error = kobject_set_name(kobj, "%s", new_name);
939 if (error)
940 goto out_drop;
941
942 dup_name = sd->s_name;
943 sd->s_name = new_name;
944
945 /* move under the new parent */
946 d_add(new_dentry, NULL);
947 d_move(sd->s_dentry, new_dentry);
948
949 mutex_lock(&sysfs_mutex);
950
951 sysfs_unlink_sibling(sd);
952 sysfs_get(new_parent_sd);
953 sysfs_put(sd->s_parent);
954 sd->s_parent = new_parent_sd;
955 sysfs_link_sibling(sd);
956
957 mutex_unlock(&sysfs_mutex);
958
959 error = 0;
960 goto out_unlock;
961
962 out_drop:
963 d_drop(new_dentry);
964 out_unlock:
965 mutex_unlock(&new_parent->d_inode->i_mutex);
966 out_dput:
967 kfree(dup_name);
968 dput(new_parent);
969 dput(old_dentry);
970 dput(new_dentry);
447 return error; 971 return error;
448} 972}
449 973
450int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent) 974int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj)
451{ 975{
452 struct dentry *old_parent_dentry, *new_parent_dentry, *new_dentry; 976 struct sysfs_dirent *sd = kobj->sd;
453 struct sysfs_dirent *new_parent_sd, *sd; 977 struct sysfs_dirent *new_parent_sd;
978 struct dentry *old_parent, *new_parent = NULL;
979 struct dentry *old_dentry = NULL, *new_dentry = NULL;
454 int error; 980 int error;
455 981
456 old_parent_dentry = kobj->parent ? 982 BUG_ON(!sd->s_parent);
457 kobj->parent->dentry : sysfs_mount->mnt_sb->s_root; 983 new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root;
458 new_parent_dentry = new_parent ? 984
459 new_parent->dentry : sysfs_mount->mnt_sb->s_root; 985 /* get dentries */
986 old_dentry = sysfs_get_dentry(sd);
987 if (IS_ERR(old_dentry)) {
988 error = PTR_ERR(old_dentry);
989 goto out_dput;
990 }
991 old_parent = sd->s_parent->s_dentry;
992
993 new_parent = sysfs_get_dentry(new_parent_sd);
994 if (IS_ERR(new_parent)) {
995 error = PTR_ERR(new_parent);
996 goto out_dput;
997 }
460 998
461 if (old_parent_dentry->d_inode == new_parent_dentry->d_inode) 999 if (old_parent->d_inode == new_parent->d_inode) {
462 return 0; /* nothing to move */ 1000 error = 0;
1001 goto out_dput; /* nothing to move */
1002 }
463again: 1003again:
464 mutex_lock(&old_parent_dentry->d_inode->i_mutex); 1004 mutex_lock(&old_parent->d_inode->i_mutex);
465 if (!mutex_trylock(&new_parent_dentry->d_inode->i_mutex)) { 1005 if (!mutex_trylock(&new_parent->d_inode->i_mutex)) {
466 mutex_unlock(&old_parent_dentry->d_inode->i_mutex); 1006 mutex_unlock(&old_parent->d_inode->i_mutex);
467 goto again; 1007 goto again;
468 } 1008 }
469 1009
470 new_parent_sd = new_parent_dentry->d_fsdata; 1010 new_dentry = lookup_one_len(kobj->name, new_parent, strlen(kobj->name));
471 sd = kobj->dentry->d_fsdata;
472
473 new_dentry = lookup_one_len(kobj->name, new_parent_dentry,
474 strlen(kobj->name));
475 if (IS_ERR(new_dentry)) { 1011 if (IS_ERR(new_dentry)) {
476 error = PTR_ERR(new_dentry); 1012 error = PTR_ERR(new_dentry);
477 goto out; 1013 goto out_unlock;
478 } else 1014 } else
479 error = 0; 1015 error = 0;
480 d_add(new_dentry, NULL); 1016 d_add(new_dentry, NULL);
481 d_move(kobj->dentry, new_dentry); 1017 d_move(sd->s_dentry, new_dentry);
482 dput(new_dentry); 1018 dput(new_dentry);
483 1019
484 /* Remove from old parent's list and insert into new parent's list. */ 1020 /* Remove from old parent's list and insert into new parent's list. */
485 list_del_init(&sd->s_sibling); 1021 mutex_lock(&sysfs_mutex);
486 list_add(&sd->s_sibling, &new_parent_sd->s_children); 1022
1023 sysfs_unlink_sibling(sd);
1024 sysfs_get(new_parent_sd);
1025 sysfs_put(sd->s_parent);
1026 sd->s_parent = new_parent_sd;
1027 sysfs_link_sibling(sd);
487 1028
488out: 1029 mutex_unlock(&sysfs_mutex);
489 mutex_unlock(&new_parent_dentry->d_inode->i_mutex);
490 mutex_unlock(&old_parent_dentry->d_inode->i_mutex);
491 1030
1031 out_unlock:
1032 mutex_unlock(&new_parent->d_inode->i_mutex);
1033 mutex_unlock(&old_parent->d_inode->i_mutex);
1034 out_dput:
1035 dput(new_parent);
1036 dput(old_dentry);
1037 dput(new_dentry);
492 return error; 1038 return error;
493} 1039}
494 1040
@@ -496,23 +1042,27 @@ static int sysfs_dir_open(struct inode *inode, struct file *file)
496{ 1042{
497 struct dentry * dentry = file->f_path.dentry; 1043 struct dentry * dentry = file->f_path.dentry;
498 struct sysfs_dirent * parent_sd = dentry->d_fsdata; 1044 struct sysfs_dirent * parent_sd = dentry->d_fsdata;
1045 struct sysfs_dirent * sd;
499 1046
500 mutex_lock(&dentry->d_inode->i_mutex); 1047 sd = sysfs_new_dirent("_DIR_", 0, 0);
501 file->private_data = sysfs_new_dirent(parent_sd, NULL); 1048 if (sd) {
502 mutex_unlock(&dentry->d_inode->i_mutex); 1049 mutex_lock(&sysfs_mutex);
503 1050 sd->s_parent = sysfs_get(parent_sd);
504 return file->private_data ? 0 : -ENOMEM; 1051 sysfs_link_sibling(sd);
1052 mutex_unlock(&sysfs_mutex);
1053 }
505 1054
1055 file->private_data = sd;
1056 return sd ? 0 : -ENOMEM;
506} 1057}
507 1058
508static int sysfs_dir_close(struct inode *inode, struct file *file) 1059static int sysfs_dir_close(struct inode *inode, struct file *file)
509{ 1060{
510 struct dentry * dentry = file->f_path.dentry;
511 struct sysfs_dirent * cursor = file->private_data; 1061 struct sysfs_dirent * cursor = file->private_data;
512 1062
513 mutex_lock(&dentry->d_inode->i_mutex); 1063 mutex_lock(&sysfs_mutex);
514 list_del_init(&cursor->s_sibling); 1064 sysfs_unlink_sibling(cursor);
515 mutex_unlock(&dentry->d_inode->i_mutex); 1065 mutex_unlock(&sysfs_mutex);
516 1066
517 release_sysfs_dirent(cursor); 1067 release_sysfs_dirent(cursor);
518 1068
@@ -530,7 +1080,7 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
530 struct dentry *dentry = filp->f_path.dentry; 1080 struct dentry *dentry = filp->f_path.dentry;
531 struct sysfs_dirent * parent_sd = dentry->d_fsdata; 1081 struct sysfs_dirent * parent_sd = dentry->d_fsdata;
532 struct sysfs_dirent *cursor = filp->private_data; 1082 struct sysfs_dirent *cursor = filp->private_data;
533 struct list_head *p, *q = &cursor->s_sibling; 1083 struct sysfs_dirent **pos;
534 ino_t ino; 1084 ino_t ino;
535 int i = filp->f_pos; 1085 int i = filp->f_pos;
536 1086
@@ -543,38 +1093,52 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
543 i++; 1093 i++;
544 /* fallthrough */ 1094 /* fallthrough */
545 case 1: 1095 case 1:
546 ino = parent_ino(dentry); 1096 if (parent_sd->s_parent)
1097 ino = parent_sd->s_parent->s_ino;
1098 else
1099 ino = parent_sd->s_ino;
547 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1100 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
548 break; 1101 break;
549 filp->f_pos++; 1102 filp->f_pos++;
550 i++; 1103 i++;
551 /* fallthrough */ 1104 /* fallthrough */
552 default: 1105 default:
1106 mutex_lock(&sysfs_mutex);
1107
1108 pos = &parent_sd->s_children;
1109 while (*pos != cursor)
1110 pos = &(*pos)->s_sibling;
1111
1112 /* unlink cursor */
1113 *pos = cursor->s_sibling;
1114
553 if (filp->f_pos == 2) 1115 if (filp->f_pos == 2)
554 list_move(q, &parent_sd->s_children); 1116 pos = &parent_sd->s_children;
555 1117
556 for (p=q->next; p!= &parent_sd->s_children; p=p->next) { 1118 for ( ; *pos; pos = &(*pos)->s_sibling) {
557 struct sysfs_dirent *next; 1119 struct sysfs_dirent *next = *pos;
558 const char * name; 1120 const char * name;
559 int len; 1121 int len;
560 1122
561 next = list_entry(p, struct sysfs_dirent, 1123 if (!sysfs_type(next))
562 s_sibling);
563 if (!next->s_element)
564 continue; 1124 continue;
565 1125
566 name = sysfs_get_name(next); 1126 name = next->s_name;
567 len = strlen(name); 1127 len = strlen(name);
568 ino = next->s_ino; 1128 ino = next->s_ino;
569 1129
570 if (filldir(dirent, name, len, filp->f_pos, ino, 1130 if (filldir(dirent, name, len, filp->f_pos, ino,
571 dt_type(next)) < 0) 1131 dt_type(next)) < 0)
572 return 0; 1132 break;
573 1133
574 list_move(q, p);
575 p = q;
576 filp->f_pos++; 1134 filp->f_pos++;
577 } 1135 }
1136
1137 /* put cursor back in */
1138 cursor->s_sibling = *pos;
1139 *pos = cursor;
1140
1141 mutex_unlock(&sysfs_mutex);
578 } 1142 }
579 return 0; 1143 return 0;
580} 1144}
@@ -583,7 +1147,6 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
583{ 1147{
584 struct dentry * dentry = file->f_path.dentry; 1148 struct dentry * dentry = file->f_path.dentry;
585 1149
586 mutex_lock(&dentry->d_inode->i_mutex);
587 switch (origin) { 1150 switch (origin) {
588 case 1: 1151 case 1:
589 offset += file->f_pos; 1152 offset += file->f_pos;
@@ -591,31 +1154,35 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
591 if (offset >= 0) 1154 if (offset >= 0)
592 break; 1155 break;
593 default: 1156 default:
594 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
595 return -EINVAL; 1157 return -EINVAL;
596 } 1158 }
597 if (offset != file->f_pos) { 1159 if (offset != file->f_pos) {
1160 mutex_lock(&sysfs_mutex);
1161
598 file->f_pos = offset; 1162 file->f_pos = offset;
599 if (file->f_pos >= 2) { 1163 if (file->f_pos >= 2) {
600 struct sysfs_dirent *sd = dentry->d_fsdata; 1164 struct sysfs_dirent *sd = dentry->d_fsdata;
601 struct sysfs_dirent *cursor = file->private_data; 1165 struct sysfs_dirent *cursor = file->private_data;
602 struct list_head *p; 1166 struct sysfs_dirent **pos;
603 loff_t n = file->f_pos - 2; 1167 loff_t n = file->f_pos - 2;
604 1168
605 list_del(&cursor->s_sibling); 1169 sysfs_unlink_sibling(cursor);
606 p = sd->s_children.next; 1170
607 while (n && p != &sd->s_children) { 1171 pos = &sd->s_children;
608 struct sysfs_dirent *next; 1172 while (n && *pos) {
609 next = list_entry(p, struct sysfs_dirent, 1173 struct sysfs_dirent *next = *pos;
610 s_sibling); 1174 if (sysfs_type(next))
611 if (next->s_element)
612 n--; 1175 n--;
613 p = p->next; 1176 pos = &(*pos)->s_sibling;
614 } 1177 }
615 list_add_tail(&cursor->s_sibling, p); 1178
1179 cursor->s_sibling = *pos;
1180 *pos = cursor;
616 } 1181 }
1182
1183 mutex_unlock(&sysfs_mutex);
617 } 1184 }
618 mutex_unlock(&dentry->d_inode->i_mutex); 1185
619 return offset; 1186 return offset;
620} 1187}
621 1188
@@ -628,12 +1195,20 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
628int sysfs_make_shadowed_dir(struct kobject *kobj, 1195int sysfs_make_shadowed_dir(struct kobject *kobj,
629 void * (*follow_link)(struct dentry *, struct nameidata *)) 1196 void * (*follow_link)(struct dentry *, struct nameidata *))
630{ 1197{
1198 struct dentry *dentry;
631 struct inode *inode; 1199 struct inode *inode;
632 struct inode_operations *i_op; 1200 struct inode_operations *i_op;
633 1201
634 inode = kobj->dentry->d_inode; 1202 /* get dentry for @kobj->sd, dentry of a shadowed dir is pinned */
635 if (inode->i_op != &sysfs_dir_inode_operations) 1203 dentry = sysfs_get_dentry(kobj->sd);
1204 if (IS_ERR(dentry))
1205 return PTR_ERR(dentry);
1206
1207 inode = dentry->d_inode;
1208 if (inode->i_op != &sysfs_dir_inode_operations) {
1209 dput(dentry);
636 return -EINVAL; 1210 return -EINVAL;
1211 }
637 1212
638 i_op = kmalloc(sizeof(*i_op), GFP_KERNEL); 1213 i_op = kmalloc(sizeof(*i_op), GFP_KERNEL);
639 if (!i_op) 1214 if (!i_op)
@@ -658,54 +1233,72 @@ int sysfs_make_shadowed_dir(struct kobject *kobj,
658 * directory. 1233 * directory.
659 */ 1234 */
660 1235
661struct dentry *sysfs_create_shadow_dir(struct kobject *kobj) 1236struct sysfs_dirent *sysfs_create_shadow_dir(struct kobject *kobj)
662{ 1237{
663 struct sysfs_dirent *sd; 1238 struct sysfs_dirent *parent_sd = kobj->sd->s_parent;
664 struct dentry *parent, *dir, *shadow; 1239 struct dentry *dir, *parent, *shadow;
665 struct inode *inode; 1240 struct inode *inode;
1241 struct sysfs_dirent *sd;
1242 struct sysfs_addrm_cxt acxt;
666 1243
667 dir = kobj->dentry; 1244 dir = sysfs_get_dentry(kobj->sd);
668 inode = dir->d_inode; 1245 if (IS_ERR(dir)) {
1246 sd = (void *)dir;
1247 goto out;
1248 }
669 parent = dir->d_parent; 1249 parent = dir->d_parent;
670 shadow = ERR_PTR(-EINVAL); 1250
1251 inode = dir->d_inode;
1252 sd = ERR_PTR(-EINVAL);
671 if (!sysfs_is_shadowed_inode(inode)) 1253 if (!sysfs_is_shadowed_inode(inode))
672 goto out; 1254 goto out_dput;
673 1255
674 shadow = d_alloc(parent, &dir->d_name); 1256 shadow = d_alloc(parent, &dir->d_name);
675 if (!shadow) 1257 if (!shadow)
676 goto nomem; 1258 goto nomem;
677 1259
678 sd = __sysfs_make_dirent(shadow, kobj, inode->i_mode, SYSFS_DIR); 1260 sd = sysfs_new_dirent("_SHADOW_", inode->i_mode, SYSFS_DIR);
679 if (!sd) 1261 if (!sd)
680 goto nomem; 1262 goto nomem;
1263 sd->s_elem.dir.kobj = kobj;
681 1264
1265 sysfs_addrm_start(&acxt, parent_sd);
1266
1267 /* add but don't link into children list */
1268 sysfs_add_one(&acxt, sd);
1269
1270 /* attach and instantiate dentry */
1271 sysfs_attach_dentry(sd, shadow);
682 d_instantiate(shadow, igrab(inode)); 1272 d_instantiate(shadow, igrab(inode));
683 inc_nlink(inode); 1273 inc_nlink(inode); /* tj: synchronization? */
684 inc_nlink(parent->d_inode); 1274
685 shadow->d_op = &sysfs_dentry_ops; 1275 sysfs_addrm_finish(&acxt);
686 1276
687 dget(shadow); /* Extra count - pin the dentry in core */ 1277 dget(shadow); /* Extra count - pin the dentry in core */
688 1278
689out: 1279 goto out_dput;
690 return shadow; 1280
691nomem: 1281 nomem:
692 dput(shadow); 1282 dput(shadow);
693 shadow = ERR_PTR(-ENOMEM); 1283 sd = ERR_PTR(-ENOMEM);
694 goto out; 1284 out_dput:
1285 dput(dir);
1286 out:
1287 return sd;
695} 1288}
696 1289
697/** 1290/**
698 * sysfs_remove_shadow_dir - remove an object's directory. 1291 * sysfs_remove_shadow_dir - remove an object's directory.
699 * @shadow: dentry of shadow directory 1292 * @shadow_sd: sysfs_dirent of shadow directory
700 * 1293 *
701 * The only thing special about this is that we remove any files in 1294 * The only thing special about this is that we remove any files in
702 * the directory before we remove the directory, and we've inlined 1295 * the directory before we remove the directory, and we've inlined
703 * what used to be sysfs_rmdir() below, instead of calling separately. 1296 * what used to be sysfs_rmdir() below, instead of calling separately.
704 */ 1297 */
705 1298
706void sysfs_remove_shadow_dir(struct dentry *shadow) 1299void sysfs_remove_shadow_dir(struct sysfs_dirent *shadow_sd)
707{ 1300{
708 __sysfs_remove_dir(shadow); 1301 __sysfs_remove_dir(shadow_sd);
709} 1302}
710 1303
711const struct file_operations sysfs_dir_operations = { 1304const struct file_operations sysfs_dir_operations = {
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index b502c7197ec0..cc497994b2a8 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -50,29 +50,15 @@ static struct sysfs_ops subsys_sysfs_ops = {
50 .store = subsys_attr_store, 50 .store = subsys_attr_store,
51}; 51};
52 52
53/** 53struct sysfs_buffer {
54 * add_to_collection - add buffer to a collection 54 size_t count;
55 * @buffer: buffer to be added 55 loff_t pos;
56 * @node: inode of set to add to 56 char * page;
57 */ 57 struct sysfs_ops * ops;
58 58 struct semaphore sem;
59static inline void 59 int needs_read_fill;
60add_to_collection(struct sysfs_buffer *buffer, struct inode *node) 60 int event;
61{ 61};
62 struct sysfs_buffer_collection *set = node->i_private;
63
64 mutex_lock(&node->i_mutex);
65 list_add(&buffer->associates, &set->associates);
66 mutex_unlock(&node->i_mutex);
67}
68
69static inline void
70remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
71{
72 mutex_lock(&node->i_mutex);
73 list_del(&buffer->associates);
74 mutex_unlock(&node->i_mutex);
75}
76 62
77/** 63/**
78 * fill_read_buffer - allocate and fill buffer from object. 64 * fill_read_buffer - allocate and fill buffer from object.
@@ -87,9 +73,8 @@ remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
87 */ 73 */
88static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer) 74static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
89{ 75{
90 struct sysfs_dirent * sd = dentry->d_fsdata; 76 struct sysfs_dirent *attr_sd = dentry->d_fsdata;
91 struct attribute * attr = to_attr(dentry); 77 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
92 struct kobject * kobj = to_kobj(dentry->d_parent);
93 struct sysfs_ops * ops = buffer->ops; 78 struct sysfs_ops * ops = buffer->ops;
94 int ret = 0; 79 int ret = 0;
95 ssize_t count; 80 ssize_t count;
@@ -99,8 +84,15 @@ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer
99 if (!buffer->page) 84 if (!buffer->page)
100 return -ENOMEM; 85 return -ENOMEM;
101 86
102 buffer->event = atomic_read(&sd->s_event); 87 /* need attr_sd for attr and ops, its parent for kobj */
103 count = ops->show(kobj,attr,buffer->page); 88 if (!sysfs_get_active_two(attr_sd))
89 return -ENODEV;
90
91 buffer->event = atomic_read(&attr_sd->s_event);
92 count = ops->show(kobj, attr_sd->s_elem.attr.attr, buffer->page);
93
94 sysfs_put_active_two(attr_sd);
95
104 BUG_ON(count > (ssize_t)PAGE_SIZE); 96 BUG_ON(count > (ssize_t)PAGE_SIZE);
105 if (count >= 0) { 97 if (count >= 0) {
106 buffer->needs_read_fill = 0; 98 buffer->needs_read_fill = 0;
@@ -138,10 +130,7 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos)
138 130
139 down(&buffer->sem); 131 down(&buffer->sem);
140 if (buffer->needs_read_fill) { 132 if (buffer->needs_read_fill) {
141 if (buffer->orphaned) 133 retval = fill_read_buffer(file->f_path.dentry,buffer);
142 retval = -ENODEV;
143 else
144 retval = fill_read_buffer(file->f_path.dentry,buffer);
145 if (retval) 134 if (retval)
146 goto out; 135 goto out;
147 } 136 }
@@ -196,14 +185,23 @@ fill_write_buffer(struct sysfs_buffer * buffer, const char __user * buf, size_t
196 * passing the buffer that we acquired in fill_write_buffer(). 185 * passing the buffer that we acquired in fill_write_buffer().
197 */ 186 */
198 187
199static int 188static int
200flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count) 189flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count)
201{ 190{
202 struct attribute * attr = to_attr(dentry); 191 struct sysfs_dirent *attr_sd = dentry->d_fsdata;
203 struct kobject * kobj = to_kobj(dentry->d_parent); 192 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
204 struct sysfs_ops * ops = buffer->ops; 193 struct sysfs_ops * ops = buffer->ops;
194 int rc;
195
196 /* need attr_sd for attr and ops, its parent for kobj */
197 if (!sysfs_get_active_two(attr_sd))
198 return -ENODEV;
199
200 rc = ops->store(kobj, attr_sd->s_elem.attr.attr, buffer->page, count);
205 201
206 return ops->store(kobj,attr,buffer->page,count); 202 sysfs_put_active_two(attr_sd);
203
204 return rc;
207} 205}
208 206
209 207
@@ -231,37 +229,26 @@ sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t
231 ssize_t len; 229 ssize_t len;
232 230
233 down(&buffer->sem); 231 down(&buffer->sem);
234 if (buffer->orphaned) {
235 len = -ENODEV;
236 goto out;
237 }
238 len = fill_write_buffer(buffer, buf, count); 232 len = fill_write_buffer(buffer, buf, count);
239 if (len > 0) 233 if (len > 0)
240 len = flush_write_buffer(file->f_path.dentry, buffer, len); 234 len = flush_write_buffer(file->f_path.dentry, buffer, len);
241 if (len > 0) 235 if (len > 0)
242 *ppos += len; 236 *ppos += len;
243out:
244 up(&buffer->sem); 237 up(&buffer->sem);
245 return len; 238 return len;
246} 239}
247 240
248static int sysfs_open_file(struct inode *inode, struct file *file) 241static int sysfs_open_file(struct inode *inode, struct file *file)
249{ 242{
250 struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent); 243 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
251 struct attribute * attr = to_attr(file->f_path.dentry); 244 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
252 struct sysfs_buffer_collection *set;
253 struct sysfs_buffer * buffer; 245 struct sysfs_buffer * buffer;
254 struct sysfs_ops * ops = NULL; 246 struct sysfs_ops * ops = NULL;
255 int error = 0; 247 int error;
256
257 if (!kobj || !attr)
258 goto Einval;
259 248
260 /* Grab the module reference for this attribute if we have one */ 249 /* need attr_sd for attr and ops, its parent for kobj */
261 if (!try_module_get(attr->owner)) { 250 if (!sysfs_get_active_two(attr_sd))
262 error = -ENODEV; 251 return -ENODEV;
263 goto Done;
264 }
265 252
266 /* if the kobject has no ktype, then we assume that it is a subsystem 253 /* if the kobject has no ktype, then we assume that it is a subsystem
267 * itself, and use ops for it. 254 * itself, and use ops for it.
@@ -273,33 +260,21 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
273 else 260 else
274 ops = &subsys_sysfs_ops; 261 ops = &subsys_sysfs_ops;
275 262
263 error = -EACCES;
264
276 /* No sysfs operations, either from having no subsystem, 265 /* No sysfs operations, either from having no subsystem,
277 * or the subsystem have no operations. 266 * or the subsystem have no operations.
278 */ 267 */
279 if (!ops) 268 if (!ops)
280 goto Eaccess; 269 goto err_out;
281
282 /* make sure we have a collection to add our buffers to */
283 mutex_lock(&inode->i_mutex);
284 if (!(set = inode->i_private)) {
285 if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL))) {
286 error = -ENOMEM;
287 goto Done;
288 } else {
289 INIT_LIST_HEAD(&set->associates);
290 }
291 }
292 mutex_unlock(&inode->i_mutex);
293 270
294 /* File needs write support. 271 /* File needs write support.
295 * The inode's perms must say it's ok, 272 * The inode's perms must say it's ok,
296 * and we must have a store method. 273 * and we must have a store method.
297 */ 274 */
298 if (file->f_mode & FMODE_WRITE) { 275 if (file->f_mode & FMODE_WRITE) {
299
300 if (!(inode->i_mode & S_IWUGO) || !ops->store) 276 if (!(inode->i_mode & S_IWUGO) || !ops->store)
301 goto Eaccess; 277 goto err_out;
302
303 } 278 }
304 279
305 /* File needs read support. 280 /* File needs read support.
@@ -308,48 +283,38 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
308 */ 283 */
309 if (file->f_mode & FMODE_READ) { 284 if (file->f_mode & FMODE_READ) {
310 if (!(inode->i_mode & S_IRUGO) || !ops->show) 285 if (!(inode->i_mode & S_IRUGO) || !ops->show)
311 goto Eaccess; 286 goto err_out;
312 } 287 }
313 288
314 /* No error? Great, allocate a buffer for the file, and store it 289 /* No error? Great, allocate a buffer for the file, and store it
315 * it in file->private_data for easy access. 290 * it in file->private_data for easy access.
316 */ 291 */
292 error = -ENOMEM;
317 buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL); 293 buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL);
318 if (buffer) { 294 if (!buffer)
319 INIT_LIST_HEAD(&buffer->associates); 295 goto err_out;
320 init_MUTEX(&buffer->sem); 296
321 buffer->needs_read_fill = 1; 297 init_MUTEX(&buffer->sem);
322 buffer->ops = ops; 298 buffer->needs_read_fill = 1;
323 add_to_collection(buffer, inode); 299 buffer->ops = ops;
324 file->private_data = buffer; 300 file->private_data = buffer;
325 } else 301
326 error = -ENOMEM; 302 /* open succeeded, put active references and pin attr_sd */
327 goto Done; 303 sysfs_put_active_two(attr_sd);
328 304 sysfs_get(attr_sd);
329 Einval: 305 return 0;
330 error = -EINVAL; 306
331 goto Done; 307 err_out:
332 Eaccess: 308 sysfs_put_active_two(attr_sd);
333 error = -EACCES;
334 module_put(attr->owner);
335 Done:
336 if (error)
337 kobject_put(kobj);
338 return error; 309 return error;
339} 310}
340 311
341static int sysfs_release(struct inode * inode, struct file * filp) 312static int sysfs_release(struct inode * inode, struct file * filp)
342{ 313{
343 struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent); 314 struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
344 struct attribute * attr = to_attr(filp->f_path.dentry); 315 struct sysfs_buffer *buffer = filp->private_data;
345 struct module * owner = attr->owner;
346 struct sysfs_buffer * buffer = filp->private_data;
347 316
348 if (buffer) 317 sysfs_put(attr_sd);
349 remove_from_collection(buffer, inode);
350 kobject_put(kobj);
351 /* After this point, attr should not be accessed. */
352 module_put(owner);
353 318
354 if (buffer) { 319 if (buffer) {
355 if (buffer->page) 320 if (buffer->page)
@@ -376,57 +341,43 @@ static int sysfs_release(struct inode * inode, struct file * filp)
376static unsigned int sysfs_poll(struct file *filp, poll_table *wait) 341static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
377{ 342{
378 struct sysfs_buffer * buffer = filp->private_data; 343 struct sysfs_buffer * buffer = filp->private_data;
379 struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent); 344 struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
380 struct sysfs_dirent * sd = filp->f_path.dentry->d_fsdata; 345 struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
381 int res = 0; 346
347 /* need parent for the kobj, grab both */
348 if (!sysfs_get_active_two(attr_sd))
349 goto trigger;
382 350
383 poll_wait(filp, &kobj->poll, wait); 351 poll_wait(filp, &kobj->poll, wait);
384 352
385 if (buffer->event != atomic_read(&sd->s_event)) { 353 sysfs_put_active_two(attr_sd);
386 res = POLLERR|POLLPRI;
387 buffer->needs_read_fill = 1;
388 }
389 354
390 return res; 355 if (buffer->event != atomic_read(&attr_sd->s_event))
391} 356 goto trigger;
392 357
358 return 0;
393 359
394static struct dentry *step_down(struct dentry *dir, const char * name) 360 trigger:
395{ 361 buffer->needs_read_fill = 1;
396 struct dentry * de; 362 return POLLERR|POLLPRI;
397
398 if (dir == NULL || dir->d_inode == NULL)
399 return NULL;
400
401 mutex_lock(&dir->d_inode->i_mutex);
402 de = lookup_one_len(name, dir, strlen(name));
403 mutex_unlock(&dir->d_inode->i_mutex);
404 dput(dir);
405 if (IS_ERR(de))
406 return NULL;
407 if (de->d_inode == NULL) {
408 dput(de);
409 return NULL;
410 }
411 return de;
412} 363}
413 364
414void sysfs_notify(struct kobject * k, char *dir, char *attr) 365void sysfs_notify(struct kobject *k, char *dir, char *attr)
415{ 366{
416 struct dentry *de = k->dentry; 367 struct sysfs_dirent *sd = k->sd;
417 if (de) 368
418 dget(de); 369 mutex_lock(&sysfs_mutex);
419 if (de && dir) 370
420 de = step_down(de, dir); 371 if (sd && dir)
421 if (de && attr) 372 sd = sysfs_find_dirent(sd, dir);
422 de = step_down(de, attr); 373 if (sd && attr)
423 if (de) { 374 sd = sysfs_find_dirent(sd, attr);
424 struct sysfs_dirent * sd = de->d_fsdata; 375 if (sd) {
425 if (sd) 376 atomic_inc(&sd->s_event);
426 atomic_inc(&sd->s_event);
427 wake_up_interruptible(&k->poll); 377 wake_up_interruptible(&k->poll);
428 dput(de);
429 } 378 }
379
380 mutex_unlock(&sysfs_mutex);
430} 381}
431EXPORT_SYMBOL_GPL(sysfs_notify); 382EXPORT_SYMBOL_GPL(sysfs_notify);
432 383
@@ -440,19 +391,30 @@ const struct file_operations sysfs_file_operations = {
440}; 391};
441 392
442 393
443int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type) 394int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,
395 int type)
444{ 396{
445 struct sysfs_dirent * parent_sd = dir->d_fsdata;
446 umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG; 397 umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
447 int error = -EEXIST; 398 struct sysfs_addrm_cxt acxt;
399 struct sysfs_dirent *sd;
448 400
449 mutex_lock(&dir->d_inode->i_mutex); 401 sd = sysfs_new_dirent(attr->name, mode, type);
450 if (!sysfs_dirent_exist(parent_sd, attr->name)) 402 if (!sd)
451 error = sysfs_make_dirent(parent_sd, NULL, (void *)attr, 403 return -ENOMEM;
452 mode, type); 404 sd->s_elem.attr.attr = (void *)attr;
453 mutex_unlock(&dir->d_inode->i_mutex);
454 405
455 return error; 406 sysfs_addrm_start(&acxt, dir_sd);
407
408 if (!sysfs_find_dirent(dir_sd, attr->name)) {
409 sysfs_add_one(&acxt, sd);
410 sysfs_link_sibling(sd);
411 }
412
413 if (sysfs_addrm_finish(&acxt))
414 return 0;
415
416 sysfs_put(sd);
417 return -EEXIST;
456} 418}
457 419
458 420
@@ -464,9 +426,9 @@ int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
464 426
465int sysfs_create_file(struct kobject * kobj, const struct attribute * attr) 427int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
466{ 428{
467 BUG_ON(!kobj || !kobj->dentry || !attr); 429 BUG_ON(!kobj || !kobj->sd || !attr);
468 430
469 return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR); 431 return sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
470 432
471} 433}
472 434
@@ -480,16 +442,16 @@ int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
480int sysfs_add_file_to_group(struct kobject *kobj, 442int sysfs_add_file_to_group(struct kobject *kobj,
481 const struct attribute *attr, const char *group) 443 const struct attribute *attr, const char *group)
482{ 444{
483 struct dentry *dir; 445 struct sysfs_dirent *dir_sd;
484 int error; 446 int error;
485 447
486 dir = lookup_one_len(group, kobj->dentry, strlen(group)); 448 dir_sd = sysfs_get_dirent(kobj->sd, group);
487 if (IS_ERR(dir)) 449 if (!dir_sd)
488 error = PTR_ERR(dir); 450 return -ENOENT;
489 else { 451
490 error = sysfs_add_file(dir, attr, SYSFS_KOBJ_ATTR); 452 error = sysfs_add_file(dir_sd, attr, SYSFS_KOBJ_ATTR);
491 dput(dir); 453 sysfs_put(dir_sd);
492 } 454
493 return error; 455 return error;
494} 456}
495EXPORT_SYMBOL_GPL(sysfs_add_file_to_group); 457EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
@@ -502,30 +464,31 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
502 */ 464 */
503int sysfs_update_file(struct kobject * kobj, const struct attribute * attr) 465int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
504{ 466{
505 struct dentry * dir = kobj->dentry; 467 struct sysfs_dirent *victim_sd = NULL;
506 struct dentry * victim; 468 struct dentry *victim = NULL;
507 int res = -ENOENT; 469 int rc;
508 470
509 mutex_lock(&dir->d_inode->i_mutex); 471 rc = -ENOENT;
510 victim = lookup_one_len(attr->name, dir, strlen(attr->name)); 472 victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
511 if (!IS_ERR(victim)) { 473 if (!victim_sd)
512 /* make sure dentry is really there */ 474 goto out;
513 if (victim->d_inode && 475
514 (victim->d_parent->d_inode == dir->d_inode)) { 476 victim = sysfs_get_dentry(victim_sd);
515 victim->d_inode->i_mtime = CURRENT_TIME; 477 if (IS_ERR(victim)) {
516 fsnotify_modify(victim); 478 rc = PTR_ERR(victim);
517 res = 0; 479 victim = NULL;
518 } else 480 goto out;
519 d_drop(victim);
520
521 /**
522 * Drop the reference acquired from lookup_one_len() above.
523 */
524 dput(victim);
525 } 481 }
526 mutex_unlock(&dir->d_inode->i_mutex);
527 482
528 return res; 483 mutex_lock(&victim->d_inode->i_mutex);
484 victim->d_inode->i_mtime = CURRENT_TIME;
485 fsnotify_modify(victim);
486 mutex_unlock(&victim->d_inode->i_mutex);
487 rc = 0;
488 out:
489 dput(victim);
490 sysfs_put(victim_sd);
491 return rc;
529} 492}
530 493
531 494
@@ -538,30 +501,34 @@ int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
538 */ 501 */
539int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode) 502int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
540{ 503{
541 struct dentry *dir = kobj->dentry; 504 struct sysfs_dirent *victim_sd = NULL;
542 struct dentry *victim; 505 struct dentry *victim = NULL;
543 struct inode * inode; 506 struct inode * inode;
544 struct iattr newattrs; 507 struct iattr newattrs;
545 int res = -ENOENT; 508 int rc;
546 509
547 mutex_lock(&dir->d_inode->i_mutex); 510 rc = -ENOENT;
548 victim = lookup_one_len(attr->name, dir, strlen(attr->name)); 511 victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
549 if (!IS_ERR(victim)) { 512 if (!victim_sd)
550 if (victim->d_inode && 513 goto out;
551 (victim->d_parent->d_inode == dir->d_inode)) { 514
552 inode = victim->d_inode; 515 victim = sysfs_get_dentry(victim_sd);
553 mutex_lock(&inode->i_mutex); 516 if (IS_ERR(victim)) {
554 newattrs.ia_mode = (mode & S_IALLUGO) | 517 rc = PTR_ERR(victim);
555 (inode->i_mode & ~S_IALLUGO); 518 victim = NULL;
556 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; 519 goto out;
557 res = notify_change(victim, &newattrs);
558 mutex_unlock(&inode->i_mutex);
559 }
560 dput(victim);
561 } 520 }
562 mutex_unlock(&dir->d_inode->i_mutex);
563 521
564 return res; 522 inode = victim->d_inode;
523 mutex_lock(&inode->i_mutex);
524 newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
525 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
526 rc = notify_change(victim, &newattrs);
527 mutex_unlock(&inode->i_mutex);
528 out:
529 dput(victim);
530 sysfs_put(victim_sd);
531 return rc;
565} 532}
566EXPORT_SYMBOL_GPL(sysfs_chmod_file); 533EXPORT_SYMBOL_GPL(sysfs_chmod_file);
567 534
@@ -576,7 +543,7 @@ EXPORT_SYMBOL_GPL(sysfs_chmod_file);
576 543
577void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr) 544void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
578{ 545{
579 sysfs_hash_and_remove(kobj->dentry, attr->name); 546 sysfs_hash_and_remove(kobj->sd, attr->name);
580} 547}
581 548
582 549
@@ -589,12 +556,12 @@ void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
589void sysfs_remove_file_from_group(struct kobject *kobj, 556void sysfs_remove_file_from_group(struct kobject *kobj,
590 const struct attribute *attr, const char *group) 557 const struct attribute *attr, const char *group)
591{ 558{
592 struct dentry *dir; 559 struct sysfs_dirent *dir_sd;
593 560
594 dir = lookup_one_len(group, kobj->dentry, strlen(group)); 561 dir_sd = sysfs_get_dirent(kobj->sd, group);
595 if (!IS_ERR(dir)) { 562 if (dir_sd) {
596 sysfs_hash_and_remove(dir, attr->name); 563 sysfs_hash_and_remove(dir_sd, attr->name);
597 dput(dir); 564 sysfs_put(dir_sd);
598 } 565 }
599} 566}
600EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group); 567EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 52eed2a7a5ef..f318b73c790c 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -18,26 +18,25 @@
18#include "sysfs.h" 18#include "sysfs.h"
19 19
20 20
21static void remove_files(struct dentry * dir, 21static void remove_files(struct sysfs_dirent *dir_sd,
22 const struct attribute_group * grp) 22 const struct attribute_group *grp)
23{ 23{
24 struct attribute *const* attr; 24 struct attribute *const* attr;
25 25
26 for (attr = grp->attrs; *attr; attr++) 26 for (attr = grp->attrs; *attr; attr++)
27 sysfs_hash_and_remove(dir,(*attr)->name); 27 sysfs_hash_and_remove(dir_sd, (*attr)->name);
28} 28}
29 29
30static int create_files(struct dentry * dir, 30static int create_files(struct sysfs_dirent *dir_sd,
31 const struct attribute_group * grp) 31 const struct attribute_group *grp)
32{ 32{
33 struct attribute *const* attr; 33 struct attribute *const* attr;
34 int error = 0; 34 int error = 0;
35 35
36 for (attr = grp->attrs; *attr && !error; attr++) { 36 for (attr = grp->attrs; *attr && !error; attr++)
37 error = sysfs_add_file(dir, *attr, SYSFS_KOBJ_ATTR); 37 error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR);
38 }
39 if (error) 38 if (error)
40 remove_files(dir,grp); 39 remove_files(dir_sd, grp);
41 return error; 40 return error;
42} 41}
43 42
@@ -45,44 +44,44 @@ static int create_files(struct dentry * dir,
45int sysfs_create_group(struct kobject * kobj, 44int sysfs_create_group(struct kobject * kobj,
46 const struct attribute_group * grp) 45 const struct attribute_group * grp)
47{ 46{
48 struct dentry * dir; 47 struct sysfs_dirent *sd;
49 int error; 48 int error;
50 49
51 BUG_ON(!kobj || !kobj->dentry); 50 BUG_ON(!kobj || !kobj->sd);
52 51
53 if (grp->name) { 52 if (grp->name) {
54 error = sysfs_create_subdir(kobj,grp->name,&dir); 53 error = sysfs_create_subdir(kobj, grp->name, &sd);
55 if (error) 54 if (error)
56 return error; 55 return error;
57 } else 56 } else
58 dir = kobj->dentry; 57 sd = kobj->sd;
59 dir = dget(dir); 58 sysfs_get(sd);
60 if ((error = create_files(dir,grp))) { 59 error = create_files(sd, grp);
60 if (error) {
61 if (grp->name) 61 if (grp->name)
62 sysfs_remove_subdir(dir); 62 sysfs_remove_subdir(sd);
63 } 63 }
64 dput(dir); 64 sysfs_put(sd);
65 return error; 65 return error;
66} 66}
67 67
68void sysfs_remove_group(struct kobject * kobj, 68void sysfs_remove_group(struct kobject * kobj,
69 const struct attribute_group * grp) 69 const struct attribute_group * grp)
70{ 70{
71 struct dentry * dir; 71 struct sysfs_dirent *dir_sd = kobj->sd;
72 struct sysfs_dirent *sd;
72 73
73 if (grp->name) { 74 if (grp->name) {
74 dir = lookup_one_len_kern(grp->name, kobj->dentry, 75 sd = sysfs_get_dirent(dir_sd, grp->name);
75 strlen(grp->name)); 76 BUG_ON(!sd);
76 BUG_ON(IS_ERR(dir)); 77 } else
77 } 78 sd = sysfs_get(dir_sd);
78 else
79 dir = dget(kobj->dentry);
80 79
81 remove_files(dir,grp); 80 remove_files(sd, grp);
82 if (grp->name) 81 if (grp->name)
83 sysfs_remove_subdir(dir); 82 sysfs_remove_subdir(sd);
84 /* release the ref. taken in this routine */ 83
85 dput(dir); 84 sysfs_put(sd);
86} 85}
87 86
88 87
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index 5266eec15f6e..3756e152285a 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -133,187 +133,94 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
133 */ 133 */
134static struct lock_class_key sysfs_inode_imutex_key; 134static struct lock_class_key sysfs_inode_imutex_key;
135 135
136struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd) 136void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
137{ 137{
138 struct inode * inode = new_inode(sysfs_sb); 138 inode->i_blocks = 0;
139 if (inode) { 139 inode->i_mapping->a_ops = &sysfs_aops;
140 inode->i_blocks = 0; 140 inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
141 inode->i_mapping->a_ops = &sysfs_aops; 141 inode->i_op = &sysfs_inode_operations;
142 inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; 142 inode->i_ino = sd->s_ino;
143 inode->i_op = &sysfs_inode_operations; 143 lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key);
144 inode->i_ino = sd->s_ino; 144
145 lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key); 145 if (sd->s_iattr) {
146 146 /* sysfs_dirent has non-default attributes
147 if (sd->s_iattr) { 147 * get them for the new inode from persistent copy
148 /* sysfs_dirent has non-default attributes 148 * in sysfs_dirent
149 * get them for the new inode from persistent copy 149 */
150 * in sysfs_dirent 150 set_inode_attr(inode, sd->s_iattr);
151 */
152 set_inode_attr(inode, sd->s_iattr);
153 } else
154 set_default_inode_attr(inode, mode);
155 }
156 return inode;
157}
158
159int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *))
160{
161 int error = 0;
162 struct inode * inode = NULL;
163 if (dentry) {
164 if (!dentry->d_inode) {
165 struct sysfs_dirent * sd = dentry->d_fsdata;
166 if ((inode = sysfs_new_inode(mode, sd))) {
167 if (dentry->d_parent && dentry->d_parent->d_inode) {
168 struct inode *p_inode = dentry->d_parent->d_inode;
169 p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME;
170 }
171 goto Proceed;
172 }
173 else
174 error = -ENOMEM;
175 } else
176 error = -EEXIST;
177 } else
178 error = -ENOENT;
179 goto Done;
180
181 Proceed:
182 if (init)
183 error = init(inode);
184 if (!error) {
185 d_instantiate(dentry, inode);
186 if (S_ISDIR(mode))
187 dget(dentry); /* pin only directory dentry in core */
188 } else 151 } else
189 iput(inode); 152 set_default_inode_attr(inode, sd->s_mode);
190 Done:
191 return error;
192} 153}
193 154
194/* 155/**
195 * Get the name for corresponding element represented by the given sysfs_dirent 156 * sysfs_get_inode - get inode for sysfs_dirent
157 * @sd: sysfs_dirent to allocate inode for
158 *
159 * Get inode for @sd. If such inode doesn't exist, a new inode
160 * is allocated and basics are initialized. New inode is
161 * returned locked.
162 *
163 * LOCKING:
164 * Kernel thread context (may sleep).
165 *
166 * RETURNS:
167 * Pointer to allocated inode on success, NULL on failure.
196 */ 168 */
197const unsigned char * sysfs_get_name(struct sysfs_dirent *sd) 169struct inode * sysfs_get_inode(struct sysfs_dirent *sd)
198{ 170{
199 struct attribute * attr; 171 struct inode *inode;
200 struct bin_attribute * bin_attr;
201 struct sysfs_symlink * sl;
202
203 BUG_ON(!sd || !sd->s_element);
204
205 switch (sd->s_type) {
206 case SYSFS_DIR:
207 /* Always have a dentry so use that */
208 return sd->s_dentry->d_name.name;
209
210 case SYSFS_KOBJ_ATTR:
211 attr = sd->s_element;
212 return attr->name;
213
214 case SYSFS_KOBJ_BIN_ATTR:
215 bin_attr = sd->s_element;
216 return bin_attr->attr.name;
217 172
218 case SYSFS_KOBJ_LINK: 173 inode = iget_locked(sysfs_sb, sd->s_ino);
219 sl = sd->s_element; 174 if (inode && (inode->i_state & I_NEW))
220 return sl->link_name; 175 sysfs_init_inode(sd, inode);
221 }
222 return NULL;
223}
224 176
225static inline void orphan_all_buffers(struct inode *node) 177 return inode;
226{
227 struct sysfs_buffer_collection *set;
228 struct sysfs_buffer *buf;
229
230 mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);
231 set = node->i_private;
232 if (set) {
233 list_for_each_entry(buf, &set->associates, associates) {
234 down(&buf->sem);
235 buf->orphaned = 1;
236 up(&buf->sem);
237 }
238 }
239 mutex_unlock(&node->i_mutex);
240} 178}
241 179
242 180/**
243/* 181 * sysfs_instantiate - instantiate dentry
244 * Unhashes the dentry corresponding to given sysfs_dirent 182 * @dentry: dentry to be instantiated
245 * Called with parent inode's i_mutex held. 183 * @inode: inode associated with @sd
184 *
185 * Unlock @inode if locked and instantiate @dentry with @inode.
186 *
187 * LOCKING:
188 * None.
246 */ 189 */
247void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent) 190void sysfs_instantiate(struct dentry *dentry, struct inode *inode)
248{ 191{
249 struct dentry *dentry = NULL; 192 BUG_ON(!dentry || dentry->d_inode);
250 struct inode *inode;
251 193
252 /* We're not holding a reference to ->s_dentry dentry but the 194 if (inode->i_state & I_NEW)
253 * field will stay valid as long as sysfs_lock is held. 195 unlock_new_inode(inode);
254 */
255 spin_lock(&sysfs_lock);
256 spin_lock(&dcache_lock);
257
258 /* dget dentry if it's still alive */
259 if (sd->s_dentry && sd->s_dentry->d_inode)
260 dentry = dget_locked(sd->s_dentry);
261
262 spin_unlock(&dcache_lock);
263 spin_unlock(&sysfs_lock);
264
265 /* drop dentry */
266 if (dentry) {
267 spin_lock(&dcache_lock);
268 spin_lock(&dentry->d_lock);
269 if (!d_unhashed(dentry) && dentry->d_inode) {
270 inode = dentry->d_inode;
271 spin_lock(&inode->i_lock);
272 __iget(inode);
273 spin_unlock(&inode->i_lock);
274 dget_locked(dentry);
275 __d_drop(dentry);
276 spin_unlock(&dentry->d_lock);
277 spin_unlock(&dcache_lock);
278 simple_unlink(parent->d_inode, dentry);
279 orphan_all_buffers(inode);
280 iput(inode);
281 } else {
282 spin_unlock(&dentry->d_lock);
283 spin_unlock(&dcache_lock);
284 }
285 196
286 dput(dentry); 197 d_instantiate(dentry, inode);
287 }
288} 198}
289 199
290int sysfs_hash_and_remove(struct dentry * dir, const char * name) 200int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
291{ 201{
292 struct sysfs_dirent * sd; 202 struct sysfs_addrm_cxt acxt;
293 struct sysfs_dirent * parent_sd; 203 struct sysfs_dirent **pos, *sd;
294 int found = 0;
295 204
296 if (!dir) 205 if (!dir_sd)
297 return -ENOENT; 206 return -ENOENT;
298 207
299 if (dir->d_inode == NULL) 208 sysfs_addrm_start(&acxt, dir_sd);
300 /* no inode means this hasn't been made visible yet */ 209
301 return -ENOENT; 210 for (pos = &dir_sd->s_children; *pos; pos = &(*pos)->s_sibling) {
211 sd = *pos;
302 212
303 parent_sd = dir->d_fsdata; 213 if (!sysfs_type(sd))
304 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
305 list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
306 if (!sd->s_element)
307 continue; 214 continue;
308 if (!strcmp(sysfs_get_name(sd), name)) { 215 if (!strcmp(sd->s_name, name)) {
309 list_del_init(&sd->s_sibling); 216 *pos = sd->s_sibling;
310 sysfs_drop_dentry(sd, dir); 217 sd->s_sibling = NULL;
311 sysfs_put(sd); 218 sysfs_remove_one(&acxt, sd);
312 found = 1;
313 break; 219 break;
314 } 220 }
315 } 221 }
316 mutex_unlock(&dir->d_inode->i_mutex);
317 222
318 return found ? 0 : -ENOENT; 223 if (sysfs_addrm_finish(&acxt))
224 return 0;
225 return -ENOENT;
319} 226}
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 00ab9125d398..402cc356203c 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -19,28 +19,18 @@ struct vfsmount *sysfs_mount;
19struct super_block * sysfs_sb = NULL; 19struct super_block * sysfs_sb = NULL;
20struct kmem_cache *sysfs_dir_cachep; 20struct kmem_cache *sysfs_dir_cachep;
21 21
22static void sysfs_clear_inode(struct inode *inode);
23
24static const struct super_operations sysfs_ops = { 22static const struct super_operations sysfs_ops = {
25 .statfs = simple_statfs, 23 .statfs = simple_statfs,
26 .drop_inode = sysfs_delete_inode, 24 .drop_inode = sysfs_delete_inode,
27 .clear_inode = sysfs_clear_inode,
28}; 25};
29 26
30static struct sysfs_dirent sysfs_root = { 27struct sysfs_dirent sysfs_root = {
31 .s_sibling = LIST_HEAD_INIT(sysfs_root.s_sibling), 28 .s_count = ATOMIC_INIT(1),
32 .s_children = LIST_HEAD_INIT(sysfs_root.s_children), 29 .s_flags = SYSFS_ROOT,
33 .s_element = NULL, 30 .s_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
34 .s_type = SYSFS_ROOT,
35 .s_iattr = NULL,
36 .s_ino = 1, 31 .s_ino = 1,
37}; 32};
38 33
39static void sysfs_clear_inode(struct inode *inode)
40{
41 kfree(inode->i_private);
42}
43
44static int sysfs_fill_super(struct super_block *sb, void *data, int silent) 34static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
45{ 35{
46 struct inode *inode; 36 struct inode *inode;
@@ -53,24 +43,26 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
53 sb->s_time_gran = 1; 43 sb->s_time_gran = 1;
54 sysfs_sb = sb; 44 sysfs_sb = sb;
55 45
56 inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO, 46 inode = new_inode(sysfs_sb);
57 &sysfs_root); 47 if (!inode) {
58 if (inode) {
59 inode->i_op = &sysfs_dir_inode_operations;
60 inode->i_fop = &sysfs_dir_operations;
61 /* directory inodes start off with i_nlink == 2 (for "." entry) */
62 inc_nlink(inode);
63 } else {
64 pr_debug("sysfs: could not get root inode\n"); 48 pr_debug("sysfs: could not get root inode\n");
65 return -ENOMEM; 49 return -ENOMEM;
66 } 50 }
67 51
52 sysfs_init_inode(&sysfs_root, inode);
53
54 inode->i_op = &sysfs_dir_inode_operations;
55 inode->i_fop = &sysfs_dir_operations;
56 /* directory inodes start off with i_nlink == 2 (for "." entry) */
57 inc_nlink(inode);
58
68 root = d_alloc_root(inode); 59 root = d_alloc_root(inode);
69 if (!root) { 60 if (!root) {
70 pr_debug("%s: could not get root dentry!\n",__FUNCTION__); 61 pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
71 iput(inode); 62 iput(inode);
72 return -ENOMEM; 63 return -ENOMEM;
73 } 64 }
65 sysfs_root.s_dentry = root;
74 root->d_fsdata = &sysfs_root; 66 root->d_fsdata = &sysfs_root;
75 sb->s_root = root; 67 sb->s_root = root;
76 return 0; 68 return 0;
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 7b9c5bfde920..2f86e0422290 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -11,71 +11,39 @@
11 11
12#include "sysfs.h" 12#include "sysfs.h"
13 13
14static int object_depth(struct kobject * kobj) 14static int object_depth(struct sysfs_dirent *sd)
15{ 15{
16 struct kobject * p = kobj;
17 int depth = 0; 16 int depth = 0;
18 do { depth++; } while ((p = p->parent)); 17
18 for (; sd->s_parent; sd = sd->s_parent)
19 depth++;
20
19 return depth; 21 return depth;
20} 22}
21 23
22static int object_path_length(struct kobject * kobj) 24static int object_path_length(struct sysfs_dirent * sd)
23{ 25{
24 struct kobject * p = kobj;
25 int length = 1; 26 int length = 1;
26 do { 27
27 length += strlen(kobject_name(p)) + 1; 28 for (; sd->s_parent; sd = sd->s_parent)
28 p = p->parent; 29 length += strlen(sd->s_name) + 1;
29 } while (p); 30
30 return length; 31 return length;
31} 32}
32 33
33static void fill_object_path(struct kobject * kobj, char * buffer, int length) 34static void fill_object_path(struct sysfs_dirent *sd, char *buffer, int length)
34{ 35{
35 struct kobject * p;
36
37 --length; 36 --length;
38 for (p = kobj; p; p = p->parent) { 37 for (; sd->s_parent; sd = sd->s_parent) {
39 int cur = strlen(kobject_name(p)); 38 int cur = strlen(sd->s_name);
40 39
41 /* back up enough to print this bus id with '/' */ 40 /* back up enough to print this bus id with '/' */
42 length -= cur; 41 length -= cur;
43 strncpy(buffer + length,kobject_name(p),cur); 42 strncpy(buffer + length, sd->s_name, cur);
44 *(buffer + --length) = '/'; 43 *(buffer + --length) = '/';
45 } 44 }
46} 45}
47 46
48static int sysfs_add_link(struct dentry * parent, const char * name, struct kobject * target)
49{
50 struct sysfs_dirent * parent_sd = parent->d_fsdata;
51 struct sysfs_symlink * sl;
52 int error = 0;
53
54 error = -ENOMEM;
55 sl = kmalloc(sizeof(*sl), GFP_KERNEL);
56 if (!sl)
57 goto exit1;
58
59 sl->link_name = kmalloc(strlen(name) + 1, GFP_KERNEL);
60 if (!sl->link_name)
61 goto exit2;
62
63 strcpy(sl->link_name, name);
64 sl->target_kobj = kobject_get(target);
65
66 error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO,
67 SYSFS_KOBJ_LINK);
68 if (!error)
69 return 0;
70
71 kobject_put(target);
72 kfree(sl->link_name);
73exit2:
74 kfree(sl);
75exit1:
76 return error;
77}
78
79/** 47/**
80 * sysfs_create_link - create symlink between two objects. 48 * sysfs_create_link - create symlink between two objects.
81 * @kobj: object whose directory we're creating the link in. 49 * @kobj: object whose directory we're creating the link in.
@@ -84,24 +52,57 @@ exit1:
84 */ 52 */
85int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name) 53int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
86{ 54{
87 struct dentry *dentry = NULL; 55 struct sysfs_dirent *parent_sd = NULL;
88 int error = -EEXIST; 56 struct sysfs_dirent *target_sd = NULL;
57 struct sysfs_dirent *sd = NULL;
58 struct sysfs_addrm_cxt acxt;
59 int error;
89 60
90 BUG_ON(!name); 61 BUG_ON(!name);
91 62
92 if (!kobj) { 63 if (!kobj) {
93 if (sysfs_mount && sysfs_mount->mnt_sb) 64 if (sysfs_mount && sysfs_mount->mnt_sb)
94 dentry = sysfs_mount->mnt_sb->s_root; 65 parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
95 } else 66 } else
96 dentry = kobj->dentry; 67 parent_sd = kobj->sd;
68
69 error = -EFAULT;
70 if (!parent_sd)
71 goto out_put;
72
73 /* target->sd can go away beneath us but is protected with
74 * sysfs_assoc_lock. Fetch target_sd from it.
75 */
76 spin_lock(&sysfs_assoc_lock);
77 if (target->sd)
78 target_sd = sysfs_get(target->sd);
79 spin_unlock(&sysfs_assoc_lock);
80
81 error = -ENOENT;
82 if (!target_sd)
83 goto out_put;
84
85 error = -ENOMEM;
86 sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
87 if (!sd)
88 goto out_put;
89 sd->s_elem.symlink.target_sd = target_sd;
97 90
98 if (!dentry) 91 sysfs_addrm_start(&acxt, parent_sd);
99 return -EFAULT;
100 92
101 mutex_lock(&dentry->d_inode->i_mutex); 93 if (!sysfs_find_dirent(parent_sd, name)) {
102 if (!sysfs_dirent_exist(dentry->d_fsdata, name)) 94 sysfs_add_one(&acxt, sd);
103 error = sysfs_add_link(dentry, name, target); 95 sysfs_link_sibling(sd);
104 mutex_unlock(&dentry->d_inode->i_mutex); 96 }
97
98 if (sysfs_addrm_finish(&acxt))
99 return 0;
100
101 error = -EEXIST;
102 /* fall through */
103 out_put:
104 sysfs_put(target_sd);
105 sysfs_put(sd);
105 return error; 106 return error;
106} 107}
107 108
@@ -114,17 +115,17 @@ int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char
114 115
115void sysfs_remove_link(struct kobject * kobj, const char * name) 116void sysfs_remove_link(struct kobject * kobj, const char * name)
116{ 117{
117 sysfs_hash_and_remove(kobj->dentry,name); 118 sysfs_hash_and_remove(kobj->sd, name);
118} 119}
119 120
120static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target, 121static int sysfs_get_target_path(struct sysfs_dirent * parent_sd,
121 char *path) 122 struct sysfs_dirent * target_sd, char *path)
122{ 123{
123 char * s; 124 char * s;
124 int depth, size; 125 int depth, size;
125 126
126 depth = object_depth(kobj); 127 depth = object_depth(parent_sd);
127 size = object_path_length(target) + depth * 3 - 1; 128 size = object_path_length(target_sd) + depth * 3 - 1;
128 if (size > PATH_MAX) 129 if (size > PATH_MAX)
129 return -ENAMETOOLONG; 130 return -ENAMETOOLONG;
130 131
@@ -133,7 +134,7 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
133 for (s = path; depth--; s += 3) 134 for (s = path; depth--; s += 3)
134 strcpy(s,"../"); 135 strcpy(s,"../");
135 136
136 fill_object_path(target, path, size); 137 fill_object_path(target_sd, path, size);
137 pr_debug("%s: path = '%s'\n", __FUNCTION__, path); 138 pr_debug("%s: path = '%s'\n", __FUNCTION__, path);
138 139
139 return 0; 140 return 0;
@@ -141,27 +142,16 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
141 142
142static int sysfs_getlink(struct dentry *dentry, char * path) 143static int sysfs_getlink(struct dentry *dentry, char * path)
143{ 144{
144 struct kobject *kobj, *target_kobj; 145 struct sysfs_dirent *sd = dentry->d_fsdata;
145 int error = 0; 146 struct sysfs_dirent *parent_sd = sd->s_parent;
147 struct sysfs_dirent *target_sd = sd->s_elem.symlink.target_sd;
148 int error;
146 149
147 kobj = sysfs_get_kobject(dentry->d_parent); 150 mutex_lock(&sysfs_mutex);
148 if (!kobj) 151 error = sysfs_get_target_path(parent_sd, target_sd, path);
149 return -EINVAL; 152 mutex_unlock(&sysfs_mutex);
150 153
151 target_kobj = sysfs_get_kobject(dentry);
152 if (!target_kobj) {
153 kobject_put(kobj);
154 return -EINVAL;
155 }
156
157 down_read(&sysfs_rename_sem);
158 error = sysfs_get_target_path(kobj, target_kobj, path);
159 up_read(&sysfs_rename_sem);
160
161 kobject_put(kobj);
162 kobject_put(target_kobj);
163 return error; 154 return error;
164
165} 155}
166 156
167static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) 157static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 502c949c402d..6a37f2386a8d 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -1,9 +1,40 @@
1struct sysfs_elem_dir {
2 struct kobject * kobj;
3};
4
5struct sysfs_elem_symlink {
6 struct sysfs_dirent * target_sd;
7};
8
9struct sysfs_elem_attr {
10 struct attribute * attr;
11};
12
13struct sysfs_elem_bin_attr {
14 struct bin_attribute * bin_attr;
15};
16
17/*
18 * As long as s_count reference is held, the sysfs_dirent itself is
19 * accessible. Dereferencing s_elem or any other outer entity
20 * requires s_active reference.
21 */
1struct sysfs_dirent { 22struct sysfs_dirent {
2 atomic_t s_count; 23 atomic_t s_count;
3 struct list_head s_sibling; 24 atomic_t s_active;
4 struct list_head s_children; 25 struct sysfs_dirent * s_parent;
5 void * s_element; 26 struct sysfs_dirent * s_sibling;
6 int s_type; 27 struct sysfs_dirent * s_children;
28 const char * s_name;
29
30 union {
31 struct sysfs_elem_dir dir;
32 struct sysfs_elem_symlink symlink;
33 struct sysfs_elem_attr attr;
34 struct sysfs_elem_bin_attr bin_attr;
35 } s_elem;
36
37 unsigned int s_flags;
7 umode_t s_mode; 38 umode_t s_mode;
8 ino_t s_ino; 39 ino_t s_ino;
9 struct dentry * s_dentry; 40 struct dentry * s_dentry;
@@ -11,30 +42,60 @@ struct sysfs_dirent {
11 atomic_t s_event; 42 atomic_t s_event;
12}; 43};
13 44
45#define SD_DEACTIVATED_BIAS INT_MIN
46
47struct sysfs_addrm_cxt {
48 struct sysfs_dirent *parent_sd;
49 struct inode *parent_inode;
50 struct sysfs_dirent *removed;
51 int cnt;
52};
53
14extern struct vfsmount * sysfs_mount; 54extern struct vfsmount * sysfs_mount;
55extern struct sysfs_dirent sysfs_root;
15extern struct kmem_cache *sysfs_dir_cachep; 56extern struct kmem_cache *sysfs_dir_cachep;
16 57
17extern void sysfs_delete_inode(struct inode *inode); 58extern struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
18extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *); 59extern void sysfs_link_sibling(struct sysfs_dirent *sd);
19extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *)); 60extern void sysfs_unlink_sibling(struct sysfs_dirent *sd);
61extern struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
62extern void sysfs_put_active(struct sysfs_dirent *sd);
63extern struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
64extern void sysfs_put_active_two(struct sysfs_dirent *sd);
65extern void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
66 struct sysfs_dirent *parent_sd);
67extern void sysfs_add_one(struct sysfs_addrm_cxt *acxt,
68 struct sysfs_dirent *sd);
69extern void sysfs_remove_one(struct sysfs_addrm_cxt *acxt,
70 struct sysfs_dirent *sd);
71extern int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
20 72
21extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *); 73extern void sysfs_delete_inode(struct inode *inode);
22extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *, 74extern void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode);
23 umode_t, int); 75extern struct inode * sysfs_get_inode(struct sysfs_dirent *sd);
24 76extern void sysfs_instantiate(struct dentry *dentry, struct inode *inode);
25extern int sysfs_add_file(struct dentry *, const struct attribute *, int); 77
26extern int sysfs_hash_and_remove(struct dentry * dir, const char * name); 78extern void release_sysfs_dirent(struct sysfs_dirent * sd);
79extern struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
80 const unsigned char *name);
81extern struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
82 const unsigned char *name);
83extern struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode,
84 int type);
85
86extern int sysfs_add_file(struct sysfs_dirent *dir_sd,
87 const struct attribute *attr, int type);
88extern int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
27extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name); 89extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
28 90
29extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **); 91extern int sysfs_create_subdir(struct kobject *kobj, const char *name,
30extern void sysfs_remove_subdir(struct dentry *); 92 struct sysfs_dirent **p_sd);
93extern void sysfs_remove_subdir(struct sysfs_dirent *sd);
31 94
32extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
33extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
34extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); 95extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
35 96
36extern spinlock_t sysfs_lock; 97extern spinlock_t sysfs_assoc_lock;
37extern struct rw_semaphore sysfs_rename_sem; 98extern struct mutex sysfs_mutex;
38extern struct super_block * sysfs_sb; 99extern struct super_block * sysfs_sb;
39extern const struct file_operations sysfs_dir_operations; 100extern const struct file_operations sysfs_dir_operations;
40extern const struct file_operations sysfs_file_operations; 101extern const struct file_operations sysfs_file_operations;
@@ -42,73 +103,9 @@ extern const struct file_operations bin_fops;
42extern const struct inode_operations sysfs_dir_inode_operations; 103extern const struct inode_operations sysfs_dir_inode_operations;
43extern const struct inode_operations sysfs_symlink_inode_operations; 104extern const struct inode_operations sysfs_symlink_inode_operations;
44 105
45struct sysfs_symlink { 106static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
46 char * link_name;
47 struct kobject * target_kobj;
48};
49
50struct sysfs_buffer {
51 struct list_head associates;
52 size_t count;
53 loff_t pos;
54 char * page;
55 struct sysfs_ops * ops;
56 struct semaphore sem;
57 int orphaned;
58 int needs_read_fill;
59 int event;
60};
61
62struct sysfs_buffer_collection {
63 struct list_head associates;
64};
65
66static inline struct kobject * to_kobj(struct dentry * dentry)
67{
68 struct sysfs_dirent * sd = dentry->d_fsdata;
69 return ((struct kobject *) sd->s_element);
70}
71
72static inline struct attribute * to_attr(struct dentry * dentry)
73{ 107{
74 struct sysfs_dirent * sd = dentry->d_fsdata; 108 return sd->s_flags & SYSFS_TYPE_MASK;
75 return ((struct attribute *) sd->s_element);
76}
77
78static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
79{
80 struct sysfs_dirent * sd = dentry->d_fsdata;
81 return ((struct bin_attribute *) sd->s_element);
82}
83
84static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
85{
86 struct kobject * kobj = NULL;
87
88 spin_lock(&dcache_lock);
89 if (!d_unhashed(dentry)) {
90 struct sysfs_dirent * sd = dentry->d_fsdata;
91 if (sd->s_type & SYSFS_KOBJ_LINK) {
92 struct sysfs_symlink * sl = sd->s_element;
93 kobj = kobject_get(sl->target_kobj);
94 } else
95 kobj = kobject_get(sd->s_element);
96 }
97 spin_unlock(&dcache_lock);
98
99 return kobj;
100}
101
102static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
103{
104 if (sd->s_type & SYSFS_KOBJ_LINK) {
105 struct sysfs_symlink * sl = sd->s_element;
106 kfree(sl->link_name);
107 kobject_put(sl->target_kobj);
108 kfree(sl);
109 }
110 kfree(sd->s_iattr);
111 kmem_cache_free(sysfs_dir_cachep, sd);
112} 109}
113 110
114static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd) 111static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
@@ -122,7 +119,7 @@ static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
122 119
123static inline void sysfs_put(struct sysfs_dirent * sd) 120static inline void sysfs_put(struct sysfs_dirent * sd)
124{ 121{
125 if (atomic_dec_and_test(&sd->s_count)) 122 if (sd && atomic_dec_and_test(&sd->s_count))
126 release_sysfs_dirent(sd); 123 release_sysfs_dirent(sd);
127} 124}
128 125
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-19 17:46:38 -0500