Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 705 insertions, 0 deletions

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
new file mode 100644
index 000000000000..6c6315d04028
--- /dev/null
+++ b/fs/proc/generic.c
@@ -0,0 +1,705 @@
+/*
+ * proc/fs/generic.c --- generic routines for the proc-fs
+ *
+ * This file contains generic proc-fs routines for handling
+ * directories and files.
+ * 
+ * Copyright (C) 1991, 1992 Linus Torvalds.
+ * Copyright (C) 1997 Theodore Ts'o
+ */
+
+#include <linux/errno.h>
+#include <linux/time.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/module.h>
+#include <linux/mount.h>
+#include <linux/smp_lock.h>
+#include <linux/init.h>
+#include <linux/idr.h>
+#include <linux/namei.h>
+#include <linux/bitops.h>
+#include <asm/uaccess.h>
+
+static ssize_t proc_file_read(struct file *file, char __user *buf,
+                              size_t nbytes, loff_t *ppos);
+static ssize_t proc_file_write(struct file *file, const char __user *buffer,
+                               size_t count, loff_t *ppos);
+static loff_t proc_file_lseek(struct file *, loff_t, int);
+
+int proc_match(int len, const char *name, struct proc_dir_entry *de)
+{
+        if (de->namelen != len)
+                return 0;
+        return !memcmp(name, de->name, len);
+}
+
+static struct file_operations proc_file_operations = {
+        .llseek         = proc_file_lseek,
+        .read           = proc_file_read,
+        .write          = proc_file_write,
+};
+
+/* buffer size is one page but our output routines use some slack for overruns */
+#define PROC_BLOCK_SIZE (PAGE_SIZE - 1024)
+
+static ssize_t
+proc_file_read(struct file *file, char __user *buf, size_t nbytes,
+               loff_t *ppos)
+{
+        struct inode * inode = file->f_dentry->d_inode;
+        char    *page;
+        ssize_t retval=0;
+        int     eof=0;
+        ssize_t n, count;
+        char    *start;
+        struct proc_dir_entry * dp;
+
+        dp = PDE(inode);
+        if (!(page = (char*) __get_free_page(GFP_KERNEL)))
+                return -ENOMEM;
+
+        while ((nbytes > 0) && !eof) {
+                count = min_t(size_t, PROC_BLOCK_SIZE, nbytes);
+
+                start = NULL;
+                if (dp->get_info) {
+                        /* Handle old net routines */
+                        n = dp->get_info(page, &start, *ppos, count);
+                        if (n < count)
+                                eof = 1;
+                } else if (dp->read_proc) {
+                        /*
+                         * How to be a proc read function
+                         * ------------------------------
+                         * Prototype:
+                         *    int f(char *buffer, char **start, off_t offset,
+                         *          int count, int *peof, void *dat)
+                         *
+                         * Assume that the buffer is "count" bytes in size.
+                         *
+                         * If you know you have supplied all the data you
+                         * have, set *peof.
+                         *
+                         * You have three ways to return data:
+                         * 0) Leave *start = NULL.  (This is the default.)
+                         *    Put the data of the requested offset at that
+                         *    offset within the buffer.  Return the number (n)
+                         *    of bytes there are from the beginning of the
+                         *    buffer up to the last byte of data.  If the
+                         *    number of supplied bytes (= n - offset) is 
+                         *    greater than zero and you didn't signal eof
+                         *    and the reader is prepared to take more data
+                         *    you will be called again with the requested
+                         *    offset advanced by the number of bytes 
+                         *    absorbed.  This interface is useful for files
+                         *    no larger than the buffer.
+                         * 1) Set *start = an unsigned long value less than
+                         *    the buffer address but greater than zero.
+                         *    Put the data of the requested offset at the
+                         *    beginning of the buffer.  Return the number of
+                         *    bytes of data placed there.  If this number is
+                         *    greater than zero and you didn't signal eof
+                         *    and the reader is prepared to take more data
+                         *    you will be called again with the requested
+                         *    offset advanced by *start.  This interface is
+                         *    useful when you have a large file consisting
+                         *    of a series of blocks which you want to count
+                         *    and return as wholes.
+                         *    (Hack by Paul.Russell@rustcorp.com.au)
+                         * 2) Set *start = an address within the buffer.
+                         *    Put the data of the requested offset at *start.
+                         *    Return the number of bytes of data placed there.
+                         *    If this number is greater than zero and you
+                         *    didn't signal eof and the reader is prepared to
+                         *    take more data you will be called again with the
+                         *    requested offset advanced by the number of bytes
+                         *    absorbed.
+                         */
+                        n = dp->read_proc(page, &start, *ppos,
+                                          count, &eof, dp->data);
+                } else
+                        break;
+
+                if (n == 0)   /* end of file */
+                        break;
+                if (n < 0) {  /* error */
+                        if (retval == 0)
+                                retval = n;
+                        break;
+                }
+
+                if (start == NULL) {
+                        if (n > PAGE_SIZE) {
+                                printk(KERN_ERR
+                                       "proc_file_read: Apparent buffer overflow!\n");
+                                n = PAGE_SIZE;
+                        }
+                        n -= *ppos;
+                        if (n <= 0)
+                                break;
+                        if (n > count)
+                                n = count;
+                        start = page + *ppos;
+                } else if (start < page) {
+                        if (n > PAGE_SIZE) {
+                                printk(KERN_ERR
+                                       "proc_file_read: Apparent buffer overflow!\n");
+                                n = PAGE_SIZE;
+                        }
+                        if (n > count) {
+                                /*
+                                 * Don't reduce n because doing so might
+                                 * cut off part of a data block.
+                                 */
+                                printk(KERN_WARNING
+                                       "proc_file_read: Read count exceeded\n");
+                        }
+                } else /* start >= page */ {
+                        unsigned long startoff = (unsigned long)(start - page);
+                        if (n > (PAGE_SIZE - startoff)) {
+                                printk(KERN_ERR
+                                       "proc_file_read: Apparent buffer overflow!\n");
+                                n = PAGE_SIZE - startoff;
+                        }
+                        if (n > count)
+                                n = count;
+                }
+                
+                n -= copy_to_user(buf, start < page ? page : start, n);
+                if (n == 0) {
+                        if (retval == 0)
+                                retval = -EFAULT;
+                        break;
+                }
+
+                *ppos += start < page ? (unsigned long)start : n;
+                nbytes -= n;
+                buf += n;
+                retval += n;
+        }
+        free_page((unsigned long) page);
+        return retval;
+}
+
+static ssize_t
+proc_file_write(struct file *file, const char __user *buffer,
+                size_t count, loff_t *ppos)
+{
+        struct inode *inode = file->f_dentry->d_inode;
+        struct proc_dir_entry * dp;
+        
+        dp = PDE(inode);
+
+        if (!dp->write_proc)
+                return -EIO;
+
+        /* FIXME: does this routine need ppos?  probably... */
+        return dp->write_proc(file, buffer, count, dp->data);
+}
+
+
+static loff_t
+proc_file_lseek(struct file *file, loff_t offset, int orig)
+{
+    lock_kernel();
+
+    switch (orig) {
+    case 0:
+        if (offset < 0)
+            goto out;
+        file->f_pos = offset;
+        unlock_kernel();
+        return(file->f_pos);
+    case 1:
+        if (offset + file->f_pos < 0)
+            goto out;
+        file->f_pos += offset;
+        unlock_kernel();
+        return(file->f_pos);
+    case 2:
+        goto out;
+    default:
+        goto out;
+    }
+
+out:
+    unlock_kernel();
+    return -EINVAL;
+}
+
+static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
+{
+        struct inode *inode = dentry->d_inode;
+        struct proc_dir_entry *de = PDE(inode);
+        int error;
+
+        error = inode_change_ok(inode, iattr);
+        if (error)
+                goto out;
+
+        error = inode_setattr(inode, iattr);
+        if (error)
+                goto out;
+        
+        de->uid = inode->i_uid;
+        de->gid = inode->i_gid;
+        de->mode = inode->i_mode;
+out:
+        return error;
+}
+
+static struct inode_operations proc_file_inode_operations = {
+        .setattr        = proc_notify_change,
+};
+
+/*
+ * This function parses a name such as "tty/driver/serial", and
+ * returns the struct proc_dir_entry for "/proc/tty/driver", and
+ * returns "serial" in residual.
+ */
+static int xlate_proc_name(const char *name,
+                           struct proc_dir_entry **ret, const char **residual)
+{
+        const char              *cp = name, *next;
+        struct proc_dir_entry   *de;
+        int                     len;
+
+        de = &proc_root;
+        while (1) {
+                next = strchr(cp, '/');
+                if (!next)
+                        break;
+
+                len = next - cp;
+                for (de = de->subdir; de ; de = de->next) {
+                        if (proc_match(len, cp, de))
+                                break;
+                }
+                if (!de)
+                        return -ENOENT;
+                cp += len + 1;
+        }
+        *residual = cp;
+        *ret = de;
+        return 0;
+}
+
+static DEFINE_IDR(proc_inum_idr);
+static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
+
+#define PROC_DYNAMIC_FIRST 0xF0000000UL
+
+/*
+ * Return an inode number between PROC_DYNAMIC_FIRST and
+ * 0xffffffff, or zero on failure.
+ */
+static unsigned int get_inode_number(void)
+{
+        int i, inum = 0;
+        int error;
+
+retry:
+        if (idr_pre_get(&proc_inum_idr, GFP_KERNEL) == 0)
+                return 0;
+
+        spin_lock(&proc_inum_lock);
+        error = idr_get_new(&proc_inum_idr, NULL, &i);
+        spin_unlock(&proc_inum_lock);
+        if (error == -EAGAIN)
+                goto retry;
+        else if (error)
+                return 0;
+
+        inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST;
+
+        /* inum will never be more than 0xf0ffffff, so no check
+         * for overflow.
+         */
+
+        return inum;
+}
+
+static void release_inode_number(unsigned int inum)
+{
+        int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK;
+
+        spin_lock(&proc_inum_lock);
+        idr_remove(&proc_inum_idr, id);
+        spin_unlock(&proc_inum_lock);
+}
+
+static int proc_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+        nd_set_link(nd, PDE(dentry->d_inode)->data);
+        return 0;
+}
+
+static struct inode_operations proc_link_inode_operations = {
+        .readlink       = generic_readlink,
+        .follow_link    = proc_follow_link,
+};
+
+/*
+ * As some entries in /proc are volatile, we want to 
+ * get rid of unused dentries.  This could be made 
+ * smarter: we could keep a "volatile" flag in the 
+ * inode to indicate which ones to keep.
+ */
+static int proc_delete_dentry(struct dentry * dentry)
+{
+        return 1;
+}
+
+static struct dentry_operations proc_dentry_operations =
+{
+        .d_delete       = proc_delete_dentry,
+};
+
+/*
+ * Don't create negative dentries here, return -ENOENT by hand
+ * instead.
+ */
+struct dentry *proc_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
+{
+        struct inode *inode = NULL;
+        struct proc_dir_entry * de;
+        int error = -ENOENT;
+
+        lock_kernel();
+        de = PDE(dir);
+        if (de) {
+                for (de = de->subdir; de ; de = de->next) {
+                        if (de->namelen != dentry->d_name.len)
+                                continue;
+                        if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
+                                unsigned int ino = de->low_ino;
+
+                                error = -EINVAL;
+                                inode = proc_get_inode(dir->i_sb, ino, de);
+                                break;
+                        }
+                }
+        }
+        unlock_kernel();
+
+        if (inode) {
+                dentry->d_op = &proc_dentry_operations;
+                d_add(dentry, inode);
+                return NULL;
+        }
+        return ERR_PTR(error);
+}
+
+/*
+ * This returns non-zero if at EOF, so that the /proc
+ * root directory can use this and check if it should
+ * continue with the <pid> entries..
+ *
+ * Note that the VFS-layer doesn't care about the return
+ * value of the readdir() call, as long as it's non-negative
+ * for success..
+ */
+int proc_readdir(struct file * filp,
+        void * dirent, filldir_t filldir)
+{
+        struct proc_dir_entry * de;
+        unsigned int ino;
+        int i;
+        struct inode *inode = filp->f_dentry->d_inode;
+        int ret = 0;
+
+        lock_kernel();
+
+        ino = inode->i_ino;
+        de = PDE(inode);
+        if (!de) {
+                ret = -EINVAL;
+                goto out;
+        }
+        i = filp->f_pos;
+        switch (i) {
+                case 0:
+                        if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+                                goto out;
+                        i++;
+                        filp->f_pos++;
+                        /* fall through */
+                case 1:
+                        if (filldir(dirent, "..", 2, i,
+                                    parent_ino(filp->f_dentry),
+                                    DT_DIR) < 0)
+                                goto out;
+                        i++;
+                        filp->f_pos++;
+                        /* fall through */
+                default:
+                        de = de->subdir;
+                        i -= 2;
+                        for (;;) {
+                                if (!de) {
+                                        ret = 1;
+                                        goto out;
+                                }
+                                if (!i)
+                                        break;
+                                de = de->next;
+                                i--;
+                        }
+
+                        do {
+                                if (filldir(dirent, de->name, de->namelen, filp->f_pos,
+                                            de->low_ino, de->mode >> 12) < 0)
+                                        goto out;
+                                filp->f_pos++;
+                                de = de->next;
+                        } while (de);
+        }
+        ret = 1;
+out:    unlock_kernel();
+        return ret;     
+}
+
+/*
+ * These are the generic /proc directory operations. They
+ * use the in-memory "struct proc_dir_entry" tree to parse
+ * the /proc directory.
+ */
+static struct file_operations proc_dir_operations = {
+        .read                   = generic_read_dir,
+        .readdir                = proc_readdir,
+};
+
+/*
+ * proc directories can do almost nothing..
+ */
+static struct inode_operations proc_dir_inode_operations = {
+        .lookup         = proc_lookup,
+        .setattr        = proc_notify_change,
+};
+
+static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp)
+{
+        unsigned int i;
+        
+        i = get_inode_number();
+        if (i == 0)
+                return -EAGAIN;
+        dp->low_ino = i;
+        dp->next = dir->subdir;
+        dp->parent = dir;
+        dir->subdir = dp;
+        if (S_ISDIR(dp->mode)) {
+                if (dp->proc_iops == NULL) {
+                        dp->proc_fops = &proc_dir_operations;
+                        dp->proc_iops = &proc_dir_inode_operations;
+                }
+                dir->nlink++;
+        } else if (S_ISLNK(dp->mode)) {
+                if (dp->proc_iops == NULL)
+                        dp->proc_iops = &proc_link_inode_operations;
+        } else if (S_ISREG(dp->mode)) {
+                if (dp->proc_fops == NULL)
+                        dp->proc_fops = &proc_file_operations;
+                if (dp->proc_iops == NULL)
+                        dp->proc_iops = &proc_file_inode_operations;
+        }
+        return 0;
+}
+
+/*
+ * Kill an inode that got unregistered..
+ */
+static void proc_kill_inodes(struct proc_dir_entry *de)
+{
+        struct list_head *p;
+        struct super_block *sb = proc_mnt->mnt_sb;
+
+        /*
+         * Actually it's a partial revoke().
+         */
+        file_list_lock();
+        list_for_each(p, &sb->s_files) {
+                struct file * filp = list_entry(p, struct file, f_list);
+                struct dentry * dentry = filp->f_dentry;
+                struct inode * inode;
+                struct file_operations *fops;
+
+                if (dentry->d_op != &proc_dentry_operations)
+                        continue;
+                inode = dentry->d_inode;
+                if (PDE(inode) != de)
+                        continue;
+                fops = filp->f_op;
+                filp->f_op = NULL;
+                fops_put(fops);
+        }
+        file_list_unlock();
+}
+
+static struct proc_dir_entry *proc_create(struct proc_dir_entry **parent,
+                                          const char *name,
+                                          mode_t mode,
+                                          nlink_t nlink)
+{
+        struct proc_dir_entry *ent = NULL;
+        const char *fn = name;
+        int len;
+
+        /* make sure name is valid */
+        if (!name || !strlen(name)) goto out;
+
+        if (!(*parent) && xlate_proc_name(name, parent, &fn) != 0)
+                goto out;
+
+        /* At this point there must not be any '/' characters beyond *fn */
+        if (strchr(fn, '/'))
+                goto out;
+
+        len = strlen(fn);
+
+        ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL);
+        if (!ent) goto out;
+
+        memset(ent, 0, sizeof(struct proc_dir_entry));
+        memcpy(((char *) ent) + sizeof(struct proc_dir_entry), fn, len + 1);
+        ent->name = ((char *) ent) + sizeof(*ent);
+        ent->namelen = len;
+        ent->mode = mode;
+        ent->nlink = nlink;
+ out:
+        return ent;
+}
+
+struct proc_dir_entry *proc_symlink(const char *name,
+                struct proc_dir_entry *parent, const char *dest)
+{
+        struct proc_dir_entry *ent;
+
+        ent = proc_create(&parent,name,
+                          (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1);
+
+        if (ent) {
+                ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL);
+                if (ent->data) {
+                        strcpy((char*)ent->data,dest);
+                        if (proc_register(parent, ent) < 0) {
+                                kfree(ent->data);
+                                kfree(ent);
+                                ent = NULL;
+                        }
+                } else {
+                        kfree(ent);
+                        ent = NULL;
+                }
+        }
+        return ent;
+}
+
+struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
+                struct proc_dir_entry *parent)
+{
+        struct proc_dir_entry *ent;
+
+        ent = proc_create(&parent, name, S_IFDIR | mode, 2);
+        if (ent) {
+                ent->proc_fops = &proc_dir_operations;
+                ent->proc_iops = &proc_dir_inode_operations;
+
+                if (proc_register(parent, ent) < 0) {
+                        kfree(ent);
+                        ent = NULL;
+                }
+        }
+        return ent;
+}
+
+struct proc_dir_entry *proc_mkdir(const char *name,
+                struct proc_dir_entry *parent)
+{
+        return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent);
+}
+
+struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
+                                         struct proc_dir_entry *parent)
+{
+        struct proc_dir_entry *ent;
+        nlink_t nlink;
+
+        if (S_ISDIR(mode)) {
+                if ((mode & S_IALLUGO) == 0)
+                        mode |= S_IRUGO | S_IXUGO;
+                nlink = 2;
+        } else {
+                if ((mode & S_IFMT) == 0)
+                        mode |= S_IFREG;
+                if ((mode & S_IALLUGO) == 0)
+                        mode |= S_IRUGO;
+                nlink = 1;
+        }
+
+        ent = proc_create(&parent,name,mode,nlink);
+        if (ent) {
+                if (S_ISDIR(mode)) {
+                        ent->proc_fops = &proc_dir_operations;
+                        ent->proc_iops = &proc_dir_inode_operations;
+                }
+                if (proc_register(parent, ent) < 0) {
+                        kfree(ent);
+                        ent = NULL;
+                }
+        }
+        return ent;
+}
+
+void free_proc_entry(struct proc_dir_entry *de)
+{
+        unsigned int ino = de->low_ino;
+
+        if (ino < PROC_DYNAMIC_FIRST)
+                return;
+
+        release_inode_number(ino);
+
+        if (S_ISLNK(de->mode) && de->data)
+                kfree(de->data);
+        kfree(de);
+}
+
+/*
+ * Remove a /proc entry and free it if it's not currently in use.
+ * If it is in use, we set the 'deleted' flag.
+ */
+void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+{
+        struct proc_dir_entry **p;
+        struct proc_dir_entry *de;
+        const char *fn = name;
+        int len;
+
+        if (!parent && xlate_proc_name(name, &parent, &fn) != 0)
+                goto out;
+        len = strlen(fn);
+        for (p = &parent->subdir; *p; p=&(*p)->next ) {
+                if (!proc_match(len, fn, *p))
+                        continue;
+                de = *p;
+                *p = de->next;
+                de->next = NULL;
+                if (S_ISDIR(de->mode))
+                        parent->nlink--;
+                proc_kill_inodes(de);
+                de->nlink = 0;
+                WARN_ON(de->subdir);
+                if (!atomic_read(&de->count))
+                        free_proc_entry(de);
+                else {
+                        de->deleted = 1;
+                        printk("remove_proc_entry: %s/%s busy, count=%d\n",
+                                parent->name, de->name, atomic_read(&de->count));
+                }
+                break;
+        }
+out:
+        return;
+}