1 files changed, 86 insertions, 106 deletions

diff --git a/fs/locks.c b/fs/locks.c
index c795eaaf6c4c..7f9a3ea47418 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -534,7 +534,9 @@ static void locks_insert_block(struct file_lock *blocker,
 static void locks_wake_up_blocks(struct file_lock *blocker)
 {
         while (!list_empty(&blocker->fl_block)) {
-                struct file_lock *waiter = list_entry(blocker->fl_block.next,
+                struct file_lock *waiter;
+
+                waiter = list_first_entry(&blocker->fl_block,
                                 struct file_lock, fl_block);
                 __locks_delete_block(waiter);
                 if (waiter->fl_lmops && waiter->fl_lmops->fl_notify)
@@ -668,7 +670,7 @@ posix_test_lock(struct file *filp, struct file_lock *fl)
         for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
                 if (!IS_POSIX(cfl))
                         continue;
-                if (posix_locks_conflict(cfl, fl))
+                if (posix_locks_conflict(fl, cfl))
                         break;
         }
         if (cfl)
@@ -698,13 +700,12 @@ EXPORT_SYMBOL(posix_test_lock);
 static int posix_locks_deadlock(struct file_lock *caller_fl,
                                 struct file_lock *block_fl)
 {
-        struct list_head *tmp;
+        struct file_lock *fl;
 
 next_task:
         if (posix_same_owner(caller_fl, block_fl))
                 return 1;
-        list_for_each(tmp, &blocked_list) {
-                struct file_lock *fl = list_entry(tmp, struct file_lock, fl_link);
+        list_for_each_entry(fl, &blocked_list, fl_link) {
                 if (posix_same_owner(fl, block_fl)) {
                         fl = fl->fl_next;
                         block_fl = fl;
@@ -715,8 +716,7 @@ next_task:
 }
 
 /* Try to create a FLOCK lock on filp. We always insert new FLOCK locks
- * at the head of the list, but that's secret knowledge known only to
- * flock_lock_file and posix_lock_file.
+ * after any leases, but before any posix locks.
  *
  * Note that if called with an FL_EXISTS argument, the caller may determine
  * whether or not a lock was successfully freed by testing the return
@@ -733,6 +733,15 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
         lock_kernel();
         if (request->fl_flags & FL_ACCESS)
                 goto find_conflict;
+
+        if (request->fl_type != F_UNLCK) {
+                error = -ENOMEM;
+                new_fl = locks_alloc_lock();
+                if (new_fl == NULL)
+                        goto out;
+                error = 0;
+        }
+
         for_each_lock(inode, before) {
                 struct file_lock *fl = *before;
                 if (IS_POSIX(fl))
@@ -754,10 +763,6 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
                 goto out;
         }
 
-        error = -ENOMEM;
-        new_fl = locks_alloc_lock();
-        if (new_fl == NULL)
-                goto out;
         /*
          * If a higher-priority process was blocked on the old file lock,
          * give it the opportunity to lock the file.
@@ -819,7 +824,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
         lock_kernel();
         if (request->fl_type != F_UNLCK) {
                 for_each_lock(inode, before) {
-                        struct file_lock *fl = *before;
+                        fl = *before;
                         if (!IS_POSIX(fl))
                                 continue;
                         if (!posix_locks_conflict(request, fl))
@@ -1113,7 +1118,7 @@ int locks_mandatory_area(int read_write, struct inode *inode,
                          * If we've been sleeping someone might have
                          * changed the permissions behind our back.
                          */
-                        if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+                        if (__mandatory_lock(inode))
                                 continue;
                 }
 
@@ -1337,6 +1342,7 @@ int fcntl_getlease(struct file *filp)
 int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 {
         struct file_lock *fl, **before, **my_before = NULL, *lease;
+        struct file_lock *new_fl = NULL;
         struct dentry *dentry = filp->f_path.dentry;
         struct inode *inode = dentry->d_inode;
         int error, rdlease_count = 0, wrlease_count = 0;
@@ -1363,6 +1369,11 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
                 || (atomic_read(&inode->i_count) > 1)))
                 goto out;
 
+        error = -ENOMEM;
+        new_fl = locks_alloc_lock();
+        if (new_fl == NULL)
+                goto out;
+
         /*
          * At this point, we know that if there is an exclusive
          * lease on this file, then we hold it on this filp
@@ -1405,18 +1416,15 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
         if (!leases_enable)
                 goto out;
 
-        error = -ENOMEM;
-        fl = locks_alloc_lock();
-        if (fl == NULL)
-                goto out;
-
-        locks_copy_lock(fl, lease);
+        locks_copy_lock(new_fl, lease);
+        locks_insert_lock(before, new_fl);
 
-        locks_insert_lock(before, fl);
+        *flp = new_fl;
+        return 0;
 
-        *flp = fl;
-        error = 0;
 out:
+        if (new_fl != NULL)
+                locks_free_lock(new_fl);
         return error;
 }
 EXPORT_SYMBOL(generic_setlease);
@@ -1752,9 +1760,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
         /* Don't allow mandatory locks on files that may be memory mapped
          * and shared.
          */
-        if (IS_MANDLOCK(inode) &&
-            (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-            mapping_writably_mapped(filp->f_mapping)) {
+        if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
                 error = -EAGAIN;
                 goto out;
         }
@@ -1878,9 +1884,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
         /* Don't allow mandatory locks on files that may be memory mapped
          * and shared.
          */
-        if (IS_MANDLOCK(inode) &&
-            (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-            mapping_writably_mapped(filp->f_mapping)) {
+        if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
                 error = -EAGAIN;
                 goto out;
         }
@@ -2062,138 +2066,114 @@ int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
 
 EXPORT_SYMBOL_GPL(vfs_cancel_lock);
 
-static void lock_get_status(char* out, struct file_lock *fl, int id, char *pfx)
+#ifdef CONFIG_PROC_FS
+#include <linux/seq_file.h>
+
+static void lock_get_status(struct seq_file *f, struct file_lock *fl,
+                                                        int id, char *pfx)
 {
         struct inode *inode = NULL;
 
         if (fl->fl_file != NULL)
                 inode = fl->fl_file->f_path.dentry->d_inode;
 
-        out += sprintf(out, "%d:%s ", id, pfx);
+        seq_printf(f, "%d:%s ", id, pfx);
         if (IS_POSIX(fl)) {
-                out += sprintf(out, "%6s %s ",
+                seq_printf(f, "%6s %s ",
                              (fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ",
                              (inode == NULL) ? "*NOINODE*" :
-                             (IS_MANDLOCK(inode) &&
-                              (inode->i_mode & (S_IXGRP | S_ISGID)) == S_ISGID) ?
-                             "MANDATORY" : "ADVISORY ");
+                             mandatory_lock(inode) ? "MANDATORY" : "ADVISORY ");
         } else if (IS_FLOCK(fl)) {
                 if (fl->fl_type & LOCK_MAND) {
-                        out += sprintf(out, "FLOCK  MSNFS     ");
+                        seq_printf(f, "FLOCK  MSNFS     ");
                 } else {
-                        out += sprintf(out, "FLOCK  ADVISORY  ");
+                        seq_printf(f, "FLOCK  ADVISORY  ");
                 }
         } else if (IS_LEASE(fl)) {
-                out += sprintf(out, "LEASE  ");
+                seq_printf(f, "LEASE  ");
                 if (fl->fl_type & F_INPROGRESS)
-                        out += sprintf(out, "BREAKING  ");
+                        seq_printf(f, "BREAKING  ");
                 else if (fl->fl_file)
-                        out += sprintf(out, "ACTIVE    ");
+                        seq_printf(f, "ACTIVE    ");
                 else
-                        out += sprintf(out, "BREAKER   ");
+                        seq_printf(f, "BREAKER   ");
         } else {
-                out += sprintf(out, "UNKNOWN UNKNOWN  ");
+                seq_printf(f, "UNKNOWN UNKNOWN  ");
         }
         if (fl->fl_type & LOCK_MAND) {
-                out += sprintf(out, "%s ",
+                seq_printf(f, "%s ",
                                (fl->fl_type & LOCK_READ)
                                ? (fl->fl_type & LOCK_WRITE) ? "RW   " : "READ "
                                : (fl->fl_type & LOCK_WRITE) ? "WRITE" : "NONE ");
         } else {
-                out += sprintf(out, "%s ",
+                seq_printf(f, "%s ",
                                (fl->fl_type & F_INPROGRESS)
                                ? (fl->fl_type & F_UNLCK) ? "UNLCK" : "READ "
                                : (fl->fl_type & F_WRLCK) ? "WRITE" : "READ ");
         }
         if (inode) {
 #ifdef WE_CAN_BREAK_LSLK_NOW
-                out += sprintf(out, "%d %s:%ld ", fl->fl_pid,
+                seq_printf(f, "%d %s:%ld ", fl->fl_pid,
                                 inode->i_sb->s_id, inode->i_ino);
 #else
                 /* userspace relies on this representation of dev_t ;-( */
-                out += sprintf(out, "%d %02x:%02x:%ld ", fl->fl_pid,
+                seq_printf(f, "%d %02x:%02x:%ld ", fl->fl_pid,
                                 MAJOR(inode->i_sb->s_dev),
                                 MINOR(inode->i_sb->s_dev), inode->i_ino);
 #endif
         } else {
-                out += sprintf(out, "%d <none>:0 ", fl->fl_pid);
+                seq_printf(f, "%d <none>:0 ", fl->fl_pid);
         }
         if (IS_POSIX(fl)) {
                 if (fl->fl_end == OFFSET_MAX)
-                        out += sprintf(out, "%Ld EOF\n", fl->fl_start);
+                        seq_printf(f, "%Ld EOF\n", fl->fl_start);
                 else
-                        out += sprintf(out, "%Ld %Ld\n", fl->fl_start,
-                                        fl->fl_end);
+                        seq_printf(f, "%Ld %Ld\n", fl->fl_start, fl->fl_end);
         } else {
-                out += sprintf(out, "0 EOF\n");
+                seq_printf(f, "0 EOF\n");
         }
 }
 
-static void move_lock_status(char **p, off_t* pos, off_t offset)
+static int locks_show(struct seq_file *f, void *v)
 {
-        int len;
-        len = strlen(*p);
-        if(*pos >= offset) {
-                /* the complete line is valid */
-                *p += len;
-                *pos += len;
-                return;
-        }
-        if(*pos+len > offset) {
-                /* use the second part of the line */
-                int i = offset-*pos;
-                memmove(*p,*p+i,len-i);
-                *p += len-i;
-                *pos += len;
-                return;
-        }
-        /* discard the complete line */
-        *pos += len;
+        struct file_lock *fl, *bfl;
+
+        fl = list_entry(v, struct file_lock, fl_link);
+
+        lock_get_status(f, fl, (long)f->private, "");
+
+        list_for_each_entry(bfl, &fl->fl_block, fl_block)
+                lock_get_status(f, bfl, (long)f->private, " ->");
+
+        f->private++;
+        return 0;
 }
 
-/**
- *      get_locks_status        -       reports lock usage in /proc/locks
- *      @buffer: address in userspace to write into
- *      @start: ?
- *      @offset: how far we are through the buffer
- *      @length: how much to read
- */
+static void *locks_start(struct seq_file *f, loff_t *pos)
+{
+        lock_kernel();
+        f->private = (void *)1;
+        return seq_list_start(&file_lock_list, *pos);
+}
 
-int get_locks_status(char *buffer, char **start, off_t offset, int length)
+static void *locks_next(struct seq_file *f, void *v, loff_t *pos)
 {
-        struct list_head *tmp;
-        char *q = buffer;
-        off_t pos = 0;
-        int i = 0;
+        return seq_list_next(v, &file_lock_list, pos);
+}
 
-        lock_kernel();
-        list_for_each(tmp, &file_lock_list) {
-                struct list_head *btmp;
-                struct file_lock *fl = list_entry(tmp, struct file_lock, fl_link);
-                lock_get_status(q, fl, ++i, "");
-                move_lock_status(&q, &pos, offset);
-
-                if(pos >= offset+length)
-                        goto done;
-
-                list_for_each(btmp, &fl->fl_block) {
-                        struct file_lock *bfl = list_entry(btmp,
-                                        struct file_lock, fl_block);
-                        lock_get_status(q, bfl, i, " ->");
-                        move_lock_status(&q, &pos, offset);
-
-                        if(pos >= offset+length)
-                                goto done;
-                }
-        }
-done:
+static void locks_stop(struct seq_file *f, void *v)
+{
         unlock_kernel();
-        *start = buffer;
-        if(q-buffer < length)
-                return (q-buffer);
-        return length;
 }
 
+struct seq_operations locks_seq_operations = {
+        .start  = locks_start,
+        .next   = locks_next,
+        .stop   = locks_stop,
+        .show   = locks_show,
+};
+#endif
+
 /**
  *      lock_may_read - checks that the region is free of locks
  *      @inode: the inode that is being read