[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem

This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 41 insertions, 41 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 300eae088d5f..0a8f073435af 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -438,7 +438,7 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
         struct dentry * result;
         struct inode *dir = parent->d_inode;
 
-        down(&dir->i_sem);
+        mutex_lock(&dir->i_mutex);
         /*
          * First re-do the cached lookup just in case it was created
          * while we waited for the directory semaphore..
@@ -464,7 +464,7 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
                         else
                                 result = dentry;
                 }
-                up(&dir->i_sem);
+                mutex_unlock(&dir->i_mutex);
                 return result;
         }
 
@@ -472,7 +472,7 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
          * Uhhuh! Nasty case: the cache was re-populated while
          * we waited on the semaphore. Need to revalidate.
          */
-        up(&dir->i_sem);
+        mutex_unlock(&dir->i_mutex);
         if (result->d_op && result->d_op->d_revalidate) {
                 if (!result->d_op->d_revalidate(result, nd) && !d_invalidate(result)) {
                         dput(result);
@@ -1366,7 +1366,7 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
         struct dentry *p;
 
         if (p1 == p2) {
-                down(&p1->d_inode->i_sem);
+                mutex_lock(&p1->d_inode->i_mutex);
                 return NULL;
         }
 
@@ -1374,30 +1374,30 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 
         for (p = p1; p->d_parent != p; p = p->d_parent) {
                 if (p->d_parent == p2) {
-                        down(&p2->d_inode->i_sem);
-                        down(&p1->d_inode->i_sem);
+                        mutex_lock(&p2->d_inode->i_mutex);
+                        mutex_lock(&p1->d_inode->i_mutex);
                         return p;
                 }
         }
 
         for (p = p2; p->d_parent != p; p = p->d_parent) {
                 if (p->d_parent == p1) {
-                        down(&p1->d_inode->i_sem);
-                        down(&p2->d_inode->i_sem);
+                        mutex_lock(&p1->d_inode->i_mutex);
+                        mutex_lock(&p2->d_inode->i_mutex);
                         return p;
                 }
         }
 
-        down(&p1->d_inode->i_sem);
-        down(&p2->d_inode->i_sem);
+        mutex_lock(&p1->d_inode->i_mutex);
+        mutex_lock(&p2->d_inode->i_mutex);
         return NULL;
 }
 
 void unlock_rename(struct dentry *p1, struct dentry *p2)
 {
-        up(&p1->d_inode->i_sem);
+        mutex_unlock(&p1->d_inode->i_mutex);
         if (p1 != p2) {
-                up(&p2->d_inode->i_sem);
+                mutex_unlock(&p2->d_inode->i_mutex);
                 up(&p1->d_inode->i_sb->s_vfs_rename_sem);
         }
 }
@@ -1563,14 +1563,14 @@ int open_namei(const char * pathname, int flag, int mode, struct nameidata *nd)
 
         dir = nd->dentry;
         nd->flags &= ~LOOKUP_PARENT;
-        down(&dir->d_inode->i_sem);
+        mutex_lock(&dir->d_inode->i_mutex);
         path.dentry = lookup_hash(nd);
         path.mnt = nd->mnt;
 
 do_last:
         error = PTR_ERR(path.dentry);
         if (IS_ERR(path.dentry)) {
-                up(&dir->d_inode->i_sem);
+                mutex_unlock(&dir->d_inode->i_mutex);
                 goto exit;
         }
 
@@ -1579,7 +1579,7 @@ do_last:
                 if (!IS_POSIXACL(dir->d_inode))
                         mode &= ~current->fs->umask;
                 error = vfs_create(dir->d_inode, path.dentry, mode, nd);
-                up(&dir->d_inode->i_sem);
+                mutex_unlock(&dir->d_inode->i_mutex);
                 dput(nd->dentry);
                 nd->dentry = path.dentry;
                 if (error)
@@ -1593,7 +1593,7 @@ do_last:
         /*
          * It already exists.
          */
-        up(&dir->d_inode->i_sem);
+        mutex_unlock(&dir->d_inode->i_mutex);
 
         error = -EEXIST;
         if (flag & O_EXCL)
@@ -1665,7 +1665,7 @@ do_link:
                 goto exit;
         }
         dir = nd->dentry;
-        down(&dir->d_inode->i_sem);
+        mutex_lock(&dir->d_inode->i_mutex);
         path.dentry = lookup_hash(nd);
         path.mnt = nd->mnt;
         __putname(nd->last.name);
@@ -1680,13 +1680,13 @@ do_link:
  * Simple function to lookup and return a dentry and create it
  * if it doesn't exist.  Is SMP-safe.
  *
- * Returns with nd->dentry->d_inode->i_sem locked.
+ * Returns with nd->dentry->d_inode->i_mutex locked.
  */
 struct dentry *lookup_create(struct nameidata *nd, int is_dir)
 {
         struct dentry *dentry = ERR_PTR(-EEXIST);
 
-        down(&nd->dentry->d_inode->i_sem);
+        mutex_lock(&nd->dentry->d_inode->i_mutex);
         /*
          * Yucky last component or no last component at all?
          * (foo/., foo/.., /////)
@@ -1784,7 +1784,7 @@ asmlinkage long sys_mknod(const char __user * filename, int mode, unsigned dev)
                 }
                 dput(dentry);
         }
-        up(&nd.dentry->d_inode->i_sem);
+        mutex_unlock(&nd.dentry->d_inode->i_mutex);
         path_release(&nd);
 out:
         putname(tmp);
@@ -1836,7 +1836,7 @@ asmlinkage long sys_mkdir(const char __user * pathname, int mode)
                         error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
                         dput(dentry);
                 }
-                up(&nd.dentry->d_inode->i_sem);
+                mutex_unlock(&nd.dentry->d_inode->i_mutex);
                 path_release(&nd);
 out:
                 putname(tmp);
@@ -1885,7 +1885,7 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry)
 
         DQUOT_INIT(dir);
 
-        down(&dentry->d_inode->i_sem);
+        mutex_lock(&dentry->d_inode->i_mutex);
         dentry_unhash(dentry);
         if (d_mountpoint(dentry))
                 error = -EBUSY;
@@ -1897,7 +1897,7 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry)
                                 dentry->d_inode->i_flags |= S_DEAD;
                 }
         }
-        up(&dentry->d_inode->i_sem);
+        mutex_unlock(&dentry->d_inode->i_mutex);
         if (!error) {
                 d_delete(dentry);
         }
@@ -1932,14 +1932,14 @@ asmlinkage long sys_rmdir(const char __user * pathname)
                         error = -EBUSY;
                         goto exit1;
         }
-        down(&nd.dentry->d_inode->i_sem);
+        mutex_lock(&nd.dentry->d_inode->i_mutex);
         dentry = lookup_hash(&nd);
         error = PTR_ERR(dentry);
         if (!IS_ERR(dentry)) {
                 error = vfs_rmdir(nd.dentry->d_inode, dentry);
                 dput(dentry);
         }
-        up(&nd.dentry->d_inode->i_sem);
+        mutex_unlock(&nd.dentry->d_inode->i_mutex);
 exit1:
         path_release(&nd);
 exit:
@@ -1959,7 +1959,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
 
         DQUOT_INIT(dir);
 
-        down(&dentry->d_inode->i_sem);
+        mutex_lock(&dentry->d_inode->i_mutex);
         if (d_mountpoint(dentry))
                 error = -EBUSY;
         else {
@@ -1967,7 +1967,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
                 if (!error)
                         error = dir->i_op->unlink(dir, dentry);
         }
-        up(&dentry->d_inode->i_sem);
+        mutex_unlock(&dentry->d_inode->i_mutex);
 
         /* We don't d_delete() NFS sillyrenamed files--they still exist. */
         if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) {
@@ -1979,7 +1979,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
 
 /*
  * Make sure that the actual truncation of the file will occur outside its
- * directory's i_sem.  Truncate can take a long time if there is a lot of
+ * directory's i_mutex.  Truncate can take a long time if there is a lot of
  * writeout happening, and we don't want to prevent access to the directory
  * while waiting on the I/O.
  */
@@ -2001,7 +2001,7 @@ asmlinkage long sys_unlink(const char __user * pathname)
         error = -EISDIR;
         if (nd.last_type != LAST_NORM)
                 goto exit1;
-        down(&nd.dentry->d_inode->i_sem);
+        mutex_lock(&nd.dentry->d_inode->i_mutex);
         dentry = lookup_hash(&nd);
         error = PTR_ERR(dentry);
         if (!IS_ERR(dentry)) {
@@ -2015,7 +2015,7 @@ asmlinkage long sys_unlink(const char __user * pathname)
         exit2:
                 dput(dentry);
         }
-        up(&nd.dentry->d_inode->i_sem);
+        mutex_unlock(&nd.dentry->d_inode->i_mutex);
         if (inode)
                 iput(inode);    /* truncate the inode here */
 exit1:
@@ -2075,7 +2075,7 @@ asmlinkage long sys_symlink(const char __user * oldname, const char __user * new
                         error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
                         dput(dentry);
                 }
-                up(&nd.dentry->d_inode->i_sem);
+                mutex_unlock(&nd.dentry->d_inode->i_mutex);
                 path_release(&nd);
 out:
                 putname(to);
@@ -2113,10 +2113,10 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
         if (error)
                 return error;
 
-        down(&old_dentry->d_inode->i_sem);
+        mutex_lock(&old_dentry->d_inode->i_mutex);
         DQUOT_INIT(dir);
         error = dir->i_op->link(old_dentry, dir, new_dentry);
-        up(&old_dentry->d_inode->i_sem);
+        mutex_unlock(&old_dentry->d_inode->i_mutex);
         if (!error)
                 fsnotify_create(dir, new_dentry->d_name.name);
         return error;
@@ -2157,7 +2157,7 @@ asmlinkage long sys_link(const char __user * oldname, const char __user * newnam
                 error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
                 dput(new_dentry);
         }
-        up(&nd.dentry->d_inode->i_sem);
+        mutex_unlock(&nd.dentry->d_inode->i_mutex);
 out_release:
         path_release(&nd);
 out:
@@ -2178,7 +2178,7 @@ exit:
  *         sb->s_vfs_rename_sem. We might be more accurate, but that's another
  *         story.
  *      c) we have to lock _three_ objects - parents and victim (if it exists).
- *         And that - after we got ->i_sem on parents (until then we don't know
+ *         And that - after we got ->i_mutex on parents (until then we don't know
  *         whether the target exists).  Solution: try to be smart with locking
  *         order for inodes.  We rely on the fact that tree topology may change
  *         only under ->s_vfs_rename_sem _and_ that parent of the object we
@@ -2195,9 +2195,9 @@ exit:
  *         stuff into VFS), but the former is not going away. Solution: the same
  *         trick as in rmdir().
  *      e) conversion from fhandle to dentry may come in the wrong moment - when
- *         we are removing the target. Solution: we will have to grab ->i_sem
+ *         we are removing the target. Solution: we will have to grab ->i_mutex
  *         in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on
- *         ->i_sem on parents, which works but leads to some truely excessive
+ *         ->i_mutex on parents, which works but leads to some truely excessive
  *         locking].
  */
 static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
@@ -2222,7 +2222,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
 
         target = new_dentry->d_inode;
         if (target) {
-                down(&target->i_sem);
+                mutex_lock(&target->i_mutex);
                 dentry_unhash(new_dentry);
         }
         if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
@@ -2232,7 +2232,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
         if (target) {
                 if (!error)
                         target->i_flags |= S_DEAD;
-                up(&target->i_sem);
+                mutex_unlock(&target->i_mutex);
                 if (d_unhashed(new_dentry))
                         d_rehash(new_dentry);
                 dput(new_dentry);
@@ -2255,7 +2255,7 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
         dget(new_dentry);
         target = new_dentry->d_inode;
         if (target)
-                down(&target->i_sem);
+                mutex_lock(&target->i_mutex);
         if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
                 error = -EBUSY;
         else
@@ -2266,7 +2266,7 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
                         d_move(old_dentry, new_dentry);
         }
         if (target)
-                up(&target->i_sem);
+                mutex_unlock(&target->i_mutex);
         dput(new_dentry);
         return error;
 }