[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, 15 insertions, 15 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 478f4c74cc31..5fca2737c971 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -61,7 +61,7 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
  *      ->swap_lock             (exclusive_swap_page, others)
  *        ->mapping->tree_lock
  *
- *  ->i_sem
+ *  ->i_mutex
  *    ->i_mmap_lock             (truncate->unmap_mapping_range)
  *
  *  ->mmap_sem
@@ -73,9 +73,9 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
  *    ->lock_page               (access_process_vm)
  *
  *  ->mmap_sem
- *    ->i_sem                   (msync)
+ *    ->i_mutex                 (msync)
  *
- *  ->i_sem
+ *  ->i_mutex
  *    ->i_alloc_sem             (various)
  *
  *  ->inode_lock
@@ -276,7 +276,7 @@ static int wait_on_page_writeback_range(struct address_space *mapping,
  * integrity" operation.  It waits upon in-flight writeout before starting and
  * waiting upon new writeout.  If there was an IO error, return it.
  *
- * We need to re-take i_sem during the generic_osync_inode list walk because
+ * We need to re-take i_mutex during the generic_osync_inode list walk because
  * it is otherwise livelockable.
  */
 int sync_page_range(struct inode *inode, struct address_space *mapping,
@@ -290,9 +290,9 @@ int sync_page_range(struct inode *inode, struct address_space *mapping,
                 return 0;
         ret = filemap_fdatawrite_range(mapping, pos, pos + count - 1);
         if (ret == 0) {
-                down(&inode->i_sem);
+                mutex_lock(&inode->i_mutex);
                 ret = generic_osync_inode(inode, mapping, OSYNC_METADATA);
-                up(&inode->i_sem);
+                mutex_unlock(&inode->i_mutex);
         }
         if (ret == 0)
                 ret = wait_on_page_writeback_range(mapping, start, end);
@@ -301,7 +301,7 @@ int sync_page_range(struct inode *inode, struct address_space *mapping,
 EXPORT_SYMBOL(sync_page_range);
 
 /*
- * Note: Holding i_sem across sync_page_range_nolock is not a good idea
+ * Note: Holding i_mutex across sync_page_range_nolock is not a good idea
  * as it forces O_SYNC writers to different parts of the same file
  * to be serialised right until io completion.
  */
@@ -1892,7 +1892,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
         /*
          * Sync the fs metadata but not the minor inode changes and
          * of course not the data as we did direct DMA for the IO.
-         * i_sem is held, which protects generic_osync_inode() from
+         * i_mutex is held, which protects generic_osync_inode() from
          * livelocking.
          */
         if (written >= 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
@@ -2195,10 +2195,10 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const char __user *buf,
 
         BUG_ON(iocb->ki_pos != pos);
 
-        down(&inode->i_sem);
+        mutex_lock(&inode->i_mutex);
         ret = __generic_file_aio_write_nolock(iocb, &local_iov, 1,
                                                 &iocb->ki_pos);
-        up(&inode->i_sem);
+        mutex_unlock(&inode->i_mutex);
 
         if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
                 ssize_t err;
@@ -2220,9 +2220,9 @@ ssize_t generic_file_write(struct file *file, const char __user *buf,
         struct iovec local_iov = { .iov_base = (void __user *)buf,
                                         .iov_len = count };
 
-        down(&inode->i_sem);
+        mutex_lock(&inode->i_mutex);
         ret = __generic_file_write_nolock(file, &local_iov, 1, ppos);
-        up(&inode->i_sem);
+        mutex_unlock(&inode->i_mutex);
 
         if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
                 ssize_t err;
@@ -2256,9 +2256,9 @@ ssize_t generic_file_writev(struct file *file, const struct iovec *iov,
         struct inode *inode = mapping->host;
         ssize_t ret;
 
-        down(&inode->i_sem);
+        mutex_lock(&inode->i_mutex);
         ret = __generic_file_write_nolock(file, iov, nr_segs, ppos);
-        up(&inode->i_sem);
+        mutex_unlock(&inode->i_mutex);
 
         if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
                 int err;
@@ -2272,7 +2272,7 @@ ssize_t generic_file_writev(struct file *file, const struct iovec *iov,
 EXPORT_SYMBOL(generic_file_writev);
 
 /*
- * Called under i_sem for writes to S_ISREG files.   Returns -EIO if something
+ * Called under i_mutex for writes to S_ISREG files.   Returns -EIO if something
  * went wrong during pagecache shootdown.
  */
 static ssize_t