]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - mm/filemap.c
Merge master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6-omap-h63xx.git] / mm / filemap.c
index 4ef24a397684f7b9a51c70e94843f4cff35ed281..44da3d47699485004994c6af302c7406d606c569 100644 (file)
@@ -15,6 +15,7 @@
 #include <linux/compiler.h>
 #include <linux/fs.h>
 #include <linux/aio.h>
+#include <linux/capability.h>
 #include <linux/kernel_stat.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
@@ -61,7 +62,7 @@ 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 +74,9 @@ 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
@@ -93,6 +94,7 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
  *    ->private_lock           (try_to_unmap_one)
  *    ->tree_lock              (try_to_unmap_one)
  *    ->zone.lru_lock          (follow_page->mark_page_accessed)
+ *    ->zone.lru_lock          (check_pte_range->isolate_lru_page)
  *    ->private_lock           (page_remove_rmap->set_page_dirty)
  *    ->tree_lock              (page_remove_rmap->set_page_dirty)
  *    ->inode_lock             (page_remove_rmap->set_page_dirty)
@@ -276,11 +278,11 @@ 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,
-                       loff_t pos, size_t count)
+                       loff_t pos, loff_t count)
 {
        pgoff_t start = pos >> PAGE_CACHE_SHIFT;
        pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
@@ -290,9 +292,9 @@ 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);
@@ -301,13 +303,12 @@ 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.
  */
-static int sync_page_range_nolock(struct inode *inode,
-                                 struct address_space *mapping,
-                                 loff_t pos, size_t count)
+int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
+                          loff_t pos, loff_t count)
 {
        pgoff_t start = pos >> PAGE_CACHE_SHIFT;
        pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
@@ -322,6 +323,7 @@ static int sync_page_range_nolock(struct inode *inode,
                ret = wait_on_page_writeback_range(mapping, start, end);
        return ret;
 }
+EXPORT_SYMBOL(sync_page_range_nolock);
 
 /**
  * filemap_fdatawait - walk the list of under-writeback pages of the given
@@ -343,30 +345,44 @@ EXPORT_SYMBOL(filemap_fdatawait);
 
 int filemap_write_and_wait(struct address_space *mapping)
 {
-       int retval = 0;
+       int err = 0;
 
        if (mapping->nrpages) {
-               retval = filemap_fdatawrite(mapping);
-               if (retval == 0)
-                       retval = filemap_fdatawait(mapping);
+               err = filemap_fdatawrite(mapping);
+               /*
+                * Even if the above returned error, the pages may be
+                * written partially (e.g. -ENOSPC), so we wait for it.
+                * But the -EIO is special case, it may indicate the worst
+                * thing (e.g. bug) happened, so we avoid waiting for it.
+                */
+               if (err != -EIO) {
+                       int err2 = filemap_fdatawait(mapping);
+                       if (!err)
+                               err = err2;
+               }
        }
-       return retval;
+       return err;
 }
+EXPORT_SYMBOL(filemap_write_and_wait);
 
 int filemap_write_and_wait_range(struct address_space *mapping,
                                 loff_t lstart, loff_t lend)
 {
-       int retval = 0;
+       int err = 0;
 
        if (mapping->nrpages) {
-               retval = __filemap_fdatawrite_range(mapping, lstart, lend,
-                                                   WB_SYNC_ALL);
-               if (retval == 0)
-                       retval = wait_on_page_writeback_range(mapping,
-                                                   lstart >> PAGE_CACHE_SHIFT,
-                                                   lend >> PAGE_CACHE_SHIFT);
+               err = __filemap_fdatawrite_range(mapping, lstart, lend,
+                                                WB_SYNC_ALL);
+               /* See comment of filemap_write_and_wait() */
+               if (err != -EIO) {
+                       int err2 = wait_on_page_writeback_range(mapping,
+                                               lstart >> PAGE_CACHE_SHIFT,
+                                               lend >> PAGE_CACHE_SHIFT);
+                       if (!err)
+                               err = err2;
+               }
        }
-       return retval;
+       return err;
 }
 
 /*
@@ -1878,7 +1894,7 @@ 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))) {
@@ -2094,7 +2110,7 @@ __generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
        if (err)
                goto out;
 
-       inode_update_time(inode, 1);
+       file_update_time(file);
 
        /* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
        if (unlikely(file->f_flags & O_DIRECT)) {
@@ -2181,10 +2197,10 @@ 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;
@@ -2206,9 +2222,9 @@ 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;
@@ -2242,9 +2258,9 @@ 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;
@@ -2258,7 +2274,7 @@ 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