]> nv-tegra.nvidia Code Review - linux-2.6.git/commitdiff
ext4: convert to new aops
authorNick Piggin <npiggin@suse.de>
Tue, 16 Oct 2007 08:25:05 +0000 (01:25 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 16 Oct 2007 16:42:55 +0000 (09:42 -0700)
Convert ext4 to use write_begin()/write_end() methods.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Dmitriy Monakhov <dmonakhov@sw.ru>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ext4/inode.c

index a4848e04a5edf1cb4b48aa02ea58eb5b55585adc..0df2b1e06d0b75be46a211b24085ea6485c7b7a6 100644 (file)
@@ -1146,34 +1146,50 @@ static int do_journal_get_write_access(handle_t *handle,
        return ext4_journal_get_write_access(handle, bh);
 }
 
-static int ext4_prepare_write(struct file *file, struct page *page,
-                             unsigned from, unsigned to)
+static int ext4_write_begin(struct file *file, struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned flags,
+                               struct page **pagep, void **fsdata)
 {
-       struct inode *inode = page->mapping->host;
+       struct inode *inode = mapping->host;
        int ret, needed_blocks = ext4_writepage_trans_blocks(inode);
        handle_t *handle;
        int retries = 0;
+       struct page *page;
+       pgoff_t index;
+       unsigned from, to;
+
+       index = pos >> PAGE_CACHE_SHIFT;
+       from = pos & (PAGE_CACHE_SIZE - 1);
+       to = from + len;
 
 retry:
-       handle = ext4_journal_start(inode, needed_blocks);
-       if (IS_ERR(handle)) {
-               ret = PTR_ERR(handle);
-               goto out;
+       page = __grab_cache_page(mapping, index);
+       if (!page)
+               return -ENOMEM;
+       *pagep = page;
+
+       handle = ext4_journal_start(inode, needed_blocks);
+       if (IS_ERR(handle)) {
+               unlock_page(page);
+               page_cache_release(page);
+               ret = PTR_ERR(handle);
+               goto out;
        }
-       if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
-               ret = nobh_prepare_write(page, from, to, ext4_get_block);
-       else
-               ret = block_prepare_write(page, from, to, ext4_get_block);
-       if (ret)
-               goto prepare_write_failed;
 
-       if (ext4_should_journal_data(inode)) {
+       ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+                                                       ext4_get_block);
+
+       if (!ret && ext4_should_journal_data(inode)) {
                ret = walk_page_buffers(handle, page_buffers(page),
                                from, to, NULL, do_journal_get_write_access);
        }
-prepare_write_failed:
-       if (ret)
+
+       if (ret) {
                ext4_journal_stop(handle);
+               unlock_page(page);
+               page_cache_release(page);
+       }
+
        if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
                goto retry;
 out:
@@ -1185,12 +1201,12 @@ int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
        int err = jbd2_journal_dirty_data(handle, bh);
        if (err)
                ext4_journal_abort_handle(__FUNCTION__, __FUNCTION__,
-                                               bh, handle,err);
+                                               bh, handle, err);
        return err;
 }
 
-/* For commit_write() in data=journal mode */
-static int commit_write_fn(handle_t *handle, struct buffer_head *bh)
+/* For write_end() in data=journal mode */
+static int write_end_fn(handle_t *handle, struct buffer_head *bh)
 {
        if (!buffer_mapped(bh) || buffer_freed(bh))
                return 0;
@@ -1198,6 +1214,29 @@ static int commit_write_fn(handle_t *handle, struct buffer_head *bh)
        return ext4_journal_dirty_metadata(handle, bh);
 }
 
+/*
+ * Generic write_end handler for ordered and writeback ext4 journal modes.
+ * We can't use generic_write_end, because that unlocks the page and we need to
+ * unlock the page after ext4_journal_stop, but ext4_journal_stop must run
+ * after block_write_end.
+ */
+static int ext4_generic_write_end(struct file *file,
+                               struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata)
+{
+       struct inode *inode = file->f_mapping->host;
+
+       copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
+
+       if (pos+copied > inode->i_size) {
+               i_size_write(inode, pos+copied);
+               mark_inode_dirty(inode);
+       }
+
+       return copied;
+}
+
 /*
  * We need to pick up the new inode size which generic_commit_write gave us
  * `file' can be NULL - eg, when called from page_symlink().
@@ -1205,78 +1244,101 @@ static int commit_write_fn(handle_t *handle, struct buffer_head *bh)
  * ext4 never places buffers on inode->i_mapping->private_list.  metadata
  * buffers are managed internally.
  */
-static int ext4_ordered_commit_write(struct file *file, struct page *page,
-                            unsigned from, unsigned to)
+static int ext4_ordered_write_end(struct file *file,
+                               struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata)
 {
        handle_t *handle = ext4_journal_current_handle();
-       struct inode *inode = page->mapping->host;
+       struct inode *inode = file->f_mapping->host;
+       unsigned from, to;
        int ret = 0, ret2;
 
+       from = pos & (PAGE_CACHE_SIZE - 1);
+       to = from + len;
+
        ret = walk_page_buffers(handle, page_buffers(page),
                from, to, NULL, ext4_journal_dirty_data);
 
        if (ret == 0) {
                /*
-                * generic_commit_write() will run mark_inode_dirty() if i_size
+                * generic_write_end() will run mark_inode_dirty() if i_size
                 * changes.  So let's piggyback the i_disksize mark_inode_dirty
                 * into that.
                 */
                loff_t new_i_size;
 
-               new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+               new_i_size = pos + copied;
                if (new_i_size > EXT4_I(inode)->i_disksize)
                        EXT4_I(inode)->i_disksize = new_i_size;
-               ret = generic_commit_write(file, page, from, to);
+               copied = ext4_generic_write_end(file, mapping, pos, len, copied,
+                                                       page, fsdata);
+               if (copied < 0)
+                       ret = copied;
        }
        ret2 = ext4_journal_stop(handle);
        if (!ret)
                ret = ret2;
-       return ret;
+       unlock_page(page);
+       page_cache_release(page);
+
+       return ret ? ret : copied;
 }
 
-static int ext4_writeback_commit_write(struct file *file, struct page *page,
-                            unsigned from, unsigned to)
+static int ext4_writeback_write_end(struct file *file,
+                               struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata)
 {
        handle_t *handle = ext4_journal_current_handle();
-       struct inode *inode = page->mapping->host;
+       struct inode *inode = file->f_mapping->host;
        int ret = 0, ret2;
        loff_t new_i_size;
 
-       new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+       new_i_size = pos + copied;
        if (new_i_size > EXT4_I(inode)->i_disksize)
                EXT4_I(inode)->i_disksize = new_i_size;
 
-       if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
-               ret = nobh_commit_write(file, page, from, to);
-       else
-               ret = generic_commit_write(file, page, from, to);
+       copied = ext4_generic_write_end(file, mapping, pos, len, copied,
+                                                       page, fsdata);
+       if (copied < 0)
+               ret = copied;
 
        ret2 = ext4_journal_stop(handle);
        if (!ret)
                ret = ret2;
-       return ret;
+       unlock_page(page);
+       page_cache_release(page);
+
+       return ret ? ret : copied;
 }
 
-static int ext4_journalled_commit_write(struct file *file,
-                       struct page *page, unsigned from, unsigned to)
+static int ext4_journalled_write_end(struct file *file,
+                               struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata)
 {
        handle_t *handle = ext4_journal_current_handle();
-       struct inode *inode = page->mapping->host;
+       struct inode *inode = mapping->host;
        int ret = 0, ret2;
        int partial = 0;
-       loff_t pos;
+       unsigned from, to;
 
-       /*
-        * Here we duplicate the generic_commit_write() functionality
-        */
-       pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+       from = pos & (PAGE_CACHE_SIZE - 1);
+       to = from + len;
+
+       if (copied < len) {
+               if (!PageUptodate(page))
+                       copied = 0;
+               page_zero_new_buffers(page, from+copied, to);
+       }
 
        ret = walk_page_buffers(handle, page_buffers(page), from,
-                               to, &partial, commit_write_fn);
+                               to, &partial, write_end_fn);
        if (!partial)
                SetPageUptodate(page);
-       if (pos > inode->i_size)
-               i_size_write(inode, pos);
+       if (pos+copied > inode->i_size)
+               i_size_write(inode, pos+copied);
        EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
        if (inode->i_size > EXT4_I(inode)->i_disksize) {
                EXT4_I(inode)->i_disksize = inode->i_size;
@@ -1284,10 +1346,14 @@ static int ext4_journalled_commit_write(struct file *file,
                if (!ret)
                        ret = ret2;
        }
+
        ret2 = ext4_journal_stop(handle);
        if (!ret)
                ret = ret2;
-       return ret;
+       unlock_page(page);
+       page_cache_release(page);
+
+       return ret ? ret : copied;
 }
 
 /*
@@ -1545,7 +1611,7 @@ static int ext4_journalled_writepage(struct page *page,
                        PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
 
                err = walk_page_buffers(handle, page_buffers(page), 0,
-                               PAGE_CACHE_SIZE, NULL, commit_write_fn);
+                               PAGE_CACHE_SIZE, NULL, write_end_fn);
                if (ret == 0)
                        ret = err;
                EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
@@ -1705,8 +1771,8 @@ static const struct address_space_operations ext4_ordered_aops = {
        .readpages      = ext4_readpages,
        .writepage      = ext4_ordered_writepage,
        .sync_page      = block_sync_page,
-       .prepare_write  = ext4_prepare_write,
-       .commit_write   = ext4_ordered_commit_write,
+       .write_begin    = ext4_write_begin,
+       .write_end      = ext4_ordered_write_end,
        .bmap           = ext4_bmap,
        .invalidatepage = ext4_invalidatepage,
        .releasepage    = ext4_releasepage,
@@ -1719,8 +1785,8 @@ static const struct address_space_operations ext4_writeback_aops = {
        .readpages      = ext4_readpages,
        .writepage      = ext4_writeback_writepage,
        .sync_page      = block_sync_page,
-       .prepare_write  = ext4_prepare_write,
-       .commit_write   = ext4_writeback_commit_write,
+       .write_begin    = ext4_write_begin,
+       .write_end      = ext4_writeback_write_end,
        .bmap           = ext4_bmap,
        .invalidatepage = ext4_invalidatepage,
        .releasepage    = ext4_releasepage,
@@ -1733,8 +1799,8 @@ static const struct address_space_operations ext4_journalled_aops = {
        .readpages      = ext4_readpages,
        .writepage      = ext4_journalled_writepage,
        .sync_page      = block_sync_page,
-       .prepare_write  = ext4_prepare_write,
-       .commit_write   = ext4_journalled_commit_write,
+       .write_begin    = ext4_write_begin,
+       .write_end      = ext4_journalled_write_end,
        .set_page_dirty = ext4_journalled_set_page_dirty,
        .bmap           = ext4_bmap,
        .invalidatepage = ext4_invalidatepage,