ext4: Simplify delalloc implementation by removing mpd.get_block

This parameter was always set to ext4_da_get_block_write().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 58 insertions, 67 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index cd0399db0ef1..924ba8afc227 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1705,7 +1705,6 @@ struct mpage_da_data {
         struct inode *inode;
         struct buffer_head lbh;                 /* extent of blocks */
         unsigned long first_page, next_page;    /* extent of pages */
-        get_block_t *get_block;
         struct writeback_control *wbc;
         int io_done;
         int pages_written;
@@ -1719,7 +1718,6 @@ struct mpage_da_data {
  * @mpd->inode: inode
  * @mpd->first_page: first page of the extent
  * @mpd->next_page: page after the last page of the extent
- * @mpd->get_block: the filesystem's block mapper function
  *
  * By the time mpage_da_submit_io() is called we expect all blocks
  * to be allocated. this may be wrong if allocation failed.
@@ -1929,16 +1927,60 @@ static void ext4_print_free_blocks(struct inode *inode)
         return;
 }
 
+#define         EXT4_DELALLOC_RSVED     1
+static int ext4_da_get_block_write(struct inode *inode, sector_t iblock,
+                                   struct buffer_head *bh_result, int create)
+{
+        int ret;
+        unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+        loff_t disksize = EXT4_I(inode)->i_disksize;
+        handle_t *handle = NULL;
+
+        handle = ext4_journal_current_handle();
+        BUG_ON(!handle);
+        ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
+                                   bh_result, create, 0, EXT4_DELALLOC_RSVED);
+        if (ret <= 0)
+                return ret;
+
+        bh_result->b_size = (ret << inode->i_blkbits);
+
+        if (ext4_should_order_data(inode)) {
+                int retval;
+                retval = ext4_jbd2_file_inode(handle, inode);
+                if (retval)
+                        /*
+                         * Failed to add inode for ordered mode. Don't
+                         * update file size
+                         */
+                        return retval;
+        }
+
+        /*
+         * Update on-disk size along with block allocation we don't
+         * use 'extend_disksize' as size may change within already
+         * allocated block -bzzz
+         */
+        disksize = ((loff_t) iblock + ret) << inode->i_blkbits;
+        if (disksize > i_size_read(inode))
+                disksize = i_size_read(inode);
+        if (disksize > EXT4_I(inode)->i_disksize) {
+                ext4_update_i_disksize(inode, disksize);
+                ret = ext4_mark_inode_dirty(handle, inode);
+                return ret;
+        }
+        return 0;
+}
+
 /*
  * mpage_da_map_blocks - go through given space
  *
  * @mpd->lbh - bh describing space
- * @mpd->get_block - the filesystem's block mapper function
  *
  * The function skips space we know is already mapped to disk blocks.
  *
  */
-static int  mpage_da_map_blocks(struct mpage_da_data *mpd)
+static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 {
         int err = 0;
         struct buffer_head new;
@@ -1960,30 +2002,29 @@ static int  mpage_da_map_blocks(struct mpage_da_data *mpd)
          */
         if (!new.b_size)
                 return 0;
-        err = mpd->get_block(mpd->inode, next, &new, 1);
-        if (err) {
 
-                /* If get block returns with error
-                 * we simply return. Later writepage
-                 * will redirty the page and writepages
-                 * will find the dirty page again
+        err = ext4_da_get_block_write(mpd->inode, next, &new, 1);
+        if (err) {
+                /*
+                 * If get block returns with error we simply
+                 * return. Later writepage will redirty the page and
+                 * writepages will find the dirty page again
                  */
                 if (err == -EAGAIN)
                         return 0;
 
                 if (err == -ENOSPC &&
-                                ext4_count_free_blocks(mpd->inode->i_sb)) {
+                    ext4_count_free_blocks(mpd->inode->i_sb)) {
                         mpd->retval = err;
                         return 0;
                 }
 
                 /*
-                 * get block failure will cause us
-                 * to loop in writepages. Because
-                 * a_ops->writepage won't be able to
-                 * make progress. The page will be redirtied
-                 * by writepage and writepages will again
-                 * try to write the same.
+                 * get block failure will cause us to loop in
+                 * writepages, because a_ops->writepage won't be able
+                 * to make progress. The page will be redirtied by
+                 * writepage and writepages will again try to write
+                 * the same.
                  */
                 printk(KERN_EMERG "%s block allocation failed for inode %lu "
                                   "at logical offset %llu with max blocks "
@@ -2212,7 +2253,6 @@ static int __mpage_da_writepage(struct page *page,
  *
  * @mapping: address space structure to write
  * @wbc: subtract the number of written pages from *@wbc->nr_to_write
- * @get_block: the filesystem's block mapper function.
  *
  * This is a library function, which implements the writepages()
  * address_space_operation.
@@ -2223,9 +2263,6 @@ static int mpage_da_writepages(struct address_space *mapping,
 {
         int ret;
 
-        if (!mpd->get_block)
-                return generic_writepages(mapping, wbc);
-
         mpd->lbh.b_size = 0;
         mpd->lbh.b_state = 0;
         mpd->lbh.b_blocknr = 0;
@@ -2289,51 +2326,6 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
 
         return ret;
 }
-#define         EXT4_DELALLOC_RSVED     1
-static int ext4_da_get_block_write(struct inode *inode, sector_t iblock,
-                                   struct buffer_head *bh_result, int create)
-{
-        int ret;
-        unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
-        loff_t disksize = EXT4_I(inode)->i_disksize;
-        handle_t *handle = NULL;
-
-        handle = ext4_journal_current_handle();
-        BUG_ON(!handle);
-        ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
-                        bh_result, create, 0, EXT4_DELALLOC_RSVED);
-        if (ret > 0) {
-
-                bh_result->b_size = (ret << inode->i_blkbits);
-
-                if (ext4_should_order_data(inode)) {
-                        int retval;
-                        retval = ext4_jbd2_file_inode(handle, inode);
-                        if (retval)
-                                /*
-                                 * Failed to add inode for ordered
-                                 * mode. Don't update file size
-                                 */
-                                return retval;
-                }
-
-                /*
-                 * Update on-disk size along with block allocation
-                 * we don't use 'extend_disksize' as size may change
-                 * within already allocated block -bzzz
-                 */
-                disksize = ((loff_t) iblock + ret) << inode->i_blkbits;
-                if (disksize > i_size_read(inode))
-                        disksize = i_size_read(inode);
-                if (disksize > EXT4_I(inode)->i_disksize) {
-                        ext4_update_i_disksize(inode, disksize);
-                        ret = ext4_mark_inode_dirty(handle, inode);
-                        return ret;
-                }
-                ret = 0;
-        }
-        return ret;
-}
 
 static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh)
 {
@@ -2584,7 +2576,6 @@ retry:
                         dump_stack();
                         goto out_writepages;
                 }
-                mpd.get_block = ext4_da_get_block_write;
                 ret = mpage_da_writepages(mapping, wbc, &mpd);
 
                 ext4_journal_stop(handle);