]> bbs.cooldavid.org Git - net-next-2.6.git/blobdiff - fs/ext4/inode.c
ext4: Convert callers of ext4_get_blocks() to use ext4_map_blocks()
[net-next-2.6.git] / fs / ext4 / inode.c
index ff2f5fd681b585f1f0000e511bff005f14eb4bcb..0b1d7c89f93fd86a9ae482417a2eab91dc3b3dd9 100644 (file)
@@ -1336,133 +1336,112 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
        return retval;
 }
 
-int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block,
-                   unsigned int max_blocks, struct buffer_head *bh,
-                   int flags)
-{
-       struct ext4_map_blocks map;
-       int ret;
-
-       map.m_lblk = block;
-       map.m_len = max_blocks;
-
-       ret = ext4_map_blocks(handle, inode, &map, flags);
-       if (ret < 0)
-               return ret;
-
-       bh->b_blocknr = map.m_pblk;
-       bh->b_size = inode->i_sb->s_blocksize * map.m_len;
-       bh->b_bdev = inode->i_sb->s_bdev;
-       bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
-       return ret;
-}
-
 /* Maximum number of blocks we map for direct IO at once. */
 #define DIO_MAX_BLOCKS 4096
 
-int ext4_get_block(struct inode *inode, sector_t iblock,
-                  struct buffer_head *bh_result, int create)
+static int _ext4_get_block(struct inode *inode, sector_t iblock,
+                          struct buffer_head *bh, int flags)
 {
        handle_t *handle = ext4_journal_current_handle();
+       struct ext4_map_blocks map;
        int ret = 0, started = 0;
-       unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
        int dio_credits;
 
-       if (create && !handle) {
+       map.m_lblk = iblock;
+       map.m_len = bh->b_size >> inode->i_blkbits;
+
+       if (flags && !handle) {
                /* Direct IO write... */
-               if (max_blocks > DIO_MAX_BLOCKS)
-                       max_blocks = DIO_MAX_BLOCKS;
-               dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
+               if (map.m_len > DIO_MAX_BLOCKS)
+                       map.m_len = DIO_MAX_BLOCKS;
+               dio_credits = ext4_chunk_trans_blocks(inode, map.m_len);
                handle = ext4_journal_start(inode, dio_credits);
                if (IS_ERR(handle)) {
                        ret = PTR_ERR(handle);
-                       goto out;
+                       return ret;
                }
                started = 1;
        }
 
-       ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
-                             create ? EXT4_GET_BLOCKS_CREATE : 0);
+       ret = ext4_map_blocks(handle, inode, &map, flags);
        if (ret > 0) {
-               bh_result->b_size = (ret << inode->i_blkbits);
+               map_bh(bh, inode->i_sb, map.m_pblk);
+               bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
+               bh->b_size = inode->i_sb->s_blocksize * map.m_len;
                ret = 0;
        }
        if (started)
                ext4_journal_stop(handle);
-out:
        return ret;
 }
 
+int ext4_get_block(struct inode *inode, sector_t iblock,
+                  struct buffer_head *bh, int create)
+{
+       return _ext4_get_block(inode, iblock, bh,
+                              create ? EXT4_GET_BLOCKS_CREATE : 0);
+}
+
 /*
  * `handle' can be NULL if create is zero
  */
 struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
                                ext4_lblk_t block, int create, int *errp)
 {
-       struct buffer_head dummy;
+       struct ext4_map_blocks map;
+       struct buffer_head *bh;
        int fatal = 0, err;
-       int flags = 0;
 
        J_ASSERT(handle != NULL || create == 0);
 
-       dummy.b_state = 0;
-       dummy.b_blocknr = -1000;
-       buffer_trace_init(&dummy.b_history);
-       if (create)
-               flags |= EXT4_GET_BLOCKS_CREATE;
-       err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags);
-       /*
-        * ext4_get_blocks() returns number of blocks mapped. 0 in
-        * case of a HOLE.
-        */
-       if (err > 0) {
-               if (err > 1)
-                       WARN_ON(1);
-               err = 0;
+       map.m_lblk = block;
+       map.m_len = 1;
+       err = ext4_map_blocks(handle, inode, &map,
+                             create ? EXT4_GET_BLOCKS_CREATE : 0);
+
+       if (err < 0)
+               *errp = err;
+       if (err <= 0)
+               return NULL;
+       *errp = 0;
+
+       bh = sb_getblk(inode->i_sb, map.m_pblk);
+       if (!bh) {
+               *errp = -EIO;
+               return NULL;
        }
-       *errp = err;
-       if (!err && buffer_mapped(&dummy)) {
-               struct buffer_head *bh;
-               bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
-               if (!bh) {
-                       *errp = -EIO;
-                       goto err;
-               }
-               if (buffer_new(&dummy)) {
-                       J_ASSERT(create != 0);
-                       J_ASSERT(handle != NULL);
+       if (map.m_flags & EXT4_MAP_NEW) {
+               J_ASSERT(create != 0);
+               J_ASSERT(handle != NULL);
 
-                       /*
-                        * Now that we do not always journal data, we should
-                        * keep in mind whether this should always journal the
-                        * new buffer as metadata.  For now, regular file
-                        * writes use ext4_get_block instead, so it's not a
-                        * problem.
-                        */
-                       lock_buffer(bh);
-                       BUFFER_TRACE(bh, "call get_create_access");
-                       fatal = ext4_journal_get_create_access(handle, bh);
-                       if (!fatal && !buffer_uptodate(bh)) {
-                               memset(bh->b_data, 0, inode->i_sb->s_blocksize);
-                               set_buffer_uptodate(bh);
-                       }
-                       unlock_buffer(bh);
-                       BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
-                       err = ext4_handle_dirty_metadata(handle, inode, bh);
-                       if (!fatal)
-                               fatal = err;
-               } else {
-                       BUFFER_TRACE(bh, "not a new buffer");
-               }
-               if (fatal) {
-                       *errp = fatal;
-                       brelse(bh);
-                       bh = NULL;
+               /*
+                * Now that we do not always journal data, we should
+                * keep in mind whether this should always journal the
+                * new buffer as metadata.  For now, regular file
+                * writes use ext4_get_block instead, so it's not a
+                * problem.
+                */
+               lock_buffer(bh);
+               BUFFER_TRACE(bh, "call get_create_access");
+               fatal = ext4_journal_get_create_access(handle, bh);
+               if (!fatal && !buffer_uptodate(bh)) {
+                       memset(bh->b_data, 0, inode->i_sb->s_blocksize);
+                       set_buffer_uptodate(bh);
                }
-               return bh;
+               unlock_buffer(bh);
+               BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+               err = ext4_handle_dirty_metadata(handle, inode, bh);
+               if (!fatal)
+                       fatal = err;
+       } else {
+               BUFFER_TRACE(bh, "not a new buffer");
        }
-err:
-       return NULL;
+       if (fatal) {
+               *errp = fatal;
+               brelse(bh);
+               bh = NULL;
+       }
+       return bh;
 }
 
 struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
@@ -2050,28 +2029,23 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd)
 /*
  * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers
  *
- * @mpd->inode - inode to walk through
- * @exbh->b_blocknr - first block on a disk
- * @exbh->b_size - amount of space in bytes
- * @logical - first logical block to start assignment with
- *
  * the function goes through all passed space and put actual disk
  * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten
  */
-static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
-                                struct buffer_head *exbh)
+static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd,
+                                struct ext4_map_blocks *map)
 {
        struct inode *inode = mpd->inode;
        struct address_space *mapping = inode->i_mapping;
-       int blocks = exbh->b_size >> inode->i_blkbits;
-       sector_t pblock = exbh->b_blocknr, cur_logical;
+       int blocks = map->m_len;
+       sector_t pblock = map->m_pblk, cur_logical;
        struct buffer_head *head, *bh;
        pgoff_t index, end;
        struct pagevec pvec;
        int nr_pages, i;
 
-       index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
-       end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+       index = map->m_lblk >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+       end = (map->m_lblk + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
        cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
 
        pagevec_init(&pvec, 0);
@@ -2098,17 +2072,16 @@ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
 
                        /* skip blocks out of the range */
                        do {
-                               if (cur_logical >= logical)
+                               if (cur_logical >= map->m_lblk)
                                        break;
                                cur_logical++;
                        } while ((bh = bh->b_this_page) != head);
 
                        do {
-                               if (cur_logical >= logical + blocks)
+                               if (cur_logical >= map->m_lblk + blocks)
                                        break;
 
-                               if (buffer_delay(bh) ||
-                                               buffer_unwritten(bh)) {
+                               if (buffer_delay(bh) || buffer_unwritten(bh)) {
 
                                        BUG_ON(bh->b_bdev != inode->i_sb->s_bdev);
 
@@ -2127,7 +2100,7 @@ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
                                } else if (buffer_mapped(bh))
                                        BUG_ON(bh->b_blocknr != pblock);
 
-                               if (buffer_uninit(exbh))
+                               if (map->m_flags & EXT4_MAP_UNINIT)
                                        set_buffer_uninit(bh);
                                cur_logical++;
                                pblock++;
@@ -2138,21 +2111,6 @@ static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
 }
 
 
-/*
- * __unmap_underlying_blocks - just a helper function to unmap
- * set of blocks described by @bh
- */
-static inline void __unmap_underlying_blocks(struct inode *inode,
-                                            struct buffer_head *bh)
-{
-       struct block_device *bdev = inode->i_sb->s_bdev;
-       int blocks, i;
-
-       blocks = bh->b_size >> inode->i_blkbits;
-       for (i = 0; i < blocks; i++)
-               unmap_underlying_metadata(bdev, bh->b_blocknr + i);
-}
-
 static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd,
                                        sector_t logical, long blk_cnt)
 {
@@ -2214,7 +2172,7 @@ static void ext4_print_free_blocks(struct inode *inode)
 static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 {
        int err, blks, get_blocks_flags;
-       struct buffer_head new;
+       struct ext4_map_blocks map;
        sector_t next = mpd->b_blocknr;
        unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits;
        loff_t disksize = EXT4_I(mpd->inode)->i_disksize;
@@ -2255,15 +2213,15 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
         * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
         * variables are updated after the blocks have been allocated.
         */
-       new.b_state = 0;
+       map.m_lblk = next;
+       map.m_len = max_blocks;
        get_blocks_flags = EXT4_GET_BLOCKS_CREATE;
        if (ext4_should_dioread_nolock(mpd->inode))
                get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
        if (mpd->b_state & (1 << BH_Delay))
                get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
 
-       blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks,
-                              &new, get_blocks_flags);
+       blks = ext4_map_blocks(handle, mpd->inode, &map, get_blocks_flags);
        if (blks < 0) {
                err = blks;
                /*
@@ -2305,10 +2263,13 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
        }
        BUG_ON(blks == 0);
 
-       new.b_size = (blks << mpd->inode->i_blkbits);
+       if (map.m_flags & EXT4_MAP_NEW) {
+               struct block_device *bdev = mpd->inode->i_sb->s_bdev;
+               int i;
 
-       if (buffer_new(&new))
-               __unmap_underlying_blocks(mpd->inode, &new);
+               for (i = 0; i < map.m_len; i++)
+                       unmap_underlying_metadata(bdev, map.m_pblk + i);
+       }
 
        /*
         * If blocks are delayed marked, we need to
@@ -2316,7 +2277,7 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
         */
        if ((mpd->b_state & (1 << BH_Delay)) ||
            (mpd->b_state & (1 << BH_Unwritten)))
-               mpage_put_bnr_to_bhs(mpd, next, &new);
+               mpage_put_bnr_to_bhs(mpd, &map);
 
        if (ext4_should_order_data(mpd->inode)) {
                err = ext4_jbd2_file_inode(handle, mpd->inode);
@@ -2534,8 +2495,9 @@ static int __mpage_da_writepage(struct page *page,
  * initialized properly.
  */
 static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
-                                 struct buffer_head *bh_result, int create)
+                                 struct buffer_head *bh, int create)
 {
+       struct ext4_map_blocks map;
        int ret = 0;
        sector_t invalid_block = ~((sector_t) 0xffff);
 
@@ -2543,16 +2505,22 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
                invalid_block = ~0;
 
        BUG_ON(create == 0);
-       BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
+       BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
+
+       map.m_lblk = iblock;
+       map.m_len = 1;
 
        /*
         * first, we need to know whether the block is allocated already
         * preallocated blocks are unmapped but should treated
         * the same as allocated blocks.
         */
-       ret = ext4_get_blocks(NULL, inode, iblock, 1,  bh_result, 0);
-       if ((ret == 0) && !buffer_delay(bh_result)) {
-               /* the block isn't (pre)allocated yet, let's reserve space */
+       ret = ext4_map_blocks(NULL, inode, &map, 0);
+       if (ret < 0)
+               return ret;
+       if (ret == 0) {
+               if (buffer_delay(bh))
+                       return 0; /* Not sure this could or should happen */
                /*
                 * XXX: __block_prepare_write() unmaps passed block,
                 * is it OK?
@@ -2562,26 +2530,26 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
                        /* not enough space to reserve */
                        return ret;
 
-               map_bh(bh_result, inode->i_sb, invalid_block);
-               set_buffer_new(bh_result);
-               set_buffer_delay(bh_result);
-       } else if (ret > 0) {
-               bh_result->b_size = (ret << inode->i_blkbits);
-               if (buffer_unwritten(bh_result)) {
-                       /* A delayed write to unwritten bh should
-                        * be marked new and mapped.  Mapped ensures
-                        * that we don't do get_block multiple times
-                        * when we write to the same offset and new
-                        * ensures that we do proper zero out for
-                        * partial write.
-                        */
-                       set_buffer_new(bh_result);
-                       set_buffer_mapped(bh_result);
-               }
-               ret = 0;
+               map_bh(bh, inode->i_sb, invalid_block);
+               set_buffer_new(bh);
+               set_buffer_delay(bh);
+               return 0;
        }
 
-       return ret;
+       map_bh(bh, inode->i_sb, map.m_pblk);
+       bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
+
+       if (buffer_unwritten(bh)) {
+               /* A delayed write to unwritten bh should be marked
+                * new and mapped.  Mapped ensures that we don't do
+                * get_block multiple times when we write to the same
+                * offset and new ensures that we do proper zero out
+                * for partial write.
+                */
+               set_buffer_new(bh);
+               set_buffer_mapped(bh);
+       }
+       return 0;
 }
 
 /*
@@ -2603,21 +2571,8 @@ static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
 static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
                                   struct buffer_head *bh_result, int create)
 {
-       int ret = 0;
-       unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
-
        BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
-
-       /*
-        * we don't want to do block allocation in writepage
-        * so call get_block_wrap with create = 0
-        */
-       ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0);
-       if (ret > 0) {
-               bh_result->b_size = (ret << inode->i_blkbits);
-               ret = 0;
-       }
-       return ret;
+       return _ext4_get_block(inode, iblock, bh_result, 0);
 }
 
 static int bget_one(handle_t *handle, struct buffer_head *bh)
@@ -3644,46 +3599,18 @@ out:
        return ret;
 }
 
+/*
+ * ext4_get_block used when preparing for a DIO write or buffer write.
+ * We allocate an uinitialized extent if blocks haven't been allocated.
+ * The extent will be converted to initialized after the IO is complete.
+ */
 static int ext4_get_block_write(struct inode *inode, sector_t iblock,
                   struct buffer_head *bh_result, int create)
 {
-       handle_t *handle = ext4_journal_current_handle();
-       int ret = 0;
-       unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
-       int dio_credits;
-       int started = 0;
-
        ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
                   inode->i_ino, create);
-       /*
-        * ext4_get_block in prepare for a DIO write or buffer write.
-        * We allocate an uinitialized extent if blocks haven't been allocated.
-        * The extent will be converted to initialized after IO complete.
-        */
-       create = EXT4_GET_BLOCKS_IO_CREATE_EXT;
-
-       if (!handle) {
-               if (max_blocks > DIO_MAX_BLOCKS)
-                       max_blocks = DIO_MAX_BLOCKS;
-               dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
-               handle = ext4_journal_start(inode, dio_credits);
-               if (IS_ERR(handle)) {
-                       ret = PTR_ERR(handle);
-                       goto out;
-               }
-               started = 1;
-       }
-
-       ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
-                             create);
-       if (ret > 0) {
-               bh_result->b_size = (ret << inode->i_blkbits);
-               ret = 0;
-       }
-       if (started)
-               ext4_journal_stop(handle);
-out:
-       return ret;
+       return _ext4_get_block(inode, iblock, bh_result,
+                              EXT4_GET_BLOCKS_IO_CREATE_EXT);
 }
 
 static void dump_completed_IO(struct inode * inode)