return count;
}
-/**
- * ext4_alloc_blocks: multiple allocate blocks needed for a branch
- * @handle: handle for this transaction
- * @inode: inode which needs allocated blocks
- * @iblock: the logical block to start allocated at
- * @goal: preferred physical block of allocation
- * @indirect_blks: the number of blocks need to allocate for indirect
- * blocks
- * @blks: number of desired blocks
- * @new_blocks: on return it will store the new block numbers for
- * the indirect blocks(if needed) and the first direct block,
- * @err: on return it will store the error code
- *
- * This function will return the number of blocks allocated as
- * requested by the passed-in parameters.
- */
-static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
- ext4_lblk_t iblock, ext4_fsblk_t goal,
- int indirect_blks, int blks,
- ext4_fsblk_t new_blocks[4], int *err)
-{
- struct ext4_allocation_request ar;
- int target, i;
- unsigned long count = 0, blk_allocated = 0;
- int index = 0;
- ext4_fsblk_t current_block = 0;
- int ret = 0;
-
- /*
- * Here we try to allocate the requested multiple blocks at once,
- * on a best-effort basis.
- * To build a branch, we should allocate blocks for
- * the indirect blocks(if not allocated yet), and at least
- * the first direct block of this branch. That's the
- * minimum number of blocks need to allocate(required)
- */
- /* first we try to allocate the indirect blocks */
- target = indirect_blks;
- while (target > 0) {
- count = target;
- /* allocating blocks for indirect blocks and direct blocks */
- current_block = ext4_new_meta_blocks(handle, inode, goal,
- 0, &count, err);
- if (*err)
- goto failed_out;
-
- if (unlikely(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS)) {
- EXT4_ERROR_INODE(inode,
- "current_block %llu + count %lu > %d!",
- current_block, count,
- EXT4_MAX_BLOCK_FILE_PHYS);
- *err = -EIO;
- goto failed_out;
- }
-
- target -= count;
- /* allocate blocks for indirect blocks */
- while (index < indirect_blks && count) {
- new_blocks[index++] = current_block++;
- count--;
- }
- if (count > 0) {
- /*
- * save the new block number
- * for the first direct block
- */
- new_blocks[index] = current_block;
- WARN(1, KERN_INFO "%s returned more blocks than "
- "requested\n", __func__);
- break;
- }
- }
-
- target = blks - count ;
- blk_allocated = count;
- if (!target)
- goto allocated;
- /* Now allocate data blocks */
- memset(&ar, 0, sizeof(ar));
- ar.inode = inode;
- ar.goal = goal;
- ar.len = target;
- ar.logical = iblock;
- if (S_ISREG(inode->i_mode))
- /* enable in-core preallocation only for regular files */
- ar.flags = EXT4_MB_HINT_DATA;
-
- current_block = ext4_mb_new_blocks(handle, &ar, err);
- if (unlikely(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS)) {
- EXT4_ERROR_INODE(inode,
- "current_block %llu + ar.len %d > %d!",
- current_block, ar.len,
- EXT4_MAX_BLOCK_FILE_PHYS);
- *err = -EIO;
- goto failed_out;
- }
-
- if (*err && (target == blks)) {
- /*
- * if the allocation failed and we didn't allocate
- * any blocks before
- */
- goto failed_out;
- }
- if (!*err) {
- if (target == blks) {
- /*
- * save the new block number
- * for the first direct block
- */
- new_blocks[index] = current_block;
- }
- blk_allocated += ar.len;
- }
-allocated:
- /* total number of blocks allocated for direct blocks */
- ret = blk_allocated;
- *err = 0;
- return ret;
-failed_out:
- for (i = 0; i < index; i++)
- ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1, 0);
- return ret;
-}
-
/**
* ext4_alloc_branch - allocate and set up a chain of blocks.
* @handle: handle for this transaction
int *blks, ext4_fsblk_t goal,
ext4_lblk_t *offsets, Indirect *branch)
{
- int blocksize = inode->i_sb->s_blocksize;
- int i, n = 0;
- int err = 0;
- struct buffer_head *bh;
- int num;
- ext4_fsblk_t new_blocks[4];
- ext4_fsblk_t current_block;
+ struct ext4_allocation_request ar;
+ struct buffer_head * bh;
+ ext4_fsblk_t b, new_blocks[4];
+ __le32 *p;
+ int i, j, err, len = 1;
- num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks,
- *blks, new_blocks, &err);
- if (err)
- return err;
-
- branch[0].key = cpu_to_le32(new_blocks[0]);
/*
- * metadata blocks and data blocks are allocated.
+ * Set up for the direct block allocation
*/
- for (n = 1; n <= indirect_blks; n++) {
- /*
- * Get buffer_head for parent block, zero it out
- * and set the pointer to new one, then send
- * parent to disk.
- */
- bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
+ memset(&ar, 0, sizeof(ar));
+ ar.inode = inode;
+ ar.len = *blks;
+ ar.logical = iblock;
+ if (S_ISREG(inode->i_mode))
+ ar.flags = EXT4_MB_HINT_DATA;
+
+ for (i = 0; i <= indirect_blks; i++) {
+ if (i == indirect_blks) {
+ ar.goal = goal;
+ new_blocks[i] = ext4_mb_new_blocks(handle, &ar, &err);
+ } else
+ goal = new_blocks[i] = ext4_new_meta_blocks(handle, inode,
+ goal, 0, NULL, &err);
+ if (err) {
+ i--;
+ goto failed;
+ }
+ branch[i].key = cpu_to_le32(new_blocks[i]);
+ if (i == 0)
+ continue;
+
+ bh = branch[i].bh = sb_getblk(inode->i_sb, new_blocks[i-1]);
if (unlikely(!bh)) {
err = -ENOMEM;
goto failed;
}
-
- branch[n].bh = bh;
lock_buffer(bh);
BUFFER_TRACE(bh, "call get_create_access");
err = ext4_journal_get_create_access(handle, bh);
if (err) {
- /* Don't brelse(bh) here; it's done in
- * ext4_journal_forget() below */
unlock_buffer(bh);
goto failed;
}
- memset(bh->b_data, 0, blocksize);
- branch[n].p = (__le32 *) bh->b_data + offsets[n];
- branch[n].key = cpu_to_le32(new_blocks[n]);
- *branch[n].p = branch[n].key;
- if (n == indirect_blks) {
- current_block = new_blocks[n];
- /*
- * End of chain, update the last new metablock of
- * the chain to point to the new allocated
- * data blocks numbers
- */
- for (i = 1; i < num; i++)
- *(branch[n].p + i) = cpu_to_le32(++current_block);
- }
+ memset(bh->b_data, 0, bh->b_size);
+ p = branch[i].p = (__le32 *) bh->b_data + offsets[i];
+ b = new_blocks[i];
+
+ if (i == indirect_blks)
+ len = ar.len;
+ for (j = 0; j < len; j++)
+ *p++ = cpu_to_le32(b++);
+
BUFFER_TRACE(bh, "marking uptodate");
set_buffer_uptodate(bh);
unlock_buffer(bh);
if (err)
goto failed;
}
- *blks = num;
- return err;
+ *blks = ar.len;
+ return 0;
failed:
- /* Allocation failed, free what we already allocated */
- ext4_free_blocks(handle, inode, NULL, new_blocks[0], 1, 0);
- for (i = 1; i <= n ; i++) {
- /*
- * branch[i].bh is newly allocated, so there is no
- * need to revoke the block, which is why we don't
- * need to set EXT4_FREE_BLOCKS_METADATA.
- */
- ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1,
- EXT4_FREE_BLOCKS_FORGET);
+ for (; i >= 0; i--) {
+ if (i != indirect_blks && branch[i].bh)
+ ext4_forget(handle, 1, inode, branch[i].bh,
+ branch[i].bh->b_blocknr);
+ ext4_free_blocks(handle, inode, NULL, new_blocks[i],
+ (i == indirect_blks) ? ar.len : 1, 0);
}
- for (i = n+1; i < indirect_blks; i++)
- ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1, 0);
-
- ext4_free_blocks(handle, inode, NULL, new_blocks[i], num, 0);
-
return err;
}
projects / ~andy / linux / commitdiff