clear_inode(inode); /* We must guarantee clearing of inode... */
}
-static int ext3_alloc_block (handle_t *handle,
- struct inode * inode, unsigned long goal, int *err)
-{
- unsigned long result;
-
- result = ext3_new_block(handle, inode, goal, err);
- return result;
-}
-
-
typedef struct {
__le32 *p;
__le32 key;
return ext3_find_near(inode, partial);
}
+/**
+ * ext3_blks_to_allocate: Look up the block map and count the number
+ * of direct blocks need to be allocated for the given branch.
+ *
+ * @branch: chain of indirect blocks
+ * @k: number of blocks need for indirect blocks
+ * @blks: number of data blocks to be mapped.
+ * @blocks_to_boundary: the offset in the indirect block
+ *
+ * return the total number of blocks to be allocate, including the
+ * direct and indirect blocks.
+ */
+static int
+ext3_blks_to_allocate(Indirect * branch, int k, unsigned long blks,
+ int blocks_to_boundary)
+{
+ unsigned long count = 0;
+
+ /*
+ * Simple case, [t,d]Indirect block(s) has not allocated yet
+ * then it's clear blocks on that path have not allocated
+ */
+ if (k > 0) {
+ /* right now don't hanel cross boundary allocation */
+ if (blks < blocks_to_boundary + 1)
+ count += blks;
+ else
+ count += blocks_to_boundary + 1;
+ return count;
+ }
+
+ count++;
+ while (count < blks && count <= blocks_to_boundary &&
+ le32_to_cpu(*(branch[0].p + count)) == 0) {
+ count++;
+ }
+ return count;
+}
+
+/**
+ * ext3_alloc_blocks: multiple allocate blocks needed for a branch
+ * @indirect_blks: the number of blocks need to allocate for indirect
+ * blocks
+ *
+ * @new_blocks: on return it will store the new block numbers for
+ * the indirect blocks(if needed) and the first direct block,
+ * @blks: on return it will store the total number of allocated
+ * direct blocks
+ */
+static int ext3_alloc_blocks(handle_t *handle, struct inode *inode,
+ unsigned long goal, int indirect_blks, int blks,
+ unsigned long long new_blocks[4], int *err)
+{
+ int target, i;
+ unsigned long count = 0;
+ int index = 0;
+ unsigned long 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)
+ */
+ target = blks + indirect_blks;
+
+ while (1) {
+ count = target;
+ /* allocating blocks for indirect blocks and direct blocks */
+ current_block = ext3_new_blocks(handle, inode, goal, &count, err);
+ if (*err)
+ goto failed_out;
+
+ target -= count;
+ /* allocate blocks for indirect blocks */
+ while (index < indirect_blks && count) {
+ new_blocks[index++] = current_block++;
+ count--;
+ }
+
+ if (count > 0)
+ break;
+ }
+
+ /* save the new block number for the first direct block */
+ new_blocks[index] = current_block;
+
+ /* total number of blocks allocated for direct blocks */
+ ret = count;
+ *err = 0;
+ return ret;
+failed_out:
+ for (i = 0; i <index; i++)
+ ext3_free_blocks(handle, inode, new_blocks[i], 1);
+ return ret;
+}
/**
* ext3_alloc_branch - allocate and set up a chain of blocks.
* @inode: owner
- * @num: depth of the chain (number of blocks to allocate)
+ * @indirect_blks: number of allocated indirect blocks
+ * @blks: number of allocated direct blocks
* @offsets: offsets (in the blocks) to store the pointers to next.
* @branch: place to store the chain in.
*
- * This function allocates @num blocks, zeroes out all but the last one,
+ * This function allocates blocks, zeroes out all but the last one,
* links them into chain and (if we are synchronous) writes them to disk.
* In other words, it prepares a branch that can be spliced onto the
* inode. It stores the information about that chain in the branch[], in
*/
static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
- int num,
- unsigned long goal,
- int *offsets,
- Indirect *branch)
+ int indirect_blks, int *blks, unsigned long goal,
+ int *offsets, Indirect *branch)
{
int blocksize = inode->i_sb->s_blocksize;
- int n = 0, keys = 0;
+ int i, n = 0;
int err = 0;
- int i;
- int parent = ext3_alloc_block(handle, inode, goal, &err);
-
- branch[0].key = cpu_to_le32(parent);
- if (parent) {
- for (n = 1; n < num; n++) {
- struct buffer_head *bh;
- /* Allocate the next block */
- int nr = ext3_alloc_block(handle, inode, parent, &err);
- if (!nr)
- break;
- branch[n].key = cpu_to_le32(nr);
+ struct buffer_head *bh;
+ int num;
+ unsigned long long new_blocks[4];
+ unsigned long long current_block;
- /*
- * 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, parent);
- if (!bh)
- break;
- keys = n+1;
- branch[n].bh = bh;
- lock_buffer(bh);
- BUFFER_TRACE(bh, "call get_create_access");
- err = ext3_journal_get_create_access(handle, bh);
- if (err) {
- unlock_buffer(bh);
- brelse(bh);
- break;
- }
+ num = ext3_alloc_blocks(handle, inode, goal, indirect_blks,
+ *blks, new_blocks, &err);
+ if (err)
+ return err;
- memset(bh->b_data, 0, blocksize);
- branch[n].p = (__le32*) bh->b_data + offsets[n];
- *branch[n].p = branch[n].key;
- BUFFER_TRACE(bh, "marking uptodate");
- set_buffer_uptodate(bh);
+ branch[0].key = cpu_to_le32(new_blocks[0]);
+ /*
+ * metadata blocks and data blocks are allocated.
+ */
+ 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]);
+ branch[n].bh = bh;
+ lock_buffer(bh);
+ BUFFER_TRACE(bh, "call get_create_access");
+ err = ext3_journal_get_create_access(handle, bh);
+ if (err) {
unlock_buffer(bh);
+ brelse(bh);
+ goto failed;
+ }
- BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
- err = ext3_journal_dirty_metadata(handle, bh);
- if (err)
- break;
-
- parent = nr;
+ 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);
}
- }
- if (n == num)
- return 0;
+ BUFFER_TRACE(bh, "marking uptodate");
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+ BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
+ err = ext3_journal_dirty_metadata(handle, bh);
+ if (err)
+ goto failed;
+ }
+ *blks = num;
+ return err;
+failed:
/* Allocation failed, free what we already allocated */
- for (i = 1; i < keys; i++) {
+ for (i = 1; i <= n ; i++) {
BUFFER_TRACE(branch[i].bh, "call journal_forget");
ext3_journal_forget(handle, branch[i].bh);
}
- for (i = 0; i < keys; i++)
- ext3_free_blocks(handle, inode, le32_to_cpu(branch[i].key), 1);
+ for (i = 0; i <indirect_blks; i++)
+ ext3_free_blocks(handle, inode, new_blocks[i], 1);
+
+ ext3_free_blocks(handle, inode, new_blocks[i], num);
+
return err;
}
* @chain: chain of indirect blocks (with a missing link - see
* ext3_alloc_branch)
* @where: location of missing link
- * @num: number of blocks we are adding
+ * @num: number of indirect blocks we are adding
+ * @blks: number of direct blocks we are adding
*
* This function fills the missing link and does all housekeeping needed in
* inode (->i_blocks, etc.). In case of success we end up with the full
*/
static int ext3_splice_branch(handle_t *handle, struct inode *inode, long block,
- Indirect chain[4], Indirect *where, int num)
+ Indirect *where, int num, int blks)
{
int i;
int err = 0;
struct ext3_block_alloc_info *block_i = EXT3_I(inode)->i_block_alloc_info;
-
+ unsigned long current_block;
/*
* If we're splicing into a [td]indirect block (as opposed to the
* inode) then we need to get write access to the [td]indirect block
/* That's it */
*where->p = where->key;
+ /* update host bufferhead or inode to point to
+ * more just allocated direct blocks blocks */
+ if (num == 0 && blks > 1) {
+ current_block = le32_to_cpu(where->key + 1);
+ for (i = 1; i < blks; i++)
+ *(where->p + i ) = cpu_to_le32(current_block++);
+ }
/*
* update the most recently allocated logical & physical block
* allocation
*/
if (block_i) {
- block_i->last_alloc_logical_block = block;
- block_i->last_alloc_physical_block = le32_to_cpu(where[num-1].key);
+ block_i->last_alloc_logical_block = block + blks - 1;
+ block_i->last_alloc_physical_block = le32_to_cpu(where[num].key + blks - 1);
}
/* We are done with atomic stuff, now do the rest of housekeeping */
return err;
err_out:
- for (i = 1; i < num; i++) {
+ for (i = 1; i <= num; i++) {
BUFFER_TRACE(where[i].bh, "call journal_forget");
ext3_journal_forget(handle, where[i].bh);
+ ext3_free_blocks(handle, inode, le32_to_cpu(where[i-1].key), 1);
}
+ ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
+
return err;
}
Indirect chain[4];
Indirect *partial;
unsigned long goal;
- int left;
+ int indirect_blks;
int blocks_to_boundary = 0;
int depth;
struct ext3_inode_info *ei = EXT3_I(inode);
goal = ext3_find_goal(inode, iblock, chain, partial);
- left = (chain + depth) - partial;
+ /* the number of blocks need to allocate for [d,t]indirect blocks */
+ indirect_blks = (chain + depth) - partial - 1;
+ /*
+ * Next look up the indirect map to count the totoal number of
+ * direct blocks to allocate for this branch.
+ */
+ count = ext3_blks_to_allocate(partial, indirect_blks,
+ maxblocks, blocks_to_boundary);
/*
* Block out ext3_truncate while we alter the tree
*/
- err = ext3_alloc_branch(handle, inode, left, goal,
+ err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal,
offsets + (partial - chain), partial);
/*
* may need to return -EAGAIN upwards in the worst case. --sct
*/
if (!err)
- err = ext3_splice_branch(handle, inode, iblock, chain,
- partial, left);
+ err = ext3_splice_branch(handle, inode, iblock,
+ partial, indirect_blks, count);
/*
* i_disksize growing is protected by truncate_mutex. Don't forget to
* protect it if you're about to implement concurrent
static int
ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock,
- unsigned long max_blocks, struct buffer_head *bh_result,
- int create)
+ unsigned long max_blocks,
+ struct buffer_head *bh_result, int create)
{
handle_t *handle = journal_current_handle();
int ret = 0;
projects / openwrt / staging / blogic.git / commitdiff