[GFS2] Add extent allocation to block allocator
Rather than having to allocate a single block at a time, this patch
allows the block allocator to allocate an extent. Since there is
no difference (so far as the block allocator is concerned) between
data blocks and indirect blocks, it is posible to allocate a single
extent and for the caller to unrevoke just the blocks required
for indirect blocks.
Currently the only bit of GFS2 to make use of this feature is the
build height function. The intention is that gfs2_block_map will
be changed to make use of this feature in future patches.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 274a2df..77eba0a 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -53,7 +53,8 @@
};
static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32 goal,
- unsigned char old_state, unsigned char new_state);
+ unsigned char old_state, unsigned char new_state,
+ unsigned int *n);
/**
* gfs2_setbit - Set a bit in the bitmaps
@@ -64,26 +65,32 @@
*
*/
-static void gfs2_setbit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
- unsigned int buflen, u32 block,
- unsigned char new_state)
+static inline void gfs2_setbit(struct gfs2_rgrpd *rgd, unsigned char *buf1,
+ unsigned char *buf2, unsigned int offset,
+ unsigned int buflen, u32 block,
+ unsigned char new_state)
{
- unsigned char *byte, *end, cur_state;
- unsigned int bit;
+ unsigned char *byte1, *byte2, *end, cur_state;
+ const unsigned int bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
- byte = buffer + (block / GFS2_NBBY);
- bit = (block % GFS2_NBBY) * GFS2_BIT_SIZE;
- end = buffer + buflen;
+ byte1 = buf1 + offset + (block / GFS2_NBBY);
+ end = buf1 + offset + buflen;
- gfs2_assert(rgd->rd_sbd, byte < end);
+ BUG_ON(byte1 >= end);
- cur_state = (*byte >> bit) & GFS2_BIT_MASK;
+ cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
- if (valid_change[new_state * 4 + cur_state]) {
- *byte ^= cur_state << bit;
- *byte |= new_state << bit;
- } else
+ if (unlikely(!valid_change[new_state * 4 + cur_state])) {
gfs2_consist_rgrpd(rgd);
+ return;
+ }
+ *byte1 ^= (cur_state ^ new_state) << bit;
+
+ if (buf2) {
+ byte2 = buf2 + offset + (block / GFS2_NBBY);
+ cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
+ *byte2 ^= (cur_state ^ new_state) << bit;
+ }
}
/**
@@ -94,10 +101,12 @@
*
*/
-static unsigned char gfs2_testbit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
- unsigned int buflen, u32 block)
+static inline unsigned char gfs2_testbit(struct gfs2_rgrpd *rgd,
+ const unsigned char *buffer,
+ unsigned int buflen, u32 block)
{
- unsigned char *byte, *end, cur_state;
+ const unsigned char *byte, *end;
+ unsigned char cur_state;
unsigned int bit;
byte = buffer + (block / GFS2_NBBY);
@@ -877,13 +886,15 @@
u32 goal = 0, block;
u64 no_addr;
struct gfs2_sbd *sdp = rgd->rd_sbd;
+ unsigned int n;
for(;;) {
if (goal >= rgd->rd_data)
break;
down_write(&sdp->sd_log_flush_lock);
+ n = 1;
block = rgblk_search(rgd, goal, GFS2_BLKST_UNLINKED,
- GFS2_BLKST_UNLINKED);
+ GFS2_BLKST_UNLINKED, &n);
up_write(&sdp->sd_log_flush_lock);
if (block == BFITNOENT)
break;
@@ -1280,6 +1291,7 @@
* @goal: the goal block within the RG (start here to search for avail block)
* @old_state: GFS2_BLKST_XXX the before-allocation state to find
* @new_state: GFS2_BLKST_XXX the after-allocation block state
+ * @n: The extent length
*
* Walk rgrp's bitmap to find bits that represent a block in @old_state.
* Add the found bitmap buffer to the transaction.
@@ -1295,13 +1307,17 @@
*/
static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32 goal,
- unsigned char old_state, unsigned char new_state)
+ unsigned char old_state, unsigned char new_state,
+ unsigned int *n)
{
struct gfs2_bitmap *bi = NULL;
- u32 length = rgd->rd_length;
+ const u32 length = rgd->rd_length;
u32 blk = 0;
unsigned int buf, x;
+ const unsigned int elen = *n;
+ const u8 *buffer;
+ *n = 0;
/* Find bitmap block that contains bits for goal block */
for (buf = 0; buf < length; buf++) {
bi = rgd->rd_bits + buf;
@@ -1322,7 +1338,7 @@
for (x = 0; x <= length; x++) {
/* The GFS2_BLKST_UNLINKED state doesn't apply to the clone
bitmaps, so we must search the originals for that. */
- const u8 *buffer = bi->bi_bh->b_data + bi->bi_offset;
+ buffer = bi->bi_bh->b_data + bi->bi_offset;
if (old_state != GFS2_BLKST_UNLINKED && bi->bi_clone)
buffer = bi->bi_clone + bi->bi_offset;
@@ -1337,12 +1353,21 @@
}
if (blk != BFITNOENT && old_state != new_state) {
+ *n = 1;
gfs2_trans_add_bh(rgd->rd_gl, bi->bi_bh, 1);
- gfs2_setbit(rgd, bi->bi_bh->b_data + bi->bi_offset,
+ gfs2_setbit(rgd, bi->bi_bh->b_data, bi->bi_clone, bi->bi_offset,
bi->bi_len, blk, new_state);
- if (bi->bi_clone)
- gfs2_setbit(rgd, bi->bi_clone + bi->bi_offset,
- bi->bi_len, blk, new_state);
+ while(*n < elen) {
+ goal++;
+ if (goal >= (bi->bi_len / GFS2_NBBY))
+ break;
+ if (gfs2_testbit(rgd, buffer, bi->bi_len, goal) !=
+ GFS2_BLKST_FREE)
+ break;
+ (*n)++;
+ gfs2_setbit(rgd, bi->bi_bh->b_data, bi->bi_clone,
+ bi->bi_offset, bi->bi_len, blk, new_state);
+ }
}
return (blk == BFITNOENT) ? blk : (bi->bi_start * GFS2_NBBY) + blk;
@@ -1397,7 +1422,7 @@
bi->bi_len);
}
gfs2_trans_add_bh(rgd->rd_gl, bi->bi_bh, 1);
- gfs2_setbit(rgd, bi->bi_bh->b_data + bi->bi_offset,
+ gfs2_setbit(rgd, bi->bi_bh->b_data, NULL, bi->bi_offset,
bi->bi_len, buf_blk, new_state);
}
@@ -1411,7 +1436,7 @@
* Returns: the allocated block
*/
-u64 gfs2_alloc_block(struct gfs2_inode *ip)
+u64 gfs2_alloc_block(struct gfs2_inode *ip, unsigned int *n)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al = ip->i_alloc;
@@ -1424,26 +1449,26 @@
else
goal = rgd->rd_last_alloc;
- blk = rgblk_search(rgd, goal, GFS2_BLKST_FREE, GFS2_BLKST_USED);
+ blk = rgblk_search(rgd, goal, GFS2_BLKST_FREE, GFS2_BLKST_USED, n);
BUG_ON(blk == BFITNOENT);
- rgd->rd_last_alloc = blk;
+ rgd->rd_last_alloc = blk;
block = rgd->rd_data0 + blk;
ip->i_goal = block;
- gfs2_assert_withdraw(sdp, rgd->rd_rg.rg_free);
- rgd->rd_rg.rg_free--;
+ gfs2_assert_withdraw(sdp, rgd->rd_rg.rg_free >= *n);
+ rgd->rd_rg.rg_free -= *n;
gfs2_trans_add_bh(rgd->rd_gl, rgd->rd_bits[0].bi_bh, 1);
gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
- al->al_alloced++;
+ al->al_alloced += *n;
- gfs2_statfs_change(sdp, 0, -1, 0);
- gfs2_quota_change(ip, +1, ip->i_inode.i_uid, ip->i_inode.i_gid);
+ gfs2_statfs_change(sdp, 0, -*n, 0);
+ gfs2_quota_change(ip, *n, ip->i_inode.i_uid, ip->i_inode.i_gid);
spin_lock(&sdp->sd_rindex_spin);
- rgd->rd_free_clone--;
+ rgd->rd_free_clone -= *n;
spin_unlock(&sdp->sd_rindex_spin);
return block;
@@ -1463,9 +1488,10 @@
struct gfs2_rgrpd *rgd = al->al_rgd;
u32 blk;
u64 block;
+ unsigned int n = 1;
blk = rgblk_search(rgd, rgd->rd_last_alloc,
- GFS2_BLKST_FREE, GFS2_BLKST_DINODE);
+ GFS2_BLKST_FREE, GFS2_BLKST_DINODE, &n);
BUG_ON(blk == BFITNOENT);
rgd->rd_last_alloc = blk;