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Diffstat (limited to 'fs/xfs/xfs_dir2_block.c')
-rw-r--r--fs/xfs/xfs_dir2_block.c386
1 files changed, 209 insertions, 177 deletions
diff --git a/fs/xfs/xfs_dir2_block.c b/fs/xfs/xfs_dir2_block.c
index 53666ca6c953..25ce409487be 100644
--- a/fs/xfs/xfs_dir2_block.c
+++ b/fs/xfs/xfs_dir2_block.c
@@ -56,6 +56,178 @@ xfs_dir_startup(void)
xfs_dir_hash_dotdot = xfs_da_hashname((unsigned char *)"..", 2);
}
+static int
+xfs_dir2_block_read(
+ struct xfs_trans *tp,
+ struct xfs_inode *dp,
+ struct xfs_buf **bpp)
+{
+ struct xfs_mount *mp = dp->i_mount;
+
+ return xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, bpp,
+ XFS_DATA_FORK, NULL);
+}
+
+static void
+xfs_dir2_block_need_space(
+ struct xfs_dir2_data_hdr *hdr,
+ struct xfs_dir2_block_tail *btp,
+ struct xfs_dir2_leaf_entry *blp,
+ __be16 **tagpp,
+ struct xfs_dir2_data_unused **dupp,
+ struct xfs_dir2_data_unused **enddupp,
+ int *compact,
+ int len)
+{
+ struct xfs_dir2_data_free *bf;
+ __be16 *tagp = NULL;
+ struct xfs_dir2_data_unused *dup = NULL;
+ struct xfs_dir2_data_unused *enddup = NULL;
+
+ *compact = 0;
+ bf = hdr->bestfree;
+
+ /*
+ * If there are stale entries we'll use one for the leaf.
+ */
+ if (btp->stale) {
+ if (be16_to_cpu(bf[0].length) >= len) {
+ /*
+ * The biggest entry enough to avoid compaction.
+ */
+ dup = (xfs_dir2_data_unused_t *)
+ ((char *)hdr + be16_to_cpu(bf[0].offset));
+ goto out;
+ }
+
+ /*
+ * Will need to compact to make this work.
+ * Tag just before the first leaf entry.
+ */
+ *compact = 1;
+ tagp = (__be16 *)blp - 1;
+
+ /* Data object just before the first leaf entry. */
+ dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
+
+ /*
+ * If it's not free then the data will go where the
+ * leaf data starts now, if it works at all.
+ */
+ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
+ if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
+ (uint)sizeof(*blp) < len)
+ dup = NULL;
+ } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
+ dup = NULL;
+ else
+ dup = (xfs_dir2_data_unused_t *)blp;
+ goto out;
+ }
+
+ /*
+ * no stale entries, so just use free space.
+ * Tag just before the first leaf entry.
+ */
+ tagp = (__be16 *)blp - 1;
+
+ /* Data object just before the first leaf entry. */
+ enddup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
+
+ /*
+ * If it's not free then can't do this add without cleaning up:
+ * the space before the first leaf entry needs to be free so it
+ * can be expanded to hold the pointer to the new entry.
+ */
+ if (be16_to_cpu(enddup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
+ /*
+ * Check out the biggest freespace and see if it's the same one.
+ */
+ dup = (xfs_dir2_data_unused_t *)
+ ((char *)hdr + be16_to_cpu(bf[0].offset));
+ if (dup != enddup) {
+ /*
+ * Not the same free entry, just check its length.
+ */
+ if (be16_to_cpu(dup->length) < len)
+ dup = NULL;
+ goto out;
+ }
+
+ /*
+ * It is the biggest freespace, can it hold the leaf too?
+ */
+ if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
+ /*
+ * Yes, use the second-largest entry instead if it works.
+ */
+ if (be16_to_cpu(bf[1].length) >= len)
+ dup = (xfs_dir2_data_unused_t *)
+ ((char *)hdr + be16_to_cpu(bf[1].offset));
+ else
+ dup = NULL;
+ }
+ }
+out:
+ *tagpp = tagp;
+ *dupp = dup;
+ *enddupp = enddup;
+}
+
+/*
+ * compact the leaf entries.
+ * Leave the highest-numbered stale entry stale.
+ * XXX should be the one closest to mid but mid is not yet computed.
+ */
+static void
+xfs_dir2_block_compact(
+ struct xfs_trans *tp,
+ struct xfs_buf *bp,
+ struct xfs_dir2_data_hdr *hdr,
+ struct xfs_dir2_block_tail *btp,
+ struct xfs_dir2_leaf_entry *blp,
+ int *needlog,
+ int *lfloghigh,
+ int *lfloglow)
+{
+ int fromidx; /* source leaf index */
+ int toidx; /* target leaf index */
+ int needscan = 0;
+ int highstale; /* high stale index */
+
+ fromidx = toidx = be32_to_cpu(btp->count) - 1;
+ highstale = *lfloghigh = -1;
+ for (; fromidx >= 0; fromidx--) {
+ if (blp[fromidx].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
+ if (highstale == -1)
+ highstale = toidx;
+ else {
+ if (*lfloghigh == -1)
+ *lfloghigh = toidx;
+ continue;
+ }
+ }
+ if (fromidx < toidx)
+ blp[toidx] = blp[fromidx];
+ toidx--;
+ }
+ *lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
+ *lfloghigh -= be32_to_cpu(btp->stale) - 1;
+ be32_add_cpu(&btp->count, -(be32_to_cpu(btp->stale) - 1));
+ xfs_dir2_data_make_free(tp, bp,
+ (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
+ (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
+ needlog, &needscan);
+ blp += be32_to_cpu(btp->stale) - 1;
+ btp->stale = cpu_to_be32(1);
+ /*
+ * If we now need to rebuild the bestfree map, do so.
+ * This needs to happen before the next call to use_free.
+ */
+ if (needscan)
+ xfs_dir2_data_freescan(tp->t_mountp, hdr, needlog);
+}
+
/*
* Add an entry to a block directory.
*/
@@ -63,7 +235,6 @@ int /* error */
xfs_dir2_block_addname(
xfs_da_args_t *args) /* directory op arguments */
{
- xfs_dir2_data_free_t *bf; /* bestfree table in block */
xfs_dir2_data_hdr_t *hdr; /* block header */
xfs_dir2_leaf_entry_t *blp; /* block leaf entries */
struct xfs_buf *bp; /* buffer for block */
@@ -94,134 +265,44 @@ xfs_dir2_block_addname(
dp = args->dp;
tp = args->trans;
mp = dp->i_mount;
- /*
- * Read the (one and only) directory block into dabuf bp.
- */
- error = xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &bp,
- XFS_DATA_FORK, NULL);
+
+ /* Read the (one and only) directory block into bp. */
+ error = xfs_dir2_block_read(tp, dp, &bp);
if (error)
return error;
- ASSERT(bp != NULL);
- hdr = bp->b_addr;
- /*
- * Check the magic number, corrupted if wrong.
- */
- if (unlikely(hdr->magic != cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))) {
- XFS_CORRUPTION_ERROR("xfs_dir2_block_addname",
- XFS_ERRLEVEL_LOW, mp, hdr);
- xfs_trans_brelse(tp, bp);
- return XFS_ERROR(EFSCORRUPTED);
- }
+
len = xfs_dir2_data_entsize(args->namelen);
+
/*
* Set up pointers to parts of the block.
*/
- bf = hdr->bestfree;
+ hdr = bp->b_addr;
btp = xfs_dir2_block_tail_p(mp, hdr);
blp = xfs_dir2_block_leaf_p(btp);
+
/*
- * No stale entries? Need space for entry and new leaf.
- */
- if (!btp->stale) {
- /*
- * Tag just before the first leaf entry.
- */
- tagp = (__be16 *)blp - 1;
- /*
- * Data object just before the first leaf entry.
- */
- enddup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
- /*
- * If it's not free then can't do this add without cleaning up:
- * the space before the first leaf entry needs to be free so it
- * can be expanded to hold the pointer to the new entry.
- */
- if (be16_to_cpu(enddup->freetag) != XFS_DIR2_DATA_FREE_TAG)
- dup = enddup = NULL;
- /*
- * Check out the biggest freespace and see if it's the same one.
- */
- else {
- dup = (xfs_dir2_data_unused_t *)
- ((char *)hdr + be16_to_cpu(bf[0].offset));
- if (dup == enddup) {
- /*
- * It is the biggest freespace, is it too small
- * to hold the new leaf too?
- */
- if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
- /*
- * Yes, we use the second-largest
- * entry instead if it works.
- */
- if (be16_to_cpu(bf[1].length) >= len)
- dup = (xfs_dir2_data_unused_t *)
- ((char *)hdr +
- be16_to_cpu(bf[1].offset));
- else
- dup = NULL;
- }
- } else {
- /*
- * Not the same free entry,
- * just check its length.
- */
- if (be16_to_cpu(dup->length) < len) {
- dup = NULL;
- }
- }
- }
- compact = 0;
- }
- /*
- * If there are stale entries we'll use one for the leaf.
- * Is the biggest entry enough to avoid compaction?
- */
- else if (be16_to_cpu(bf[0].length) >= len) {
- dup = (xfs_dir2_data_unused_t *)
- ((char *)hdr + be16_to_cpu(bf[0].offset));
- compact = 0;
- }
- /*
- * Will need to compact to make this work.
+ * Find out if we can reuse stale entries or whether we need extra
+ * space for entry and new leaf.
*/
- else {
- /*
- * Tag just before the first leaf entry.
- */
- tagp = (__be16 *)blp - 1;
- /*
- * Data object just before the first leaf entry.
- */
- dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
- /*
- * If it's not free then the data will go where the
- * leaf data starts now, if it works at all.
- */
- if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
- if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
- (uint)sizeof(*blp) < len)
- dup = NULL;
- } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
- dup = NULL;
- else
- dup = (xfs_dir2_data_unused_t *)blp;
- compact = 1;
- }
+ xfs_dir2_block_need_space(hdr, btp, blp, &tagp, &dup,
+ &enddup, &compact, len);
+
/*
- * If this isn't a real add, we're done with the buffer.
+ * Done everything we need for a space check now.
*/
- if (args->op_flags & XFS_DA_OP_JUSTCHECK)
+ if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
xfs_trans_brelse(tp, bp);
+ if (!dup)
+ return XFS_ERROR(ENOSPC);
+ return 0;
+ }
+
/*
* If we don't have space for the new entry & leaf ...
*/
if (!dup) {
- /*
- * Not trying to actually do anything, or don't have
- * a space reservation: return no-space.
- */
- if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
+ /* Don't have a space reservation: return no-space. */
+ if (args->total == 0)
return XFS_ERROR(ENOSPC);
/*
* Convert to the next larger format.
@@ -232,65 +313,24 @@ xfs_dir2_block_addname(
return error;
return xfs_dir2_leaf_addname(args);
}
- /*
- * Just checking, and it would work, so say so.
- */
- if (args->op_flags & XFS_DA_OP_JUSTCHECK)
- return 0;
+
needlog = needscan = 0;
+
/*
* If need to compact the leaf entries, do it now.
- * Leave the highest-numbered stale entry stale.
- * XXX should be the one closest to mid but mid is not yet computed.
- */
- if (compact) {
- int fromidx; /* source leaf index */
- int toidx; /* target leaf index */
-
- for (fromidx = toidx = be32_to_cpu(btp->count) - 1,
- highstale = lfloghigh = -1;
- fromidx >= 0;
- fromidx--) {
- if (blp[fromidx].address ==
- cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
- if (highstale == -1)
- highstale = toidx;
- else {
- if (lfloghigh == -1)
- lfloghigh = toidx;
- continue;
- }
- }
- if (fromidx < toidx)
- blp[toidx] = blp[fromidx];
- toidx--;
- }
- lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
- lfloghigh -= be32_to_cpu(btp->stale) - 1;
- be32_add_cpu(&btp->count, -(be32_to_cpu(btp->stale) - 1));
- xfs_dir2_data_make_free(tp, bp,
- (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
- (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
- &needlog, &needscan);
- blp += be32_to_cpu(btp->stale) - 1;
- btp->stale = cpu_to_be32(1);
- /*
- * If we now need to rebuild the bestfree map, do so.
- * This needs to happen before the next call to use_free.
- */
- if (needscan) {
- xfs_dir2_data_freescan(mp, hdr, &needlog);
- needscan = 0;
- }
- }
- /*
- * Set leaf logging boundaries to impossible state.
- * For the no-stale case they're set explicitly.
*/
+ if (compact)
+ xfs_dir2_block_compact(tp, bp, hdr, btp, blp, &needlog,
+ &lfloghigh, &lfloglow);
else if (btp->stale) {
+ /*
+ * Set leaf logging boundaries to impossible state.
+ * For the no-stale case they're set explicitly.
+ */
lfloglow = be32_to_cpu(btp->count);
lfloghigh = -1;
}
+
/*
* Find the slot that's first lower than our hash value, -1 if none.
*/
@@ -450,18 +490,13 @@ xfs_dir2_block_getdents(
/*
* If the block number in the offset is out of range, we're done.
*/
- if (xfs_dir2_dataptr_to_db(mp, *offset) > mp->m_dirdatablk) {
+ if (xfs_dir2_dataptr_to_db(mp, *offset) > mp->m_dirdatablk)
return 0;
- }
- /*
- * Can't read the block, give up, else get dabuf in bp.
- */
- error = xfs_da_read_buf(NULL, dp, mp->m_dirdatablk, -1,
- &bp, XFS_DATA_FORK, NULL);
+
+ error = xfs_dir2_block_read(NULL, dp, &bp);
if (error)
return error;
- ASSERT(bp != NULL);
/*
* Extract the byte offset we start at from the seek pointer.
* We'll skip entries before this.
@@ -637,14 +672,11 @@ xfs_dir2_block_lookup_int(
dp = args->dp;
tp = args->trans;
mp = dp->i_mount;
- /*
- * Read the buffer, return error if we can't get it.
- */
- error = xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &bp,
- XFS_DATA_FORK, NULL);
+
+ error = xfs_dir2_block_read(tp, dp, &bp);
if (error)
return error;
- ASSERT(bp != NULL);
+
hdr = bp->b_addr;
xfs_dir2_data_check(dp, bp);
btp = xfs_dir2_block_tail_p(mp, hdr);
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