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path: root/fs/xfs/xfs_dir2_leaf.c
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Diffstat (limited to 'fs/xfs/xfs_dir2_leaf.c')
-rw-r--r--fs/xfs/xfs_dir2_leaf.c434
1 files changed, 232 insertions, 202 deletions
diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 69accf6cbc46..0b296253bd01 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -759,6 +759,218 @@ xfs_dir2_leaf_compact_x1(
*highstalep = highstale;
}
+struct xfs_dir2_leaf_map_info {
+ xfs_extlen_t map_blocks; /* number of fsbs in map */
+ xfs_dablk_t map_off; /* last mapped file offset */
+ int map_size; /* total entries in *map */
+ int map_valid; /* valid entries in *map */
+ int nmap; /* mappings to ask xfs_bmapi */
+ xfs_dir2_db_t curdb; /* db for current block */
+ int ra_current; /* number of read-ahead blks */
+ int ra_index; /* *map index for read-ahead */
+ int ra_offset; /* map entry offset for ra */
+ int ra_want; /* readahead count wanted */
+ struct xfs_bmbt_irec map[]; /* map vector for blocks */
+};
+
+STATIC int
+xfs_dir2_leaf_readbuf(
+ struct xfs_inode *dp,
+ size_t bufsize,
+ struct xfs_dir2_leaf_map_info *mip,
+ xfs_dir2_off_t *curoff,
+ struct xfs_buf **bpp)
+{
+ struct xfs_mount *mp = dp->i_mount;
+ struct xfs_buf *bp = *bpp;
+ struct xfs_bmbt_irec *map = mip->map;
+ int error = 0;
+ int length;
+ int i;
+ int j;
+
+ /*
+ * If we have a buffer, we need to release it and
+ * take it out of the mapping.
+ */
+
+ if (bp) {
+ xfs_trans_brelse(NULL, bp);
+ bp = NULL;
+ mip->map_blocks -= mp->m_dirblkfsbs;
+ /*
+ * Loop to get rid of the extents for the
+ * directory block.
+ */
+ for (i = mp->m_dirblkfsbs; i > 0; ) {
+ j = min_t(int, map->br_blockcount, i);
+ map->br_blockcount -= j;
+ map->br_startblock += j;
+ map->br_startoff += j;
+ /*
+ * If mapping is done, pitch it from
+ * the table.
+ */
+ if (!map->br_blockcount && --mip->map_valid)
+ memmove(&map[0], &map[1],
+ sizeof(map[0]) * mip->map_valid);
+ i -= j;
+ }
+ }
+
+ /*
+ * Recalculate the readahead blocks wanted.
+ */
+ mip->ra_want = howmany(bufsize + mp->m_dirblksize,
+ mp->m_sb.sb_blocksize) - 1;
+ ASSERT(mip->ra_want >= 0);
+
+ /*
+ * If we don't have as many as we want, and we haven't
+ * run out of data blocks, get some more mappings.
+ */
+ if (1 + mip->ra_want > mip->map_blocks &&
+ mip->map_off < xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
+ /*
+ * Get more bmaps, fill in after the ones
+ * we already have in the table.
+ */
+ mip->nmap = mip->map_size - mip->map_valid;
+ error = xfs_bmapi_read(dp, mip->map_off,
+ xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET) -
+ mip->map_off,
+ &map[mip->map_valid], &mip->nmap, 0);
+
+ /*
+ * Don't know if we should ignore this or try to return an
+ * error. The trouble with returning errors is that readdir
+ * will just stop without actually passing the error through.
+ */
+ if (error)
+ goto out; /* XXX */
+
+ /*
+ * If we got all the mappings we asked for, set the final map
+ * offset based on the last bmap value received. Otherwise,
+ * we've reached the end.
+ */
+ if (mip->nmap == mip->map_size - mip->map_valid) {
+ i = mip->map_valid + mip->nmap - 1;
+ mip->map_off = map[i].br_startoff + map[i].br_blockcount;
+ } else
+ mip->map_off = xfs_dir2_byte_to_da(mp,
+ XFS_DIR2_LEAF_OFFSET);
+
+ /*
+ * Look for holes in the mapping, and eliminate them. Count up
+ * the valid blocks.
+ */
+ for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
+ if (map[i].br_startblock == HOLESTARTBLOCK) {
+ mip->nmap--;
+ length = mip->map_valid + mip->nmap - i;
+ if (length)
+ memmove(&map[i], &map[i + 1],
+ sizeof(map[i]) * length);
+ } else {
+ mip->map_blocks += map[i].br_blockcount;
+ i++;
+ }
+ }
+ mip->map_valid += mip->nmap;
+ }
+
+ /*
+ * No valid mappings, so no more data blocks.
+ */
+ if (!mip->map_valid) {
+ *curoff = xfs_dir2_da_to_byte(mp, mip->map_off);
+ goto out;
+ }
+
+ /*
+ * Read the directory block starting at the first mapping.
+ */
+ mip->curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
+ error = xfs_da_read_buf(NULL, dp, map->br_startoff,
+ map->br_blockcount >= mp->m_dirblkfsbs ?
+ XFS_FSB_TO_DADDR(mp, map->br_startblock) : -1,
+ &bp, XFS_DATA_FORK);
+
+ /*
+ * Should just skip over the data block instead of giving up.
+ */
+ if (error)
+ goto out; /* XXX */
+
+ /*
+ * Adjust the current amount of read-ahead: we just read a block that
+ * was previously ra.
+ */
+ if (mip->ra_current)
+ mip->ra_current -= mp->m_dirblkfsbs;
+
+ /*
+ * Do we need more readahead?
+ */
+ for (mip->ra_index = mip->ra_offset = i = 0;
+ mip->ra_want > mip->ra_current && i < mip->map_blocks;
+ i += mp->m_dirblkfsbs) {
+ ASSERT(mip->ra_index < mip->map_valid);
+ /*
+ * Read-ahead a contiguous directory block.
+ */
+ if (i > mip->ra_current &&
+ map[mip->ra_index].br_blockcount >= mp->m_dirblkfsbs) {
+ xfs_buf_readahead(mp->m_ddev_targp,
+ XFS_FSB_TO_DADDR(mp,
+ map[mip->ra_index].br_startblock +
+ mip->ra_offset),
+ (int)BTOBB(mp->m_dirblksize));
+ mip->ra_current = i;
+ }
+
+ /*
+ * Read-ahead a non-contiguous directory block. This doesn't
+ * use our mapping, but this is a very rare case.
+ */
+ else if (i > mip->ra_current) {
+ xfs_da_reada_buf(NULL, dp,
+ map[mip->ra_index].br_startoff +
+ mip->ra_offset,
+ XFS_DATA_FORK);
+ mip->ra_current = i;
+ }
+
+ /*
+ * Advance offset through the mapping table.
+ */
+ for (j = 0; j < mp->m_dirblkfsbs; j++) {
+ /*
+ * The rest of this extent but not more than a dir
+ * block.
+ */
+ length = min_t(int, mp->m_dirblkfsbs,
+ map[mip->ra_index].br_blockcount -
+ mip->ra_offset);
+ j += length;
+ mip->ra_offset += length;
+
+ /*
+ * Advance to the next mapping if this one is used up.
+ */
+ if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
+ mip->ra_offset = 0;
+ mip->ra_index++;
+ }
+ }
+ }
+
+out:
+ *bpp = bp;
+ return error;
+}
+
/*
* Getdents (readdir) for leaf and node directories.
* This reads the data blocks only, so is the same for both forms.
@@ -771,30 +983,18 @@ xfs_dir2_leaf_getdents(
xfs_off_t *offset,
filldir_t filldir)
{
- struct xfs_buf *bp; /* data block buffer */
- int byteoff; /* offset in current block */
- xfs_dir2_db_t curdb; /* db for current block */
- xfs_dir2_off_t curoff; /* current overall offset */
+ struct xfs_buf *bp = NULL; /* data block buffer */
xfs_dir2_data_hdr_t *hdr; /* data block header */
xfs_dir2_data_entry_t *dep; /* data entry */
xfs_dir2_data_unused_t *dup; /* unused entry */
int error = 0; /* error return value */
- int i; /* temporary loop index */
- int j; /* temporary loop index */
int length; /* temporary length value */
- xfs_bmbt_irec_t *map; /* map vector for blocks */
- xfs_extlen_t map_blocks; /* number of fsbs in map */
- xfs_dablk_t map_off; /* last mapped file offset */
- int map_size; /* total entries in *map */
- int map_valid; /* valid entries in *map */
xfs_mount_t *mp; /* filesystem mount point */
+ int byteoff; /* offset in current block */
+ xfs_dir2_off_t curoff; /* current overall offset */
xfs_dir2_off_t newoff; /* new curoff after new blk */
- int nmap; /* mappings to ask xfs_bmapi */
char *ptr = NULL; /* pointer to current data */
- int ra_current; /* number of read-ahead blks */
- int ra_index; /* *map index for read-ahead */
- int ra_offset; /* map entry offset for ra */
- int ra_want; /* readahead count wanted */
+ struct xfs_dir2_leaf_map_info *map_info;
/*
* If the offset is at or past the largest allowed value,
@@ -810,10 +1010,12 @@ xfs_dir2_leaf_getdents(
* buffer size, the directory block size, and the filesystem
* block size.
*/
- map_size = howmany(bufsize + mp->m_dirblksize, mp->m_sb.sb_blocksize);
- map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
- map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
- bp = NULL;
+ length = howmany(bufsize + mp->m_dirblksize,
+ mp->m_sb.sb_blocksize);
+ map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
+ (length * sizeof(struct xfs_bmbt_irec)),
+ KM_SLEEP);
+ map_info->map_size = length;
/*
* Inside the loop we keep the main offset value as a byte offset
@@ -825,7 +1027,9 @@ xfs_dir2_leaf_getdents(
* Force this conversion through db so we truncate the offset
* down to get the start of the data block.
*/
- map_off = xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, curoff));
+ map_info->map_off = xfs_dir2_db_to_da(mp,
+ xfs_dir2_byte_to_db(mp, curoff));
+
/*
* Loop over directory entries until we reach the end offset.
* Get more blocks and readahead as necessary.
@@ -836,190 +1040,16 @@ xfs_dir2_leaf_getdents(
* current buffer, need to get another one.
*/
if (!bp || ptr >= (char *)bp->b_addr + mp->m_dirblksize) {
- /*
- * If we have a buffer, we need to release it and
- * take it out of the mapping.
- */
- if (bp) {
- xfs_trans_brelse(NULL, bp);
- bp = NULL;
- map_blocks -= mp->m_dirblkfsbs;
- /*
- * Loop to get rid of the extents for the
- * directory block.
- */
- for (i = mp->m_dirblkfsbs; i > 0; ) {
- j = MIN((int)map->br_blockcount, i);
- map->br_blockcount -= j;
- map->br_startblock += j;
- map->br_startoff += j;
- /*
- * If mapping is done, pitch it from
- * the table.
- */
- if (!map->br_blockcount && --map_valid)
- memmove(&map[0], &map[1],
- sizeof(map[0]) *
- map_valid);
- i -= j;
- }
- }
- /*
- * Recalculate the readahead blocks wanted.
- */
- ra_want = howmany(bufsize + mp->m_dirblksize,
- mp->m_sb.sb_blocksize) - 1;
- ASSERT(ra_want >= 0);
- /*
- * If we don't have as many as we want, and we haven't
- * run out of data blocks, get some more mappings.
- */
- if (1 + ra_want > map_blocks &&
- map_off <
- xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
- /*
- * Get more bmaps, fill in after the ones
- * we already have in the table.
- */
- nmap = map_size - map_valid;
- error = xfs_bmapi_read(dp, map_off,
- xfs_dir2_byte_to_da(mp,
- XFS_DIR2_LEAF_OFFSET) - map_off,
- &map[map_valid], &nmap, 0);
- /*
- * Don't know if we should ignore this or
- * try to return an error.
- * The trouble with returning errors
- * is that readdir will just stop without
- * actually passing the error through.
- */
- if (error)
- break; /* XXX */
- /*
- * If we got all the mappings we asked for,
- * set the final map offset based on the
- * last bmap value received.
- * Otherwise, we've reached the end.
- */
- if (nmap == map_size - map_valid)
- map_off =
- map[map_valid + nmap - 1].br_startoff +
- map[map_valid + nmap - 1].br_blockcount;
- else
- map_off =
- xfs_dir2_byte_to_da(mp,
- XFS_DIR2_LEAF_OFFSET);
- /*
- * Look for holes in the mapping, and
- * eliminate them. Count up the valid blocks.
- */
- for (i = map_valid; i < map_valid + nmap; ) {
- if (map[i].br_startblock ==
- HOLESTARTBLOCK) {
- nmap--;
- length = map_valid + nmap - i;
- if (length)
- memmove(&map[i],
- &map[i + 1],
- sizeof(map[i]) *
- length);
- } else {
- map_blocks +=
- map[i].br_blockcount;
- i++;
- }
- }
- map_valid += nmap;
- }
- /*
- * No valid mappings, so no more data blocks.
- */
- if (!map_valid) {
- curoff = xfs_dir2_da_to_byte(mp, map_off);
+ error = xfs_dir2_leaf_readbuf(dp, bufsize, map_info,
+ &curoff, &bp);
+ if (error || !map_info->map_valid)
break;
- }
- /*
- * Read the directory block starting at the first
- * mapping.
- */
- curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
- error = xfs_da_read_buf(NULL, dp, map->br_startoff,
- map->br_blockcount >= mp->m_dirblkfsbs ?
- XFS_FSB_TO_DADDR(mp, map->br_startblock) :
- -1,
- &bp, XFS_DATA_FORK);
- /*
- * Should just skip over the data block instead
- * of giving up.
- */
- if (error)
- break; /* XXX */
- /*
- * Adjust the current amount of read-ahead: we just
- * read a block that was previously ra.
- */
- if (ra_current)
- ra_current -= mp->m_dirblkfsbs;
- /*
- * Do we need more readahead?
- */
- for (ra_index = ra_offset = i = 0;
- ra_want > ra_current && i < map_blocks;
- i += mp->m_dirblkfsbs) {
- ASSERT(ra_index < map_valid);
- /*
- * Read-ahead a contiguous directory block.
- */
- if (i > ra_current &&
- map[ra_index].br_blockcount >=
- mp->m_dirblkfsbs) {
- xfs_buf_readahead(mp->m_ddev_targp,
- XFS_FSB_TO_DADDR(mp,
- map[ra_index].br_startblock +
- ra_offset),
- (int)BTOBB(mp->m_dirblksize));
- ra_current = i;
- }
- /*
- * Read-ahead a non-contiguous directory block.
- * This doesn't use our mapping, but this
- * is a very rare case.
- */
- else if (i > ra_current) {
- (void)xfs_da_reada_buf(NULL, dp,
- map[ra_index].br_startoff +
- ra_offset, XFS_DATA_FORK);
- ra_current = i;
- }
- /*
- * Advance offset through the mapping table.
- */
- for (j = 0; j < mp->m_dirblkfsbs; j++) {
- /*
- * The rest of this extent but not
- * more than a dir block.
- */
- length = MIN(mp->m_dirblkfsbs,
- (int)(map[ra_index].br_blockcount -
- ra_offset));
- j += length;
- ra_offset += length;
- /*
- * Advance to the next mapping if
- * this one is used up.
- */
- if (ra_offset ==
- map[ra_index].br_blockcount) {
- ra_offset = 0;
- ra_index++;
- }
- }
- }
+
/*
* Having done a read, we need to set a new offset.
*/
- newoff = xfs_dir2_db_off_to_byte(mp, curdb, 0);
+ newoff = xfs_dir2_db_off_to_byte(mp, map_info->curdb, 0);
/*
* Start of the current block.
*/
@@ -1030,7 +1060,7 @@ xfs_dir2_leaf_getdents(
*/
else if (curoff > newoff)
ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
- curdb);
+ map_info->curdb);
hdr = bp->b_addr;
xfs_dir2_data_check(dp, bp);
/*
@@ -1113,7 +1143,7 @@ xfs_dir2_leaf_getdents(
*offset = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
else
*offset = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
- kmem_free(map);
+ kmem_free(map_info);
if (bp)
xfs_trans_brelse(NULL, bp);
return error;