return 0;
}
-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 */
-};
-
+/*
+ * Read a directory block and initiate readahead for blocks beyond that.
+ * We maintain a sliding readahead window of the remaining space in the
+ * buffer rounded up to the nearest block.
+ */
STATIC int
xfs_dir2_leaf_readbuf(
struct xfs_da_args *args,
size_t bufsize,
- struct xfs_dir2_leaf_map_info *mip,
- xfs_dir2_off_t *curoff,
- struct xfs_buf **bpp,
- bool trim_map)
+ xfs_dir2_off_t *cur_off,
+ xfs_dablk_t *ra_blk,
+ struct xfs_buf **bpp)
{
struct xfs_inode *dp = args->dp;
struct xfs_buf *bp = NULL;
- struct xfs_bmbt_irec *map = mip->map;
+ struct xfs_da_geometry *geo = args->geo;
+ struct xfs_ifork *ifp = XFS_IFORK_PTR(dp, XFS_DATA_FORK);
+ struct xfs_bmbt_irec map;
struct blk_plug plug;
+ xfs_dir2_off_t new_off;
+ xfs_dablk_t next_ra;
+ xfs_dablk_t map_off;
+ xfs_dablk_t last_da;
+ xfs_extnum_t idx;
+ int ra_want;
int error = 0;
- int length;
- int i;
- int j;
- struct xfs_da_geometry *geo = args->geo;
-
- /*
- * If the caller just finished processing a buffer, it will tell us
- * we need to trim that block out of the mapping now it is done.
- */
- if (trim_map) {
- mip->map_blocks -= geo->fsbcount;
- /*
- * Loop to get rid of the extents for the
- * directory block.
- */
- for (i = geo->fsbcount; 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 + geo->blksize, (1 << geo->fsblog)) - 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(geo, 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(geo, 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 (!(ifp->if_flags & XFS_IFEXTENTS)) {
+ error = xfs_iread_extents(args->trans, dp, XFS_DATA_FORK);
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(geo,
- 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;
+ goto out;
}
/*
- * No valid mappings, so no more data blocks.
+ * Look for mapped directory blocks at or above the current offset.
+ * Truncate down to the nearest directory block to start the scanning
+ * operation.
*/
- if (!mip->map_valid) {
- *curoff = xfs_dir2_da_to_byte(geo, mip->map_off);
+ last_da = xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET);
+ map_off = xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, *cur_off));
+ if (!xfs_iext_lookup_extent(dp, ifp, map_off, &idx, &map))
goto out;
- }
+ if (map.br_startoff >= last_da)
+ goto out;
+ xfs_trim_extent(&map, map_off, last_da - map_off);
- /*
- * Read the directory block starting at the first mapping.
- */
- mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff);
- error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
- map->br_blockcount >= geo->fsbcount ?
- XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) :
- -1, &bp);
- /*
- * Should just skip over the data block instead of giving up.
- */
+ /* Read the directory block of that first mapping. */
+ new_off = xfs_dir2_da_to_byte(geo, map.br_startoff);
+ if (new_off > *cur_off)
+ *cur_off = new_off;
+ error = xfs_dir3_data_read(args->trans, dp, map.br_startoff, -1, &bp);
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 -= geo->fsbcount;
+ goto out;
/*
- * Do we need more readahead?
- * Each loop tries to process 1 full dir blk; last may be partial.
+ * Start readahead for the next bufsize's worth of dir data blocks.
+ * We may have already issued readahead for some of that range;
+ * ra_blk tracks the last block we tried to read(ahead).
*/
+ ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
+ if (*ra_blk >= last_da)
+ goto out;
+ else if (*ra_blk == 0)
+ *ra_blk = map.br_startoff;
+ next_ra = map.br_startoff + geo->fsbcount;
+ if (next_ra >= last_da)
+ goto out_no_ra;
+ if (map.br_blockcount < geo->fsbcount &&
+ !xfs_iext_get_extent(ifp, ++idx, &map))
+ goto out_no_ra;
+ if (map.br_startoff >= last_da)
+ goto out_no_ra;
+ xfs_trim_extent(&map, next_ra, last_da - next_ra);
+
+ /* Start ra for each dir (not fs) block that has a mapping. */
blk_start_plug(&plug);
- for (mip->ra_index = mip->ra_offset = i = 0;
- mip->ra_want > mip->ra_current && i < mip->map_blocks;
- i += geo->fsbcount) {
- ASSERT(mip->ra_index < mip->map_valid);
- /*
- * Read-ahead a contiguous directory block.
- */
- if (i > mip->ra_current &&
- (map[mip->ra_index].br_blockcount - mip->ra_offset) >=
- geo->fsbcount) {
- xfs_dir3_data_readahead(dp,
- map[mip->ra_index].br_startoff + mip->ra_offset,
- XFS_FSB_TO_DADDR(dp->i_mount,
- map[mip->ra_index].br_startblock +
- mip->ra_offset));
- 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_dir3_data_readahead(dp,
- map[mip->ra_index].br_startoff +
- mip->ra_offset, -1);
- mip->ra_current = i;
- }
-
- /*
- * Advance offset through the mapping table, processing a full
- * dir block even if it is fragmented into several extents.
- * But stop if we have consumed all valid mappings, even if
- * it's not yet a full directory block.
- */
- for (j = 0;
- j < geo->fsbcount && mip->ra_index < mip->map_valid;
- j += length ) {
- /*
- * The rest of this extent but not more than a dir
- * block.
- */
- length = min_t(int, geo->fsbcount - j,
- map[mip->ra_index].br_blockcount -
- mip->ra_offset);
- 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++;
+ while (ra_want > 0) {
+ next_ra = roundup((xfs_dablk_t)map.br_startoff, geo->fsbcount);
+ while (ra_want > 0 &&
+ next_ra < map.br_startoff + map.br_blockcount) {
+ if (next_ra >= last_da) {
+ *ra_blk = last_da;
+ break;
+ }
+ if (next_ra > *ra_blk) {
+ xfs_dir3_data_readahead(dp, next_ra, -2);
+ *ra_blk = next_ra;
}
+ ra_want -= geo->fsbcount;
+ next_ra += geo->fsbcount;
+ }
+ if (!xfs_iext_get_extent(ifp, ++idx, &map)) {
+ *ra_blk = last_da;
+ break;
}
}
blk_finish_plug(&plug);
out:
*bpp = bp;
return error;
+out_no_ra:
+ *ra_blk = last_da;
+ goto out;
}
/*
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 length; /* temporary length value */
- int byteoff; /* offset in current block */
- xfs_dir2_off_t curoff; /* current overall offset */
- xfs_dir2_off_t newoff; /* new curoff after new blk */
char *ptr = NULL; /* pointer to current data */
- struct xfs_dir2_leaf_map_info *map_info;
struct xfs_da_geometry *geo = args->geo;
+ xfs_dablk_t rablk = 0; /* current readahead block */
+ xfs_dir2_off_t curoff; /* current overall offset */
+ int length; /* temporary length value */
+ int byteoff; /* offset in current block */
+ int lock_mode;
+ int error = 0; /* error return value */
/*
* If the offset is at or past the largest allowed value,
return 0;
/*
- * Set up to bmap a number of blocks based on the caller's
- * buffer size, the directory block size, and the filesystem
- * block size.
- */
- length = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
- map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
- (length * sizeof(struct xfs_bmbt_irec)),
- KM_SLEEP | KM_NOFS);
- map_info->map_size = length;
-
- /*
* Inside the loop we keep the main offset value as a byte offset
* in the directory file.
*/
curoff = xfs_dir2_dataptr_to_byte(ctx->pos);
/*
- * Force this conversion through db so we truncate the offset
- * down to get the start of the data block.
- */
- map_info->map_off = xfs_dir2_db_to_da(geo,
- xfs_dir2_byte_to_db(geo, curoff));
-
- /*
* Loop over directory entries until we reach the end offset.
* Get more blocks and readahead as necessary.
*/
* current buffer, need to get another one.
*/
if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
- int lock_mode;
- bool trim_map = false;
-
if (bp) {
- xfs_trans_brelse(NULL, bp);
+ xfs_trans_brelse(args->trans, bp);
bp = NULL;
- trim_map = true;
}
lock_mode = xfs_ilock_data_map_shared(dp);
- error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
- &curoff, &bp, trim_map);
+ error = xfs_dir2_leaf_readbuf(args, bufsize, &curoff,
+ &rablk, &bp);
xfs_iunlock(dp, lock_mode);
- if (error || !map_info->map_valid)
+ if (error || !bp)
break;
- /*
- * Having done a read, we need to set a new offset.
- */
- newoff = xfs_dir2_db_off_to_byte(geo,
- map_info->curdb, 0);
- /*
- * Start of the current block.
- */
- if (curoff < newoff)
- curoff = newoff;
- /*
- * Make sure we're in the right block.
- */
- else if (curoff > newoff)
- ASSERT(xfs_dir2_byte_to_db(geo, curoff) ==
- map_info->curdb);
hdr = bp->b_addr;
xfs_dir3_data_check(dp, bp);
/*
ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
else
ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
- kmem_free(map_info);
if (bp)
xfs_trans_brelse(NULL, bp);
return error;
projects / platform / kernel / linux-rpi3.git / commitdiff