*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;
- struct blk_plug plug;
- 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_dir3_data_read(NULL, dp, map->br_startoff,
- map->br_blockcount >= mp->m_dirblkfsbs ?
- XFS_FSB_TO_DADDR(mp, map->br_startblock) : -1, &bp);
-
- /*
- * 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?
- */
- blk_start_plug(&plug);
- 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_dir3_data_readahead(NULL, dp,
- map[mip->ra_index].br_startoff + mip->ra_offset,
- XFS_FSB_TO_DADDR(mp,
- 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(NULL, dp,
- map[mip->ra_index].br_startoff +
- mip->ra_offset, -1);
- 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++;
- }
- }
- }
- blk_finish_plug(&plug);
-
-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.
- */
-int /* error */
-xfs_dir2_leaf_getdents(
- xfs_inode_t *dp, /* incore directory inode */
- struct dir_context *ctx,
- size_t bufsize)
-{
- 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 length; /* temporary length value */
- 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 */
- char *ptr = NULL; /* pointer to current data */
- struct xfs_dir2_leaf_map_info *map_info;
-
- /*
- * If the offset is at or past the largest allowed value,
- * give up right away.
- */
- if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
- return 0;
-
- mp = dp->i_mount;
-
- /*
- * 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 + 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 | 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(mp, 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(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.
- */
- while (curoff < XFS_DIR2_LEAF_OFFSET) {
- /*
- * If we have no buffer, or we're off the end of the
- * current buffer, need to get another one.
- */
- if (!bp || ptr >= (char *)bp->b_addr + mp->m_dirblksize) {
-
- error = xfs_dir2_leaf_readbuf(dp, bufsize, map_info,
- &curoff, &bp);
- if (error || !map_info->map_valid)
- break;
-
- /*
- * Having done a read, we need to set a new offset.
- */
- newoff = xfs_dir2_db_off_to_byte(mp, 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(mp, curoff) ==
- map_info->curdb);
- hdr = bp->b_addr;
- xfs_dir3_data_check(dp, bp);
- /*
- * Find our position in the block.
- */
- ptr = (char *)xfs_dir3_data_entry_p(hdr);
- byteoff = xfs_dir2_byte_to_off(mp, curoff);
- /*
- * Skip past the header.
- */
- if (byteoff == 0)
- curoff += xfs_dir3_data_entry_offset(hdr);
- /*
- * Skip past entries until we reach our offset.
- */
- else {
- while ((char *)ptr - (char *)hdr < byteoff) {
- dup = (xfs_dir2_data_unused_t *)ptr;
-
- if (be16_to_cpu(dup->freetag)
- == XFS_DIR2_DATA_FREE_TAG) {
-
- length = be16_to_cpu(dup->length);
- ptr += length;
- continue;
- }
- dep = (xfs_dir2_data_entry_t *)ptr;
- length =
- xfs_dir2_data_entsize(dep->namelen);
- ptr += length;
- }
- /*
- * Now set our real offset.
- */
- curoff =
- xfs_dir2_db_off_to_byte(mp,
- xfs_dir2_byte_to_db(mp, curoff),
- (char *)ptr - (char *)hdr);
- if (ptr >= (char *)hdr + mp->m_dirblksize) {
- continue;
- }
- }
- }
- /*
- * We have a pointer to an entry.
- * Is it a live one?
- */
- dup = (xfs_dir2_data_unused_t *)ptr;
- /*
- * No, it's unused, skip over it.
- */
- if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
- length = be16_to_cpu(dup->length);
- ptr += length;
- curoff += length;
- continue;
- }
-
- dep = (xfs_dir2_data_entry_t *)ptr;
- length = xfs_dir2_data_entsize(dep->namelen);
-
- ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
- if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
- be64_to_cpu(dep->inumber), DT_UNKNOWN))
- break;
-
- /*
- * Advance to next entry in the block.
- */
- ptr += length;
- curoff += length;
- /* bufsize may have just been a guess; don't go negative */
- bufsize = bufsize > length ? bufsize - length : 0;
- }
-
- /*
- * All done. Set output offset value to current offset.
- */
- if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
- ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
- else
- ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
- kmem_free(map_info);
- if (bp)
- xfs_trans_brelse(NULL, bp);
- return error;
-}
-
-
/*
* Log the bests entries indicated from a leaf1 block.
*/
projects / deliverable / linux.git / blobdiff