diff options
Diffstat (limited to 'fs/xfs/xfs_bmap.c')
-rw-r--r-- | fs/xfs/xfs_bmap.c | 104 |
1 files changed, 97 insertions, 7 deletions
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c index 59f63949d3bc..fc5acf0b921e 100644 --- a/fs/xfs/xfs_bmap.c +++ b/fs/xfs/xfs_bmap.c @@ -4350,6 +4350,98 @@ xfs_bmapi_update_map( } /* + * Map file blocks to filesystem blocks without allocation. + */ +int +xfs_bmapi_read( + struct xfs_inode *ip, + xfs_fileoff_t bno, + xfs_filblks_t len, + struct xfs_bmbt_irec *mval, + int *nmap, + int flags) +{ + struct xfs_mount *mp = ip->i_mount; + struct xfs_ifork *ifp; + struct xfs_bmbt_irec got; + struct xfs_bmbt_irec prev; + xfs_fileoff_t obno; + xfs_fileoff_t end; + xfs_extnum_t lastx; + int error; + int eof; + int n = 0; + int whichfork = (flags & XFS_BMAPI_ATTRFORK) ? + XFS_ATTR_FORK : XFS_DATA_FORK; + + ASSERT(*nmap >= 1); + ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK|XFS_BMAPI_ENTIRE| + XFS_BMAPI_IGSTATE))); + + if (unlikely(XFS_TEST_ERROR( + (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS && + XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE), + mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) { + XFS_ERROR_REPORT("xfs_bmapi_read", XFS_ERRLEVEL_LOW, mp); + return XFS_ERROR(EFSCORRUPTED); + } + + if (XFS_FORCED_SHUTDOWN(mp)) + return XFS_ERROR(EIO); + + XFS_STATS_INC(xs_blk_mapr); + + ifp = XFS_IFORK_PTR(ip, whichfork); + ASSERT(ifp->if_ext_max == + XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t)); + + if (!(ifp->if_flags & XFS_IFEXTENTS)) { + error = xfs_iread_extents(NULL, ip, whichfork); + if (error) + return error; + } + + xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got, &prev); + end = bno + len; + obno = bno; + + while (bno < end && n < *nmap) { + /* Reading past eof, act as though there's a hole up to end. */ + if (eof) + got.br_startoff = end; + if (got.br_startoff > bno) { + /* Reading in a hole. */ + mval->br_startoff = bno; + mval->br_startblock = HOLESTARTBLOCK; + mval->br_blockcount = + XFS_FILBLKS_MIN(len, got.br_startoff - bno); + mval->br_state = XFS_EXT_NORM; + bno += mval->br_blockcount; + len -= mval->br_blockcount; + mval++; + n++; + continue; + } + + /* set up the extent map to return. */ + xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags); + xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags); + + /* If we're done, stop now. */ + if (bno >= end || n >= *nmap) + break; + + /* Else go on to the next record. */ + if (++lastx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) + xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx), &got); + else + eof = 1; + } + *nmap = n; + return 0; +} + +/* * Map file blocks to filesystem blocks. * File range is given by the bno/len pair. * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set) @@ -5490,10 +5582,9 @@ xfs_getbmap( do { nmap = (nexleft > subnex) ? subnex : nexleft; - error = xfs_bmapi(NULL, ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset), - XFS_BB_TO_FSB(mp, bmv->bmv_length), - bmapi_flags, NULL, 0, map, &nmap, - NULL); + error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset), + XFS_BB_TO_FSB(mp, bmv->bmv_length), + map, &nmap, bmapi_flags); if (error) goto out_free_map; ASSERT(nmap <= subnex); @@ -6084,9 +6175,8 @@ xfs_bmap_punch_delalloc_range( * trying to remove a real extent (which requires a * transaction) or a hole, which is probably a bad idea... */ - error = xfs_bmapi(NULL, ip, start_fsb, 1, - XFS_BMAPI_ENTIRE, NULL, 0, &imap, - &nimaps, NULL); + error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps, + XFS_BMAPI_ENTIRE); if (error) { /* something screwed, just bail */ |