diff options
| -rw-r--r-- | fs/xfs/xfs_bmap.c | 181 |
1 files changed, 107 insertions, 74 deletions
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c index 05d38adbb85e..59f63949d3bc 100644 --- a/fs/xfs/xfs_bmap.c +++ b/fs/xfs/xfs_bmap.c @@ -4249,6 +4249,107 @@ xfs_bmap_validate_ret( /* + * Trim the returned map to the required bounds + */ +STATIC void +xfs_bmapi_trim_map( + struct xfs_bmbt_irec *mval, + struct xfs_bmbt_irec *got, + xfs_fileoff_t *bno, + xfs_filblks_t len, + xfs_fileoff_t obno, + xfs_fileoff_t end, + int n, + int flags) +{ + if ((flags & XFS_BMAPI_ENTIRE) || + got->br_startoff + got->br_blockcount <= obno) { + *mval = *got; + if (isnullstartblock(got->br_startblock)) + mval->br_startblock = DELAYSTARTBLOCK; + return; + } + + if (obno > *bno) + *bno = obno; + ASSERT((*bno >= obno) || (n == 0)); + ASSERT(*bno < end); + mval->br_startoff = *bno; + if (isnullstartblock(got->br_startblock)) + mval->br_startblock = DELAYSTARTBLOCK; + else + mval->br_startblock = got->br_startblock + + (*bno - got->br_startoff); + /* + * Return the minimum of what we got and what we asked for for + * the length. We can use the len variable here because it is + * modified below and we could have been there before coming + * here if the first part of the allocation didn't overlap what + * was asked for. + */ + mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno, + got->br_blockcount - (*bno - got->br_startoff)); + mval->br_state = got->br_state; + ASSERT(mval->br_blockcount <= len); + return; +} + +/* + * Update and validate the extent map to return + */ +STATIC void +xfs_bmapi_update_map( + struct xfs_bmbt_irec **map, + xfs_fileoff_t *bno, + xfs_filblks_t *len, + xfs_fileoff_t obno, + xfs_fileoff_t end, + int *n, + int flags) +{ + xfs_bmbt_irec_t *mval = *map; + + ASSERT((flags & XFS_BMAPI_ENTIRE) || + ((mval->br_startoff + mval->br_blockcount) <= end)); + ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) || + (mval->br_startoff < obno)); + + *bno = mval->br_startoff + mval->br_blockcount; + *len = end - *bno; + if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) { + /* update previous map with new information */ + ASSERT(mval->br_startblock == mval[-1].br_startblock); + ASSERT(mval->br_blockcount > mval[-1].br_blockcount); + ASSERT(mval->br_state == mval[-1].br_state); + mval[-1].br_blockcount = mval->br_blockcount; + mval[-1].br_state = mval->br_state; + } else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK && + mval[-1].br_startblock != DELAYSTARTBLOCK && + mval[-1].br_startblock != HOLESTARTBLOCK && + mval->br_startblock == mval[-1].br_startblock + + mval[-1].br_blockcount && + ((flags & XFS_BMAPI_IGSTATE) || + mval[-1].br_state == mval->br_state)) { + ASSERT(mval->br_startoff == + mval[-1].br_startoff + mval[-1].br_blockcount); + mval[-1].br_blockcount += mval->br_blockcount; + } else if (*n > 0 && + mval->br_startblock == DELAYSTARTBLOCK && + mval[-1].br_startblock == DELAYSTARTBLOCK && + mval->br_startoff == + mval[-1].br_startoff + mval[-1].br_blockcount) { + mval[-1].br_blockcount += mval->br_blockcount; + mval[-1].br_state = mval->br_state; + } else if (!((*n == 0) && + ((mval->br_startoff + mval->br_blockcount) <= + obno))) { + mval++; + (*n)++; + } + *map = mval; +} + +/* * 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) @@ -4650,44 +4751,9 @@ xfs_bmapi( n++; continue; } - /* - * Then deal with the allocated space we found. - */ - ASSERT(ep != NULL); - if (!(flags & XFS_BMAPI_ENTIRE) && - (got.br_startoff + got.br_blockcount > obno)) { - if (obno > bno) - bno = obno; - ASSERT((bno >= obno) || (n == 0)); - ASSERT(bno < end); - mval->br_startoff = bno; - if (isnullstartblock(got.br_startblock)) { - ASSERT(!wr || (flags & XFS_BMAPI_DELAY)); - mval->br_startblock = DELAYSTARTBLOCK; - } else - mval->br_startblock = - got.br_startblock + - (bno - got.br_startoff); - /* - * Return the minimum of what we got and what we - * asked for for the length. We can use the len - * variable here because it is modified below - * and we could have been there before coming - * here if the first part of the allocation - * didn't overlap what was asked for. - */ - mval->br_blockcount = - XFS_FILBLKS_MIN(end - bno, got.br_blockcount - - (bno - got.br_startoff)); - mval->br_state = got.br_state; - ASSERT(mval->br_blockcount <= len); - } else { - *mval = got; - if (isnullstartblock(mval->br_startblock)) { - ASSERT(!wr || (flags & XFS_BMAPI_DELAY)); - mval->br_startblock = DELAYSTARTBLOCK; - } - } + + /* Deal with the allocated space we found. */ + xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags); /* * Check if writing previously allocated but @@ -4730,42 +4796,9 @@ xfs_bmapi( continue; } - ASSERT((flags & XFS_BMAPI_ENTIRE) || - ((mval->br_startoff + mval->br_blockcount) <= end)); - ASSERT((flags & XFS_BMAPI_ENTIRE) || - (mval->br_blockcount <= len) || - (mval->br_startoff < obno)); - bno = mval->br_startoff + mval->br_blockcount; - len = end - bno; - if (n > 0 && mval->br_startoff == mval[-1].br_startoff) { - ASSERT(mval->br_startblock == mval[-1].br_startblock); - ASSERT(mval->br_blockcount > mval[-1].br_blockcount); - ASSERT(mval->br_state == mval[-1].br_state); - mval[-1].br_blockcount = mval->br_blockcount; - mval[-1].br_state = mval->br_state; - } else if (n > 0 && mval->br_startblock != DELAYSTARTBLOCK && - mval[-1].br_startblock != DELAYSTARTBLOCK && - mval[-1].br_startblock != HOLESTARTBLOCK && - mval->br_startblock == - mval[-1].br_startblock + mval[-1].br_blockcount && - ((flags & XFS_BMAPI_IGSTATE) || - mval[-1].br_state == mval->br_state)) { - ASSERT(mval->br_startoff == - mval[-1].br_startoff + mval[-1].br_blockcount); - mval[-1].br_blockcount += mval->br_blockcount; - } else if (n > 0 && - mval->br_startblock == DELAYSTARTBLOCK && - mval[-1].br_startblock == DELAYSTARTBLOCK && - mval->br_startoff == - mval[-1].br_startoff + mval[-1].br_blockcount) { - mval[-1].br_blockcount += mval->br_blockcount; - mval[-1].br_state = mval->br_state; - } else if (!((n == 0) && - ((mval->br_startoff + mval->br_blockcount) <= - obno))) { - mval++; - n++; - } + /* update the extent map to return */ + xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags); + /* * If we're done, stop now. Stop when we've allocated * XFS_BMAP_MAX_NMAP extents no matter what. Otherwise |