From 3f165b334e51477d2b33ac1c81b39927514daab7 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 3 Oct 2016 09:11:48 -0700 Subject: [PATCH] xfs: convert unwritten status of reverse mappings for shared files Provide a function to convert an unwritten extent to a real one and vice versa when shared extents are possible. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/xfs/libxfs/xfs_rmap.c | 385 ++++++++++++++++++++++++++++++++++++++- fs/xfs/xfs_rmap_item.c | 3 + 2 files changed, 387 insertions(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c index bb5e2f840370..3a8cc7139912 100644 --- a/fs/xfs/libxfs/xfs_rmap.c +++ b/fs/xfs/libxfs/xfs_rmap.c @@ -1278,6 +1278,384 @@ done: return error; } +/* + * Convert an unwritten extent to a real extent or vice versa. If there is no + * possibility of overlapping extents, delegate to the simpler convert + * function. + */ +STATIC int +xfs_rmap_convert_shared( + struct xfs_btree_cur *cur, + xfs_agblock_t bno, + xfs_extlen_t len, + bool unwritten, + struct xfs_owner_info *oinfo) +{ + struct xfs_mount *mp = cur->bc_mp; + struct xfs_rmap_irec r[4]; /* neighbor extent entries */ + /* left is 0, right is 1, prev is 2 */ + /* new is 3 */ + uint64_t owner; + uint64_t offset; + uint64_t new_endoff; + unsigned int oldext; + unsigned int newext; + unsigned int flags = 0; + int i; + int state = 0; + int error; + + xfs_owner_info_unpack(oinfo, &owner, &offset, &flags); + ASSERT(!(XFS_RMAP_NON_INODE_OWNER(owner) || + (flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK)))); + oldext = unwritten ? XFS_RMAP_UNWRITTEN : 0; + new_endoff = offset + len; + trace_xfs_rmap_convert(mp, cur->bc_private.a.agno, bno, len, + unwritten, oinfo); + + /* + * For the initial lookup, look for and exact match or the left-adjacent + * record for our insertion point. This will also give us the record for + * start block contiguity tests. + */ + error = xfs_rmap_lookup_le_range(cur, bno, owner, offset, flags, + &PREV, &i); + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + + ASSERT(PREV.rm_offset <= offset); + ASSERT(PREV.rm_offset + PREV.rm_blockcount >= new_endoff); + ASSERT((PREV.rm_flags & XFS_RMAP_UNWRITTEN) == oldext); + newext = ~oldext & XFS_RMAP_UNWRITTEN; + + /* + * Set flags determining what part of the previous oldext allocation + * extent is being replaced by a newext allocation. + */ + if (PREV.rm_offset == offset) + state |= RMAP_LEFT_FILLING; + if (PREV.rm_offset + PREV.rm_blockcount == new_endoff) + state |= RMAP_RIGHT_FILLING; + + /* Is there a left record that abuts our range? */ + error = xfs_rmap_find_left_neighbor(cur, bno, owner, offset, newext, + &LEFT, &i); + if (error) + goto done; + if (i) { + state |= RMAP_LEFT_VALID; + XFS_WANT_CORRUPTED_GOTO(mp, + LEFT.rm_startblock + LEFT.rm_blockcount <= bno, + done); + if (xfs_rmap_is_mergeable(&LEFT, owner, newext)) + state |= RMAP_LEFT_CONTIG; + } + + /* Is there a right record that abuts our range? */ + error = xfs_rmap_lookup_eq(cur, bno + len, len, owner, offset + len, + newext, &i); + if (error) + goto done; + if (i) { + state |= RMAP_RIGHT_VALID; + error = xfs_rmap_get_rec(cur, &RIGHT, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + XFS_WANT_CORRUPTED_GOTO(mp, bno + len <= RIGHT.rm_startblock, + done); + trace_xfs_rmap_find_right_neighbor_result(cur->bc_mp, + cur->bc_private.a.agno, RIGHT.rm_startblock, + RIGHT.rm_blockcount, RIGHT.rm_owner, + RIGHT.rm_offset, RIGHT.rm_flags); + if (xfs_rmap_is_mergeable(&RIGHT, owner, newext)) + state |= RMAP_RIGHT_CONTIG; + } + + /* check that left + prev + right is not too long */ + if ((state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | + RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) == + (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | + RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG) && + (unsigned long)LEFT.rm_blockcount + len + + RIGHT.rm_blockcount > XFS_RMAP_LEN_MAX) + state &= ~RMAP_RIGHT_CONTIG; + + trace_xfs_rmap_convert_state(mp, cur->bc_private.a.agno, state, + _RET_IP_); + /* + * Switch out based on the FILLING and CONTIG state bits. + */ + switch (state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | + RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) { + case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | + RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG: + /* + * Setting all of a previous oldext extent to newext. + * The left and right neighbors are both contiguous with new. + */ + error = xfs_rmap_delete(cur, RIGHT.rm_startblock, + RIGHT.rm_blockcount, RIGHT.rm_owner, + RIGHT.rm_offset, RIGHT.rm_flags); + if (error) + goto done; + error = xfs_rmap_delete(cur, PREV.rm_startblock, + PREV.rm_blockcount, PREV.rm_owner, + PREV.rm_offset, PREV.rm_flags); + if (error) + goto done; + NEW = LEFT; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount += PREV.rm_blockcount + RIGHT.rm_blockcount; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG: + /* + * Setting all of a previous oldext extent to newext. + * The left neighbor is contiguous, the right is not. + */ + error = xfs_rmap_delete(cur, PREV.rm_startblock, + PREV.rm_blockcount, PREV.rm_owner, + PREV.rm_offset, PREV.rm_flags); + if (error) + goto done; + NEW = LEFT; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount += PREV.rm_blockcount; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG: + /* + * Setting all of a previous oldext extent to newext. + * The right neighbor is contiguous, the left is not. + */ + error = xfs_rmap_delete(cur, RIGHT.rm_startblock, + RIGHT.rm_blockcount, RIGHT.rm_owner, + RIGHT.rm_offset, RIGHT.rm_flags); + if (error) + goto done; + NEW = PREV; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount += RIGHT.rm_blockcount; + NEW.rm_flags = RIGHT.rm_flags; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING: + /* + * Setting all of a previous oldext extent to newext. + * Neither the left nor right neighbors are contiguous with + * the new one. + */ + NEW = PREV; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_flags = newext; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG: + /* + * Setting the first part of a previous oldext extent to newext. + * The left neighbor is contiguous. + */ + NEW = PREV; + error = xfs_rmap_delete(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + NEW.rm_offset += len; + NEW.rm_startblock += len; + NEW.rm_blockcount -= len; + error = xfs_rmap_insert(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + NEW = LEFT; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount += len; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING: + /* + * Setting the first part of a previous oldext extent to newext. + * The left neighbor is not contiguous. + */ + NEW = PREV; + error = xfs_rmap_delete(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + NEW.rm_offset += len; + NEW.rm_startblock += len; + NEW.rm_blockcount -= len; + error = xfs_rmap_insert(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + error = xfs_rmap_insert(cur, bno, len, owner, offset, newext); + if (error) + goto done; + break; + + case RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG: + /* + * Setting the last part of a previous oldext extent to newext. + * The right neighbor is contiguous with the new allocation. + */ + NEW = PREV; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount = offset - NEW.rm_offset; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + NEW = RIGHT; + error = xfs_rmap_delete(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + NEW.rm_offset = offset; + NEW.rm_startblock = bno; + NEW.rm_blockcount += len; + error = xfs_rmap_insert(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags); + if (error) + goto done; + break; + + case RMAP_RIGHT_FILLING: + /* + * Setting the last part of a previous oldext extent to newext. + * The right neighbor is not contiguous. + */ + NEW = PREV; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount -= len; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + error = xfs_rmap_insert(cur, bno, len, owner, offset, newext); + if (error) + goto done; + break; + + case 0: + /* + * Setting the middle part of a previous oldext extent to + * newext. Contiguity is impossible here. + * One extent becomes three extents. + */ + /* new right extent - oldext */ + NEW.rm_startblock = bno + len; + NEW.rm_owner = owner; + NEW.rm_offset = new_endoff; + NEW.rm_blockcount = PREV.rm_offset + PREV.rm_blockcount - + new_endoff; + NEW.rm_flags = PREV.rm_flags; + error = xfs_rmap_insert(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, NEW.rm_offset, + NEW.rm_flags); + if (error) + goto done; + /* new left extent - oldext */ + NEW = PREV; + error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, + NEW.rm_offset, NEW.rm_flags, &i); + if (error) + goto done; + XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done); + NEW.rm_blockcount = offset - NEW.rm_offset; + error = xfs_rmap_update(cur, &NEW); + if (error) + goto done; + /* new middle extent - newext */ + NEW.rm_startblock = bno; + NEW.rm_blockcount = len; + NEW.rm_owner = owner; + NEW.rm_offset = offset; + NEW.rm_flags = newext; + error = xfs_rmap_insert(cur, NEW.rm_startblock, + NEW.rm_blockcount, NEW.rm_owner, NEW.rm_offset, + NEW.rm_flags); + if (error) + goto done; + break; + + case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG: + case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG: + case RMAP_LEFT_FILLING | RMAP_RIGHT_CONTIG: + case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG: + case RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG: + case RMAP_LEFT_CONTIG: + case RMAP_RIGHT_CONTIG: + /* + * These cases are all impossible. + */ + ASSERT(0); + } + + trace_xfs_rmap_convert_done(mp, cur->bc_private.a.agno, bno, len, + unwritten, oinfo); +done: + if (error) + trace_xfs_rmap_convert_error(cur->bc_mp, + cur->bc_private.a.agno, error, _RET_IP_); + return error; +} + #undef NEW #undef LEFT #undef RIGHT @@ -1754,6 +2132,10 @@ xfs_rmap_finish_one( error = xfs_rmap_convert(rcur, bno, blockcount, !unwritten, &oinfo); break; + case XFS_RMAP_CONVERT_SHARED: + error = xfs_rmap_convert_shared(rcur, bno, blockcount, + !unwritten, &oinfo); + break; default: ASSERT(0); error = -EFSCORRUPTED; @@ -1857,7 +2239,8 @@ xfs_rmap_convert_extent( if (!xfs_rmap_update_is_needed(mp, whichfork)) return 0; - return __xfs_rmap_add(mp, dfops, XFS_RMAP_CONVERT, ip->i_ino, + return __xfs_rmap_add(mp, dfops, xfs_is_reflink_inode(ip) ? + XFS_RMAP_CONVERT_SHARED : XFS_RMAP_CONVERT, ip->i_ino, whichfork, PREV); } diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c index 3b8742e48815..73c827831551 100644 --- a/fs/xfs/xfs_rmap_item.c +++ b/fs/xfs/xfs_rmap_item.c @@ -496,6 +496,9 @@ xfs_rui_recover( case XFS_RMAP_EXTENT_CONVERT: type = XFS_RMAP_CONVERT; break; + case XFS_RMAP_EXTENT_CONVERT_SHARED: + type = XFS_RMAP_CONVERT_SHARED; + break; case XFS_RMAP_EXTENT_ALLOC: type = XFS_RMAP_ALLOC; break; -- 2.20.1