diff options
Diffstat (limited to 'fs/xfs/xfs_reflink.c')
| -rw-r--r-- | fs/xfs/xfs_reflink.c | 684 |
1 files changed, 257 insertions, 427 deletions
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index a279b4e7f5fe..4a84c5ea266d 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -82,11 +82,22 @@ * mappings are a reservation against the free space in the filesystem; * adjacent mappings can also be combined into fewer larger mappings. * + * As an optimization, the CoW extent size hint (cowextsz) creates + * outsized aligned delalloc reservations in the hope of landing out of + * order nearby CoW writes in a single extent on disk, thereby reducing + * fragmentation and improving future performance. + * + * D: --RRRRRRSSSRRRRRRRR--- (data fork) + * C: ------DDDDDDD--------- (CoW fork) + * * When dirty pages are being written out (typically in writepage), the - * delalloc reservations are converted into real mappings by allocating - * blocks and replacing the delalloc mapping with real ones. A delalloc - * mapping can be replaced by several real ones if the free space is - * fragmented. + * delalloc reservations are converted into unwritten mappings by + * allocating blocks and replacing the delalloc mapping with real ones. + * A delalloc mapping can be replaced by several unwritten ones if the + * free space is fragmented. + * + * D: --RRRRRRSSSRRRRRRRR--- + * C: ------UUUUUUU--------- * * We want to adapt the delalloc mechanism for copy-on-write, since the * write paths are similar. The first two steps (creating the reservation @@ -101,13 +112,29 @@ * Block-aligned directio writes will use the same mechanism as buffered * writes. * + * Just prior to submitting the actual disk write requests, we convert + * the extents representing the range of the file actually being written + * (as opposed to extra pieces created for the cowextsize hint) to real + * extents. This will become important in the next step: + * + * D: --RRRRRRSSSRRRRRRRR--- + * C: ------UUrrUUU--------- + * * CoW remapping must be done after the data block write completes, * because we don't want to destroy the old data fork map until we're sure * the new block has been written. Since the new mappings are kept in a * separate fork, we can simply iterate these mappings to find the ones * that cover the file blocks that we just CoW'd. For each extent, simply * unmap the corresponding range in the data fork, map the new range into - * the data fork, and remove the extent from the CoW fork. + * the data fork, and remove the extent from the CoW fork. Because of + * the presence of the cowextsize hint, however, we must be careful + * only to remap the blocks that we've actually written out -- we must + * never remap delalloc reservations nor CoW staging blocks that have + * yet to be written. This corresponds exactly to the real extents in + * the CoW fork: + * + * D: --RRRRRRrrSRRRRRRRR--- + * C: ------UU--UUU--------- * * Since the remapping operation can be applied to an arbitrary file * range, we record the need for the remap step as a flag in the ioend @@ -243,12 +270,11 @@ xfs_reflink_reserve_cow( struct xfs_bmbt_irec *imap, bool *shared) { - struct xfs_bmbt_irec got, prev; - xfs_fileoff_t end_fsb, orig_end_fsb; - int eof = 0, error = 0; - bool trimmed; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); + struct xfs_bmbt_irec got; + int error = 0; + bool eof = false, trimmed; xfs_extnum_t idx; - xfs_extlen_t align; /* * Search the COW fork extent list first. This serves two purposes: @@ -258,8 +284,9 @@ xfs_reflink_reserve_cow( * extent list is generally faster than going out to the shared extent * tree. */ - xfs_bmap_search_extents(ip, imap->br_startoff, XFS_COW_FORK, &eof, &idx, - &got, &prev); + + if (!xfs_iext_lookup_extent(ip, ifp, imap->br_startoff, &idx, &got)) + eof = true; if (!eof && got.br_startoff <= imap->br_startoff) { trace_xfs_reflink_cow_found(ip, imap); xfs_trim_extent(imap, got.br_startoff, got.br_blockcount); @@ -285,245 +312,265 @@ xfs_reflink_reserve_cow( if (error) return error; - end_fsb = orig_end_fsb = imap->br_startoff + imap->br_blockcount; - - align = xfs_eof_alignment(ip, xfs_get_cowextsz_hint(ip)); - if (align) - end_fsb = roundup_64(end_fsb, align); - -retry: error = xfs_bmapi_reserve_delalloc(ip, XFS_COW_FORK, imap->br_startoff, - end_fsb - imap->br_startoff, &got, &prev, &idx, eof); - switch (error) { - case 0: - break; - case -ENOSPC: - case -EDQUOT: - /* retry without any preallocation */ + imap->br_blockcount, 0, &got, &idx, eof); + if (error == -ENOSPC || error == -EDQUOT) trace_xfs_reflink_cow_enospc(ip, imap); - if (end_fsb != orig_end_fsb) { - end_fsb = orig_end_fsb; - goto retry; - } - /*FALLTHRU*/ - default: + if (error) return error; - } - - if (end_fsb != orig_end_fsb) - xfs_inode_set_cowblocks_tag(ip); trace_xfs_reflink_cow_alloc(ip, &got); return 0; } -/* Allocate all CoW reservations covering a range of blocks in a file. */ -static int -__xfs_reflink_allocate_cow( - struct xfs_inode *ip, - xfs_fileoff_t *offset_fsb, - xfs_fileoff_t end_fsb) +/* Convert part of an unwritten CoW extent to a real one. */ +STATIC int +xfs_reflink_convert_cow_extent( + struct xfs_inode *ip, + struct xfs_bmbt_irec *imap, + xfs_fileoff_t offset_fsb, + xfs_filblks_t count_fsb, + struct xfs_defer_ops *dfops) { - struct xfs_mount *mp = ip->i_mount; - struct xfs_bmbt_irec imap; - struct xfs_defer_ops dfops; - struct xfs_trans *tp; - xfs_fsblock_t first_block; - int nimaps = 1, error; - bool shared; - - xfs_defer_init(&dfops, &first_block); + xfs_fsblock_t first_block; + int nimaps = 1; - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, - XFS_TRANS_RESERVE, &tp); - if (error) - return error; + if (imap->br_state == XFS_EXT_NORM) + return 0; - xfs_ilock(ip, XFS_ILOCK_EXCL); + xfs_trim_extent(imap, offset_fsb, count_fsb); + trace_xfs_reflink_convert_cow(ip, imap); + if (imap->br_blockcount == 0) + return 0; + return xfs_bmapi_write(NULL, ip, imap->br_startoff, imap->br_blockcount, + XFS_BMAPI_COWFORK | XFS_BMAPI_CONVERT, &first_block, + 0, imap, &nimaps, dfops); +} - /* Read extent from the source file. */ - nimaps = 1; - error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb, - &imap, &nimaps, 0); - if (error) - goto out_unlock; - ASSERT(nimaps == 1); +/* Convert all of the unwritten CoW extents in a file's range to real ones. */ +int +xfs_reflink_convert_cow( + struct xfs_inode *ip, + xfs_off_t offset, + xfs_off_t count) +{ + struct xfs_bmbt_irec got; + struct xfs_defer_ops dfops; + struct xfs_mount *mp = ip->i_mount; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); + xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); + xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + count); + xfs_extnum_t idx; + bool found; + int error = 0; - error = xfs_reflink_reserve_cow(ip, &imap, &shared); - if (error) - goto out_trans_cancel; + xfs_ilock(ip, XFS_ILOCK_EXCL); - if (!shared) { - *offset_fsb = imap.br_startoff + imap.br_blockcount; - goto out_trans_cancel; + /* Convert all the extents to real from unwritten. */ + for (found = xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got); + found && got.br_startoff < end_fsb; + found = xfs_iext_get_extent(ifp, ++idx, &got)) { + error = xfs_reflink_convert_cow_extent(ip, &got, offset_fsb, + end_fsb - offset_fsb, &dfops); + if (error) + break; } - xfs_trans_ijoin(tp, ip, 0); - error = xfs_bmapi_write(tp, ip, imap.br_startoff, imap.br_blockcount, - XFS_BMAPI_COWFORK, &first_block, - XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK), - &imap, &nimaps, &dfops); - if (error) - goto out_trans_cancel; - - error = xfs_defer_finish(&tp, &dfops, NULL); - if (error) - goto out_trans_cancel; - - error = xfs_trans_commit(tp); - - *offset_fsb = imap.br_startoff + imap.br_blockcount; -out_unlock: + /* Finish up. */ xfs_iunlock(ip, XFS_ILOCK_EXCL); return error; -out_trans_cancel: - xfs_defer_cancel(&dfops); - xfs_trans_cancel(tp); - goto out_unlock; } -/* Allocate all CoW reservations covering a part of a file. */ +/* Allocate all CoW reservations covering a range of blocks in a file. */ int -xfs_reflink_allocate_cow_range( +xfs_reflink_allocate_cow( struct xfs_inode *ip, - xfs_off_t offset, - xfs_off_t count) + struct xfs_bmbt_irec *imap, + bool *shared, + uint *lockmode) { struct xfs_mount *mp = ip->i_mount; - xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); - xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + count); - int error; + xfs_fileoff_t offset_fsb = imap->br_startoff; + xfs_filblks_t count_fsb = imap->br_blockcount; + struct xfs_bmbt_irec got; + struct xfs_defer_ops dfops; + struct xfs_trans *tp = NULL; + xfs_fsblock_t first_block; + int nimaps, error = 0; + bool trimmed; + xfs_filblks_t resaligned; + xfs_extlen_t resblks = 0; + xfs_extnum_t idx; +retry: ASSERT(xfs_is_reflink_inode(ip)); - - trace_xfs_reflink_allocate_cow_range(ip, offset, count); + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)); /* - * Make sure that the dquots are there. + * Even if the extent is not shared we might have a preallocation for + * it in the COW fork. If so use it. */ - error = xfs_qm_dqattach(ip, 0); - if (error) - return error; + if (xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &idx, &got) && + got.br_startoff <= offset_fsb) { + *shared = true; - while (offset_fsb < end_fsb) { - error = __xfs_reflink_allocate_cow(ip, &offset_fsb, end_fsb); - if (error) { - trace_xfs_reflink_allocate_cow_range_error(ip, error, - _RET_IP_); - break; + /* If we have a real allocation in the COW fork we're done. */ + if (!isnullstartblock(got.br_startblock)) { + xfs_trim_extent(&got, offset_fsb, count_fsb); + *imap = got; + goto convert; } + + xfs_trim_extent(imap, got.br_startoff, got.br_blockcount); + } else { + error = xfs_reflink_trim_around_shared(ip, imap, shared, &trimmed); + if (error || !*shared) + goto out; } + if (!tp) { + resaligned = xfs_aligned_fsb_count(imap->br_startoff, + imap->br_blockcount, xfs_get_cowextsz_hint(ip)); + resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); + + xfs_iunlock(ip, *lockmode); + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); + *lockmode = XFS_ILOCK_EXCL; + xfs_ilock(ip, *lockmode); + + if (error) + return error; + + error = xfs_qm_dqattach_locked(ip, 0); + if (error) + goto out; + goto retry; + } + + error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, + XFS_QMOPT_RES_REGBLKS); + if (error) + goto out; + + xfs_trans_ijoin(tp, ip, 0); + + xfs_defer_init(&dfops, &first_block); + nimaps = 1; + + /* Allocate the entire reservation as unwritten blocks. */ + error = xfs_bmapi_write(tp, ip, imap->br_startoff, imap->br_blockcount, + XFS_BMAPI_COWFORK | XFS_BMAPI_PREALLOC, &first_block, + resblks, imap, &nimaps, &dfops); + if (error) + goto out_bmap_cancel; + + /* Finish up. */ + error = xfs_defer_finish(&tp, &dfops, NULL); + if (error) + goto out_bmap_cancel; + + error = xfs_trans_commit(tp); + if (error) + return error; +convert: + return xfs_reflink_convert_cow_extent(ip, imap, offset_fsb, count_fsb, + &dfops); +out_bmap_cancel: + xfs_defer_cancel(&dfops); + xfs_trans_unreserve_quota_nblks(tp, ip, (long)resblks, 0, + XFS_QMOPT_RES_REGBLKS); +out: + if (tp) + xfs_trans_cancel(tp); return error; } /* - * Find the CoW reservation (and whether or not it needs block allocation) - * for a given byte offset of a file. + * Find the CoW reservation for a given byte offset of a file. */ bool xfs_reflink_find_cow_mapping( struct xfs_inode *ip, xfs_off_t offset, - struct xfs_bmbt_irec *imap, - bool *need_alloc) + struct xfs_bmbt_irec *imap) { - struct xfs_bmbt_irec irec; - struct xfs_ifork *ifp; - struct xfs_bmbt_rec_host *gotp; - xfs_fileoff_t bno; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); + xfs_fileoff_t offset_fsb; + struct xfs_bmbt_irec got; xfs_extnum_t idx; ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)); ASSERT(xfs_is_reflink_inode(ip)); - /* Find the extent in the CoW fork. */ - ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - bno = XFS_B_TO_FSBT(ip->i_mount, offset); - gotp = xfs_iext_bno_to_ext(ifp, bno, &idx); - if (!gotp) + offset_fsb = XFS_B_TO_FSBT(ip->i_mount, offset); + if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got)) return false; - - xfs_bmbt_get_all(gotp, &irec); - if (bno >= irec.br_startoff + irec.br_blockcount || - bno < irec.br_startoff) + if (got.br_startoff > offset_fsb) return false; trace_xfs_reflink_find_cow_mapping(ip, offset, 1, XFS_IO_OVERWRITE, - &irec); - - /* If it's still delalloc, we must allocate later. */ - *imap = irec; - *need_alloc = !!(isnullstartblock(irec.br_startblock)); - + &got); + *imap = got; return true; } /* * Trim an extent to end at the next CoW reservation past offset_fsb. */ -int +void xfs_reflink_trim_irec_to_next_cow( struct xfs_inode *ip, xfs_fileoff_t offset_fsb, struct xfs_bmbt_irec *imap) { - struct xfs_bmbt_irec irec; - struct xfs_ifork *ifp; - struct xfs_bmbt_rec_host *gotp; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); + struct xfs_bmbt_irec got; xfs_extnum_t idx; if (!xfs_is_reflink_inode(ip)) - return 0; + return; /* Find the extent in the CoW fork. */ - ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - gotp = xfs_iext_bno_to_ext(ifp, offset_fsb, &idx); - if (!gotp) - return 0; - xfs_bmbt_get_all(gotp, &irec); + if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got)) + return; /* This is the extent before; try sliding up one. */ - if (irec.br_startoff < offset_fsb) { - idx++; - if (idx >= ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) - return 0; - gotp = xfs_iext_get_ext(ifp, idx); - xfs_bmbt_get_all(gotp, &irec); + if (got.br_startoff < offset_fsb) { + if (!xfs_iext_get_extent(ifp, idx + 1, &got)) + return; } - if (irec.br_startoff >= imap->br_startoff + imap->br_blockcount) - return 0; + if (got.br_startoff >= imap->br_startoff + imap->br_blockcount) + return; - imap->br_blockcount = irec.br_startoff - imap->br_startoff; + imap->br_blockcount = got.br_startoff - imap->br_startoff; trace_xfs_reflink_trim_irec(ip, imap); - - return 0; } /* - * Cancel all pending CoW reservations for some block range of an inode. + * Cancel CoW reservations for some block range of an inode. + * + * If cancel_real is true this function cancels all COW fork extents for the + * inode; if cancel_real is false, real extents are not cleared. */ int xfs_reflink_cancel_cow_blocks( struct xfs_inode *ip, struct xfs_trans **tpp, xfs_fileoff_t offset_fsb, - xfs_fileoff_t end_fsb) + xfs_fileoff_t end_fsb, + bool cancel_real) { struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - struct xfs_bmbt_irec got, prev, del; + struct xfs_bmbt_irec got, del; xfs_extnum_t idx; xfs_fsblock_t firstfsb; struct xfs_defer_ops dfops; - int error = 0, eof = 0; + int error = 0; if (!xfs_is_reflink_inode(ip)) return 0; - - xfs_bmap_search_extents(ip, offset_fsb, XFS_COW_FORK, &eof, &idx, - &got, &prev); - if (eof) + if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got)) return 0; while (got.br_startoff < end_fsb) { @@ -536,7 +583,7 @@ xfs_reflink_cancel_cow_blocks( &idx, &got, &del); if (error) break; - } else { + } else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) { xfs_trans_ijoin(*tpp, ip, 0); xfs_defer_init(&dfops, &firstfsb); @@ -566,9 +613,8 @@ xfs_reflink_cancel_cow_blocks( xfs_bmap_del_extent_cow(ip, &idx, &got, &del); } - if (++idx >= ifp->if_bytes / sizeof(struct xfs_bmbt_rec)) + if (!xfs_iext_get_extent(ifp, ++idx, &got)) break; - xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &got); } /* clear tag if cow fork is emptied */ @@ -579,13 +625,17 @@ xfs_reflink_cancel_cow_blocks( } /* - * Cancel all pending CoW reservations for some byte range of an inode. + * Cancel CoW reservations for some byte range of an inode. + * + * If cancel_real is true this function cancels all COW fork extents for the + * inode; if cancel_real is false, real extents are not cleared. */ int xfs_reflink_cancel_cow_range( struct xfs_inode *ip, xfs_off_t offset, - xfs_off_t count) + xfs_off_t count, + bool cancel_real) { struct xfs_trans *tp; xfs_fileoff_t offset_fsb; @@ -611,7 +661,8 @@ xfs_reflink_cancel_cow_range( xfs_trans_ijoin(tp, ip, 0); /* Scrape out the old CoW reservations */ - error = xfs_reflink_cancel_cow_blocks(ip, &tp, offset_fsb, end_fsb); + error = xfs_reflink_cancel_cow_blocks(ip, &tp, offset_fsb, end_fsb, + cancel_real); if (error) goto out_cancel; @@ -638,13 +689,13 @@ xfs_reflink_end_cow( xfs_off_t count) { struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - struct xfs_bmbt_irec got, prev, del; + struct xfs_bmbt_irec got, del; struct xfs_trans *tp; xfs_fileoff_t offset_fsb; xfs_fileoff_t end_fsb; xfs_fsblock_t firstfsb; struct xfs_defer_ops dfops; - int error, eof = 0; + int error; unsigned int resblks; xfs_filblks_t rlen; xfs_extnum_t idx; @@ -668,13 +719,11 @@ xfs_reflink_end_cow( xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); - xfs_bmap_search_extents(ip, end_fsb - 1, XFS_COW_FORK, &eof, &idx, - &got, &prev); - /* If there is a hole at end_fsb - 1 go to the previous extent */ - if (eof || got.br_startoff > end_fsb) { + if (!xfs_iext_lookup_extent(ip, ifp, end_fsb - 1, &idx, &got) || + got.br_startoff > end_fsb) { ASSERT(idx > 0); - xfs_bmbt_get_all(xfs_iext_get_ext(ifp, --idx), &got); + xfs_iext_get_extent(ifp, --idx, &got); } /* Walk backwards until we're out of the I/O range... */ @@ -690,6 +739,16 @@ xfs_reflink_end_cow( ASSERT(!isnullstartblock(got.br_startblock)); + /* + * Don't remap unwritten extents; these are + * speculatively preallocated CoW extents that have been + * allocated but have not yet been involved in a write. + */ + if (got.br_state == XFS_EXT_UNWRITTEN) { + idx--; + goto next_extent; + } + /* Unmap the old blocks in the data fork. */ xfs_defer_init(&dfops, &firstfsb); rlen = del.br_blockcount; @@ -722,11 +781,9 @@ xfs_reflink_end_cow( error = xfs_defer_finish(&tp, &dfops, ip); if (error) goto out_defer; - next_extent: - if (idx < 0) + if (!xfs_iext_get_extent(ifp, idx, &got)) break; - xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &got); } error = xfs_trans_commit(tp); @@ -906,13 +963,14 @@ STATIC int xfs_reflink_update_dest( struct xfs_inode *dest, xfs_off_t newlen, - xfs_extlen_t cowextsize) + xfs_extlen_t cowextsize, + bool is_dedupe) { struct xfs_mount *mp = dest->i_mount; struct xfs_trans *tp; int error; - if (newlen <= i_size_read(VFS_I(dest)) && cowextsize == 0) + if (is_dedupe && newlen <= i_size_read(VFS_I(dest)) && cowextsize == 0) return 0; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp); @@ -933,6 +991,10 @@ xfs_reflink_update_dest( dest->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE; } + if (!is_dedupe) { + xfs_trans_ichgtime(tp, dest, + XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + } xfs_trans_log_inode(tp, dest, XFS_ILOG_CORE); error = xfs_trans_commit(tp); @@ -1165,111 +1227,6 @@ err: } /* - * Read a page's worth of file data into the page cache. Return the page - * locked. - */ -static struct page * -xfs_get_page( - struct inode *inode, - xfs_off_t offset) -{ - struct address_space *mapping; - struct page *page; - pgoff_t n; - - n = offset >> PAGE_SHIFT; - mapping = inode->i_mapping; - page = read_mapping_page(mapping, n, NULL); - if (IS_ERR(page)) - return page; - if (!PageUptodate(page)) { - put_page(page); - return ERR_PTR(-EIO); - } - lock_page(page); - return page; -} - -/* - * Compare extents of two files to see if they are the same. - */ -static int -xfs_compare_extents( - struct inode *src, - xfs_off_t srcoff, - struct inode *dest, - xfs_off_t destoff, - xfs_off_t len, - bool *is_same) -{ - xfs_off_t src_poff; - xfs_off_t dest_poff; - void *src_addr; - void *dest_addr; - struct page *src_page; - struct page *dest_page; - xfs_off_t cmp_len; - bool same; - int error; - - error = -EINVAL; - same = true; - while (len) { - src_poff = srcoff & (PAGE_SIZE - 1); - dest_poff = destoff & (PAGE_SIZE - 1); - cmp_len = min(PAGE_SIZE - src_poff, - PAGE_SIZE - dest_poff); - cmp_len = min(cmp_len, len); - ASSERT(cmp_len > 0); - - trace_xfs_reflink_compare_extents(XFS_I(src), srcoff, cmp_len, - XFS_I(dest), destoff); - - src_page = xfs_get_page(src, srcoff); - if (IS_ERR(src_page)) { - error = PTR_ERR(src_page); - goto out_error; - } - dest_page = xfs_get_page(dest, destoff); - if (IS_ERR(dest_page)) { - error = PTR_ERR(dest_page); - unlock_page(src_page); - put_page(src_page); - goto out_error; - } - src_addr = kmap_atomic(src_page); - dest_addr = kmap_atomic(dest_page); - - flush_dcache_page(src_page); - flush_dcache_page(dest_page); - - if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) - same = false; - - kunmap_atomic(dest_addr); - kunmap_atomic(src_addr); - unlock_page(dest_page); - unlock_page(src_page); - put_page(dest_page); - put_page(src_page); - - if (!same) - break; - - srcoff += cmp_len; - destoff += cmp_len; - len -= cmp_len; - } - - *is_same = same; - return 0; - -out_error: - trace_xfs_reflink_compare_extents_error(XFS_I(dest), error, _RET_IP_); - return error; -} - -/* * Link a range of blocks from one file to another. */ int @@ -1286,14 +1243,11 @@ xfs_reflink_remap_range( struct inode *inode_out = file_inode(file_out); struct xfs_inode *dest = XFS_I(inode_out); struct xfs_mount *mp = src->i_mount; - loff_t bs = inode_out->i_sb->s_blocksize; bool same_inode = (inode_in == inode_out); xfs_fileoff_t sfsbno, dfsbno; xfs_filblks_t fsblen; xfs_extlen_t cowextsize; - loff_t isize; ssize_t ret; - loff_t blen; if (!xfs_sb_version_hasreflink(&mp->m_sb)) return -EOPNOTSUPP; @@ -1302,34 +1256,14 @@ xfs_reflink_remap_range( return -EIO; /* Lock both files against IO */ - if (same_inode) { - xfs_ilock(src, XFS_IOLOCK_EXCL); + lock_two_nondirectories(inode_in, inode_out); + if (same_inode) xfs_ilock(src, XFS_MMAPLOCK_EXCL); - } else { - xfs_lock_two_inodes(src, dest, XFS_IOLOCK_EXCL); + else xfs_lock_two_inodes(src, dest, XFS_MMAPLOCK_EXCL); - } - - /* Don't touch certain kinds of inodes */ - ret = -EPERM; - if (IS_IMMUTABLE(inode_out)) - goto out_unlock; - ret = -ETXTBSY; - if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out)) - goto out_unlock; - - - /* Don't reflink dirs, pipes, sockets... */ - ret = -EISDIR; - if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) - goto out_unlock; + /* Check file eligibility and prepare for block sharing. */ ret = -EINVAL; - if (S_ISFIFO(inode_in->i_mode) || S_ISFIFO(inode_out->i_mode)) - goto out_unlock; - if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) - goto out_unlock; - /* Don't reflink realtime inodes */ if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) goto out_unlock; @@ -1338,91 +1272,18 @@ xfs_reflink_remap_range( if (IS_DAX(inode_in) || IS_DAX(inode_out)) goto out_unlock; - /* Are we going all the way to the end? */ - isize = i_size_read(inode_in); - if (isize == 0) { - ret = 0; - goto out_unlock; - } - - if (len == 0) - len = isize - pos_in; - - /* Ensure offsets don't wrap and the input is inside i_size */ - if (pos_in + len < pos_in || pos_out + len < pos_out || - pos_in + len > isize) - goto out_unlock; - - /* Don't allow dedupe past EOF in the dest file */ - if (is_dedupe) { - loff_t disize; - - disize = i_size_read(inode_out); - if (pos_out >= disize || pos_out + len > disize) - goto out_unlock; - } - - /* If we're linking to EOF, continue to the block boundary. */ - if (pos_in + len == isize) - blen = ALIGN(isize, bs) - pos_in; - else - blen = len; - - /* Only reflink if we're aligned to block boundaries */ - if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) || - !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs)) - goto out_unlock; - - /* Don't allow overlapped reflink within the same file */ - if (same_inode) { - if (pos_out + blen > pos_in && pos_out < pos_in + blen) - goto out_unlock; - } - - /* Wait for the completion of any pending IOs on both files */ - inode_dio_wait(inode_in); - if (!same_inode) - inode_dio_wait(inode_out); - - ret = filemap_write_and_wait_range(inode_in->i_mapping, - pos_in, pos_in + len - 1); - if (ret) - goto out_unlock; - - ret = filemap_write_and_wait_range(inode_out->i_mapping, - pos_out, pos_out + len - 1); - if (ret) + ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out, + &len, is_dedupe); + if (ret <= 0) goto out_unlock; trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out); - /* - * Check that the extents are the same. - */ - if (is_dedupe) { - bool is_same = false; - - ret = xfs_compare_extents(inode_in, pos_in, inode_out, pos_out, - len, &is_same); - if (ret) - goto out_unlock; - if (!is_same) { - ret = -EBADE; - goto out_unlock; - } - } - + /* Set flags and remap blocks. */ ret = xfs_reflink_set_inode_flag(src, dest); if (ret) goto out_unlock; - /* - * Invalidate the page cache so that we can clear any CoW mappings - * in the destination file. - */ - truncate_inode_pages_range(&inode_out->i_data, pos_out, - PAGE_ALIGN(pos_out + len) - 1); - dfsbno = XFS_B_TO_FSBT(mp, pos_out); sfsbno = XFS_B_TO_FSBT(mp, pos_in); fsblen = XFS_B_TO_FSB(mp, len); @@ -1431,6 +1292,10 @@ xfs_reflink_remap_range( if (ret) goto out_unlock; + /* Zap any page cache for the destination file's range. */ + truncate_inode_pages_range(&inode_out->i_data, pos_out, + PAGE_ALIGN(pos_out + len) - 1); + /* * Carry the cowextsize hint from src to dest if we're sharing the * entire source file to the entire destination file, the source file @@ -1443,15 +1308,14 @@ xfs_reflink_remap_range( !(dest->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)) cowextsize = src->i_d.di_cowextsize; - ret = xfs_reflink_update_dest(dest, pos_out + len, cowextsize); + ret = xfs_reflink_update_dest(dest, pos_out + len, cowextsize, + is_dedupe); out_unlock: xfs_iunlock(src, XFS_MMAPLOCK_EXCL); - xfs_iunlock(src, XFS_IOLOCK_EXCL); - if (src->i_ino != dest->i_ino) { + if (!same_inode) xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); - xfs_iunlock(dest, XFS_IOLOCK_EXCL); - } + unlock_two_nondirectories(inode_in, inode_out); if (ret) trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); return ret; @@ -1595,7 +1459,7 @@ next: * We didn't find any shared blocks so turn off the reflink flag. * First, get rid of any leftover CoW mappings. */ - error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF); + error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF, true); if (error) return error; @@ -1697,37 +1561,3 @@ out: trace_xfs_reflink_unshare_error(ip, error, _RET_IP_); return error; } - -/* - * Does this inode have any real CoW reservations? - */ -bool -xfs_reflink_has_real_cow_blocks( - struct xfs_inode *ip) -{ - struct xfs_bmbt_irec irec; - struct xfs_ifork *ifp; - struct xfs_bmbt_rec_host *gotp; - xfs_extnum_t idx; - - if (!xfs_is_reflink_inode(ip)) - return false; - - /* Go find the old extent in the CoW fork. */ - ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - gotp = xfs_iext_bno_to_ext(ifp, 0, &idx); - while (gotp) { - xfs_bmbt_get_all(gotp, &irec); - - if (!isnullstartblock(irec.br_startblock)) - return true; - - /* Roll on... */ - idx++; - if (idx >= ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) - break; - gotp = xfs_iext_get_ext(ifp, idx); - } - - return false; -} |