diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-13 20:28:22 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-13 20:28:22 -0700 |
commit | 35a891be96f1f8e1227e6ad3ca827b8a08ce47ea (patch) | |
tree | ab67c3b97a49f8e8ba2d011d4a706d52bcde318b | |
parent | 40bd3a5f341b4ef4c6a49fb68938247d3065d8ad (diff) | |
parent | feac470e3642e8956ac9b7f14224e6b301b9219d (diff) |
Merge tag 'xfs-reflink-for-linus-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
< XFS has gained super CoW powers! >
----------------------------------
\ ^__^
\ (oo)\_______
(__)\ )\/\
||----w |
|| ||
Pull XFS support for shared data extents from Dave Chinner:
"This is the second part of the XFS updates for this merge cycle. This
pullreq contains the new shared data extents feature for XFS.
Given the complexity and size of this change I am expecting - like the
addition of reverse mapping last cycle - that there will be some
follow-up bug fixes and cleanups around the -rc3 stage for issues that
I'm sure will show up once the code hits a wider userbase.
What it is:
At the most basic level we are simply adding shared data extents to
XFS - i.e. a single extent on disk can now have multiple owners. To do
this we have to add new on-disk features to both track the shared
extents and the number of times they've been shared. This is done by
the new "refcount" btree that sits in every allocation group. When we
share or unshare an extent, this tree gets updated.
Along with this new tree, the reverse mapping tree needs to be updated
to track each owner or a shared extent. This also needs to be updated
ever share/unshare operation. These interactions at extent allocation
and freeing time have complex ordering and recovery constraints, so
there's a significant amount of new intent-based transaction code to
ensure that operations are performed atomically from both the runtime
and integrity/crash recovery perspectives.
We also need to break sharing when writes hit a shared extent - this
is where the new copy-on-write implementation comes in. We allocate
new storage and copy the original data along with the overwrite data
into the new location. We only do this for data as we don't share
metadata at all - each inode has it's own metadata that tracks the
shared data extents, the extents undergoing CoW and it's own private
extents.
Of course, being XFS, nothing is simple - we use delayed allocation
for CoW similar to how we use it for normal writes. ENOSPC is a
significant issue here - we build on the reservation code added in
4.8-rc1 with the reverse mapping feature to ensure we don't get
spurious ENOSPC issues part way through a CoW operation. These
mechanisms also help minimise fragmentation due to repeated CoW
operations. To further reduce fragmentation overhead, we've also
introduced a CoW extent size hint, which indicates how large a region
we should allocate when we execute a CoW operation.
With all this functionality in place, we can hook up .copy_file_range,
.clone_file_range and .dedupe_file_range and we gain all the
capabilities of reflink and other vfs provided functionality that
enable manipulation to shared extents. We also added a fallocate mode
that explicitly unshares a range of a file, which we implemented as an
explicit CoW of all the shared extents in a file.
As such, it's a huge chunk of new functionality with new on-disk
format features and internal infrastructure. It warns at mount time as
an experimental feature and that it may eat data (as we do with all
new on-disk features until they stabilise). We have not released
userspace suport for it yet - userspace support currently requires
download from Darrick's xfsprogs repo and build from source, so the
access to this feature is really developer/tester only at this point.
Initial userspace support will be released at the same time the kernel
with this code in it is released.
The new code causes 5-6 new failures with xfstests - these aren't
serious functional failures but things the output of tests changing
slightly due to perturbations in layouts, space usage, etc. OTOH,
we've added 150+ new tests to xfstests that specifically exercise this
new functionality so it's got far better test coverage than any
functionality we've previously added to XFS.
Darrick has done a pretty amazing job getting us to this stage, and
special mention also needs to go to Christoph (review, testing,
improvements and bug fixes) and Brian (caught several intricate bugs
during review) for the effort they've also put in.
Summary:
- unshare range (FALLOC_FL_UNSHARE) support for fallocate
- copy-on-write extent size hints (FS_XFLAG_COWEXTSIZE) for fsxattr
interface
- shared extent support for XFS
- copy-on-write support for shared extents
- copy_file_range support
- clone_file_range support (implements reflink)
- dedupe_file_range support
- defrag support for reverse mapping enabled filesystems"
* tag 'xfs-reflink-for-linus-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (71 commits)
xfs: convert COW blocks to real blocks before unwritten extent conversion
xfs: rework refcount cow recovery error handling
xfs: clear reflink flag if setting realtime flag
xfs: fix error initialization
xfs: fix label inaccuracies
xfs: remove isize check from unshare operation
xfs: reduce stack usage of _reflink_clear_inode_flag
xfs: check inode reflink flag before calling reflink functions
xfs: implement swapext for rmap filesystems
xfs: refactor swapext code
xfs: various swapext cleanups
xfs: recognize the reflink feature bit
xfs: simulate per-AG reservations being critically low
xfs: don't mix reflink and DAX mode for now
xfs: check for invalid inode reflink flags
xfs: set a default CoW extent size of 32 blocks
xfs: convert unwritten status of reverse mappings for shared files
xfs: use interval query for rmap alloc operations on shared files
xfs: add shared rmap map/unmap/convert log item types
xfs: increase log reservations for reflink
...
76 files changed, 10580 insertions, 310 deletions
diff --git a/fs/open.c b/fs/open.c index a7719cfb7257..d3ed8171e8e0 100644 --- a/fs/open.c +++ b/fs/open.c @@ -267,6 +267,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) (mode & ~FALLOC_FL_INSERT_RANGE)) return -EINVAL; + /* Unshare range should only be used with allocate mode. */ + if ((mode & FALLOC_FL_UNSHARE_RANGE) && + (mode & ~(FALLOC_FL_UNSHARE_RANGE | FALLOC_FL_KEEP_SIZE))) + return -EINVAL; + if (!(file->f_mode & FMODE_WRITE)) return -EBADF; diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index 584e87e11cb6..26ef1958b65b 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -55,6 +55,8 @@ xfs-y += $(addprefix libxfs/, \ xfs_ag_resv.o \ xfs_rmap.o \ xfs_rmap_btree.o \ + xfs_refcount.o \ + xfs_refcount_btree.o \ xfs_sb.o \ xfs_symlink_remote.o \ xfs_trans_resv.o \ @@ -88,6 +90,7 @@ xfs-y += xfs_aops.o \ xfs_message.o \ xfs_mount.o \ xfs_mru_cache.o \ + xfs_reflink.o \ xfs_stats.o \ xfs_super.o \ xfs_symlink.o \ @@ -100,16 +103,20 @@ xfs-y += xfs_aops.o \ # low-level transaction/log code xfs-y += xfs_log.o \ xfs_log_cil.o \ + xfs_bmap_item.o \ xfs_buf_item.o \ xfs_extfree_item.o \ xfs_icreate_item.o \ xfs_inode_item.o \ + xfs_refcount_item.o \ xfs_rmap_item.o \ xfs_log_recover.o \ xfs_trans_ail.o \ + xfs_trans_bmap.o \ xfs_trans_buf.o \ xfs_trans_extfree.o \ xfs_trans_inode.o \ + xfs_trans_refcount.o \ xfs_trans_rmap.o \ # optional features diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c index e3ae0f2b4294..e5ebc3770460 100644 --- a/fs/xfs/libxfs/xfs_ag_resv.c +++ b/fs/xfs/libxfs/xfs_ag_resv.c @@ -38,6 +38,7 @@ #include "xfs_trans_space.h" #include "xfs_rmap_btree.h" #include "xfs_btree.h" +#include "xfs_refcount_btree.h" /* * Per-AG Block Reservations @@ -108,7 +109,9 @@ xfs_ag_resv_critical( trace_xfs_ag_resv_critical(pag, type, avail); /* Critically low if less than 10% or max btree height remains. */ - return avail < orig / 10 || avail < XFS_BTREE_MAXLEVELS; + return XFS_TEST_ERROR(avail < orig / 10 || avail < XFS_BTREE_MAXLEVELS, + pag->pag_mount, XFS_ERRTAG_AG_RESV_CRITICAL, + XFS_RANDOM_AG_RESV_CRITICAL); } /* @@ -228,6 +231,11 @@ xfs_ag_resv_init( if (pag->pag_meta_resv.ar_asked == 0) { ask = used = 0; + error = xfs_refcountbt_calc_reserves(pag->pag_mount, + pag->pag_agno, &ask, &used); + if (error) + goto out; + error = __xfs_ag_resv_init(pag, XFS_AG_RESV_METADATA, ask, used); if (error) @@ -238,6 +246,11 @@ xfs_ag_resv_init( if (pag->pag_agfl_resv.ar_asked == 0) { ask = used = 0; + error = xfs_rmapbt_calc_reserves(pag->pag_mount, pag->pag_agno, + &ask, &used); + if (error) + goto out; + error = __xfs_ag_resv_init(pag, XFS_AG_RESV_AGFL, ask, used); if (error) goto out; diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index ca75dc90ebe0..effb64cf714f 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -52,10 +52,23 @@ STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *); STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *, xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *); +unsigned int +xfs_refc_block( + struct xfs_mount *mp) +{ + if (xfs_sb_version_hasrmapbt(&mp->m_sb)) + return XFS_RMAP_BLOCK(mp) + 1; + if (xfs_sb_version_hasfinobt(&mp->m_sb)) + return XFS_FIBT_BLOCK(mp) + 1; + return XFS_IBT_BLOCK(mp) + 1; +} + xfs_extlen_t xfs_prealloc_blocks( struct xfs_mount *mp) { + if (xfs_sb_version_hasreflink(&mp->m_sb)) + return xfs_refc_block(mp) + 1; if (xfs_sb_version_hasrmapbt(&mp->m_sb)) return XFS_RMAP_BLOCK(mp) + 1; if (xfs_sb_version_hasfinobt(&mp->m_sb)) @@ -115,6 +128,8 @@ xfs_alloc_ag_max_usable( blocks++; /* finobt root block */ if (xfs_sb_version_hasrmapbt(&mp->m_sb)) blocks++; /* rmap root block */ + if (xfs_sb_version_hasreflink(&mp->m_sb)) + blocks++; /* refcount root block */ return mp->m_sb.sb_agblocks - blocks; } @@ -2321,6 +2336,9 @@ xfs_alloc_log_agf( offsetof(xfs_agf_t, agf_btreeblks), offsetof(xfs_agf_t, agf_uuid), offsetof(xfs_agf_t, agf_rmap_blocks), + offsetof(xfs_agf_t, agf_refcount_blocks), + offsetof(xfs_agf_t, agf_refcount_root), + offsetof(xfs_agf_t, agf_refcount_level), /* needed so that we don't log the whole rest of the structure: */ offsetof(xfs_agf_t, agf_spare64), sizeof(xfs_agf_t) @@ -2458,6 +2476,10 @@ xfs_agf_verify( be32_to_cpu(agf->agf_btreeblks) > be32_to_cpu(agf->agf_length)) return false; + if (xfs_sb_version_hasreflink(&mp->m_sb) && + be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS) + return false; + return true;; } @@ -2578,6 +2600,7 @@ xfs_alloc_read_agf( be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]); pag->pagf_levels[XFS_BTNUM_RMAPi] = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]); + pag->pagf_refcount_level = be32_to_cpu(agf->agf_refcount_level); spin_lock_init(&pag->pagb_lock); pag->pagb_count = 0; pag->pagb_tree = RB_ROOT; diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 9d7f61d36645..c27344cf38e1 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -48,6 +48,7 @@ #include "xfs_filestream.h" #include "xfs_rmap.h" #include "xfs_ag_resv.h" +#include "xfs_refcount.h" kmem_zone_t *xfs_bmap_free_item_zone; @@ -140,7 +141,8 @@ xfs_bmbt_lookup_ge( */ static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork) { - return XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS && + return whichfork != XFS_COW_FORK && + XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS && XFS_IFORK_NEXTENTS(ip, whichfork) > XFS_IFORK_MAXEXT(ip, whichfork); } @@ -150,7 +152,8 @@ static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork) */ static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork) { - return XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE && + return whichfork != XFS_COW_FORK && + XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE && XFS_IFORK_NEXTENTS(ip, whichfork) <= XFS_IFORK_MAXEXT(ip, whichfork); } @@ -640,6 +643,7 @@ xfs_bmap_btree_to_extents( mp = ip->i_mount; ifp = XFS_IFORK_PTR(ip, whichfork); + ASSERT(whichfork != XFS_COW_FORK); ASSERT(ifp->if_flags & XFS_IFEXTENTS); ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE); rblock = ifp->if_broot; @@ -706,6 +710,7 @@ xfs_bmap_extents_to_btree( xfs_bmbt_ptr_t *pp; /* root block address pointer */ mp = ip->i_mount; + ASSERT(whichfork != XFS_COW_FORK); ifp = XFS_IFORK_PTR(ip, whichfork); ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS); @@ -748,6 +753,7 @@ xfs_bmap_extents_to_btree( args.type = XFS_ALLOCTYPE_START_BNO; args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino); } else if (dfops->dop_low) { +try_another_ag: args.type = XFS_ALLOCTYPE_START_BNO; args.fsbno = *firstblock; } else { @@ -762,6 +768,21 @@ xfs_bmap_extents_to_btree( xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; } + + /* + * During a CoW operation, the allocation and bmbt updates occur in + * different transactions. The mapping code tries to put new bmbt + * blocks near extents being mapped, but the only way to guarantee this + * is if the alloc and the mapping happen in a single transaction that + * has a block reservation. That isn't the case here, so if we run out + * of space we'll try again with another AG. + */ + if (xfs_sb_version_hasreflink(&cur->bc_mp->m_sb) && + args.fsbno == NULLFSBLOCK && + args.type == XFS_ALLOCTYPE_NEAR_BNO) { + dfops->dop_low = true; + goto try_another_ag; + } /* * Allocation can't fail, the space was reserved. */ @@ -837,6 +858,7 @@ xfs_bmap_local_to_extents_empty( { struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); + ASSERT(whichfork != XFS_COW_FORK); ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL); ASSERT(ifp->if_bytes == 0); ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) == 0); @@ -896,6 +918,7 @@ xfs_bmap_local_to_extents( * file currently fits in an inode. */ if (*firstblock == NULLFSBLOCK) { +try_another_ag: args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino); args.type = XFS_ALLOCTYPE_START_BNO; } else { @@ -908,6 +931,19 @@ xfs_bmap_local_to_extents( if (error) goto done; + /* + * During a CoW operation, the allocation and bmbt updates occur in + * different transactions. The mapping code tries to put new bmbt + * blocks near extents being mapped, but the only way to guarantee this + * is if the alloc and the mapping happen in a single transaction that + * has a block reservation. That isn't the case here, so if we run out + * of space we'll try again with another AG. + */ + if (xfs_sb_version_hasreflink(&ip->i_mount->m_sb) && + args.fsbno == NULLFSBLOCK && + args.type == XFS_ALLOCTYPE_NEAR_BNO) { + goto try_another_ag; + } /* Can't fail, the space was reserved. */ ASSERT(args.fsbno != NULLFSBLOCK); ASSERT(args.len == 1); @@ -1670,7 +1706,8 @@ xfs_bmap_one_block( */ STATIC int /* error */ xfs_bmap_add_extent_delay_real( - struct xfs_bmalloca *bma) + struct xfs_bmalloca *bma, + int whichfork) { struct xfs_bmbt_irec *new = &bma->got; int diff; /* temp value */ @@ -1688,11 +1725,14 @@ xfs_bmap_add_extent_delay_real( xfs_filblks_t temp=0; /* value for da_new calculations */ xfs_filblks_t temp2=0;/* value for da_new calculations */ int tmp_rval; /* partial logging flags */ - int whichfork = XFS_DATA_FORK; struct xfs_mount *mp; + xfs_extnum_t *nextents; mp = bma->ip->i_mount; ifp = XFS_IFORK_PTR(bma->ip, whichfork); + ASSERT(whichfork != XFS_ATTR_FORK); + nextents = (whichfork == XFS_COW_FORK ? &bma->ip->i_cnextents : + &bma->ip->i_d.di_nextents); ASSERT(bma->idx >= 0); ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec)); @@ -1706,6 +1746,9 @@ xfs_bmap_add_extent_delay_real( #define RIGHT r[1] #define PREV r[2] + if (whichfork == XFS_COW_FORK) + state |= BMAP_COWFORK; + /* * Set up a bunch of variables to make the tests simpler. */ @@ -1792,7 +1835,7 @@ xfs_bmap_add_extent_delay_real( trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_); xfs_iext_remove(bma->ip, bma->idx + 1, 2, state); - bma->ip->i_d.di_nextents--; + (*nextents)--; if (bma->cur == NULL) rval = XFS_ILOG_CORE | XFS_ILOG_DEXT; else { @@ -1894,7 +1937,7 @@ xfs_bmap_add_extent_delay_real( xfs_bmbt_set_startblock(ep, new->br_startblock); trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_); - bma->ip->i_d.di_nextents++; + (*nextents)++; if (bma->cur == NULL) rval = XFS_ILOG_CORE | XFS_ILOG_DEXT; else { @@ -1964,7 +2007,7 @@ xfs_bmap_add_extent_delay_real( temp = PREV.br_blockcount - new->br_blockcount; xfs_bmbt_set_blockcount(ep, temp); xfs_iext_insert(bma->ip, bma->idx, 1, new, state); - bma->ip->i_d.di_nextents++; + (*nextents)++; if (bma->cur == NULL) rval = XFS_ILOG_CORE | XFS_ILOG_DEXT; else { @@ -2048,7 +2091,7 @@ xfs_bmap_add_extent_delay_real( trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_); xfs_bmbt_set_blockcount(ep, temp); xfs_iext_insert(bma->ip, bma->idx + 1, 1, new, state); - bma->ip->i_d.di_nextents++; + (*nextents)++; if (bma->cur == NULL) rval = XFS_ILOG_CORE | XFS_ILOG_DEXT; else { @@ -2117,7 +2160,7 @@ xfs_bmap_add_extent_delay_real( RIGHT.br_blockcount = temp2; /* insert LEFT (r[0]) and RIGHT (r[1]) at the same time */ xfs_iext_insert(bma->ip, bma->idx + 1, 2, &LEFT, state); - bma->ip->i_d.di_nextents++; + (*nextents)++; if (bma->cur == NULL) rval = XFS_ILOG_CORE | XFS_ILOG_DEXT; else { @@ -2215,7 +2258,8 @@ xfs_bmap_add_extent_delay_real( xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork); done: - bma->logflags |= rval; + if (whichfork != XFS_COW_FORK) + bma->logflags |= rval; return error; #undef LEFT #undef RIGHT @@ -2759,6 +2803,7 @@ done: STATIC void xfs_bmap_add_extent_hole_delay( xfs_inode_t *ip, /* incore inode pointer */ + int whichfork, xfs_extnum_t *idx, /* extent number to update/insert */ xfs_bmbt_irec_t *new) /* new data to add to file extents */ { @@ -2770,8 +2815,10 @@ xfs_bmap_add_extent_hole_delay( int state; /* state bits, accessed thru macros */ xfs_filblks_t temp=0; /* temp for indirect calculations */ - ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK); + ifp = XFS_IFORK_PTR(ip, whichfork); state = 0; + if (whichfork == XFS_COW_FORK) + state |= BMAP_COWFORK; ASSERT(isnullstartblock(new->br_startblock)); /* @@ -2789,7 +2836,7 @@ xfs_bmap_add_extent_hole_delay( * Check and set flags if the current (right) segment exists. * If it doesn't exist, we're converting the hole at end-of-file. */ - if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) { + if (*idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) { state |= BMAP_RI |