linux/fs/xfs/libxfs/xfs_ag.c
Gao Xiang 92a005448f xfs: get rid of unnecessary xfs_perag_{get,put} pairs
In the course of some operations, we look up the perag from
the mount multiple times to get or change perag information.
These are often very short pieces of code, so while the
lookup cost is generally low, the cost of the lookup is far
higher than the cost of the operation we are doing on the
perag.

Since we changed buffers to hold references to the perag
they are cached in, many modification contexts already hold
active references to the perag that are held across these
operations. This is especially true for any operation that
is serialised by an allocation group header buffer.

In these cases, we can just use the buffer's reference to
the perag to avoid needing to do lookups to access the
perag. This means that many operations don't need to do
perag lookups at all to access the perag because they've
already looked up objects that own persistent references
and hence can use that reference instead.

Cc: Dave Chinner <dchinner@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-14 08:47:33 -07:00

592 lines
15 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* Copyright (c) 2018 Red Hat, Inc.
* All rights reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_rmap_btree.h"
#include "xfs_alloc.h"
#include "xfs_ialloc.h"
#include "xfs_rmap.h"
#include "xfs_ag.h"
#include "xfs_ag_resv.h"
#include "xfs_health.h"
static int
xfs_get_aghdr_buf(
struct xfs_mount *mp,
xfs_daddr_t blkno,
size_t numblks,
struct xfs_buf **bpp,
const struct xfs_buf_ops *ops)
{
struct xfs_buf *bp;
int error;
error = xfs_buf_get_uncached(mp->m_ddev_targp, numblks, 0, &bp);
if (error)
return error;
xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
bp->b_bn = blkno;
bp->b_maps[0].bm_bn = blkno;
bp->b_ops = ops;
*bpp = bp;
return 0;
}
static inline bool is_log_ag(struct xfs_mount *mp, struct aghdr_init_data *id)
{
return mp->m_sb.sb_logstart > 0 &&
id->agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
}
/*
* Generic btree root block init function
*/
static void
xfs_btroot_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
xfs_btree_init_block(mp, bp, id->type, 0, 0, id->agno);
}
/* Finish initializing a free space btree. */
static void
xfs_freesp_init_recs(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_alloc_rec *arec;
struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
arec->ar_startblock = cpu_to_be32(mp->m_ag_prealloc_blocks);
if (is_log_ag(mp, id)) {
struct xfs_alloc_rec *nrec;
xfs_agblock_t start = XFS_FSB_TO_AGBNO(mp,
mp->m_sb.sb_logstart);
ASSERT(start >= mp->m_ag_prealloc_blocks);
if (start != mp->m_ag_prealloc_blocks) {
/*
* Modify first record to pad stripe align of log
*/
arec->ar_blockcount = cpu_to_be32(start -
mp->m_ag_prealloc_blocks);
nrec = arec + 1;
/*
* Insert second record at start of internal log
* which then gets trimmed.
*/
nrec->ar_startblock = cpu_to_be32(
be32_to_cpu(arec->ar_startblock) +
be32_to_cpu(arec->ar_blockcount));
arec = nrec;
be16_add_cpu(&block->bb_numrecs, 1);
}
/*
* Change record start to after the internal log
*/
be32_add_cpu(&arec->ar_startblock, mp->m_sb.sb_logblocks);
}
/*
* Calculate the record block count and check for the case where
* the log might have consumed all available space in the AG. If
* so, reset the record count to 0 to avoid exposure of an invalid
* record start block.
*/
arec->ar_blockcount = cpu_to_be32(id->agsize -
be32_to_cpu(arec->ar_startblock));
if (!arec->ar_blockcount)
block->bb_numrecs = 0;
}
/*
* Alloc btree root block init functions
*/
static void
xfs_bnoroot_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
xfs_btree_init_block(mp, bp, XFS_BTNUM_BNO, 0, 1, id->agno);
xfs_freesp_init_recs(mp, bp, id);
}
static void
xfs_cntroot_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
xfs_btree_init_block(mp, bp, XFS_BTNUM_CNT, 0, 1, id->agno);
xfs_freesp_init_recs(mp, bp, id);
}
/*
* Reverse map root block init
*/
static void
xfs_rmaproot_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
struct xfs_rmap_rec *rrec;
xfs_btree_init_block(mp, bp, XFS_BTNUM_RMAP, 0, 4, id->agno);
/*
* mark the AG header regions as static metadata The BNO
* btree block is the first block after the headers, so
* it's location defines the size of region the static
* metadata consumes.
*
* Note: unlike mkfs, we never have to account for log
* space when growing the data regions
*/
rrec = XFS_RMAP_REC_ADDR(block, 1);
rrec->rm_startblock = 0;
rrec->rm_blockcount = cpu_to_be32(XFS_BNO_BLOCK(mp));
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_FS);
rrec->rm_offset = 0;
/* account freespace btree root blocks */
rrec = XFS_RMAP_REC_ADDR(block, 2);
rrec->rm_startblock = cpu_to_be32(XFS_BNO_BLOCK(mp));
rrec->rm_blockcount = cpu_to_be32(2);
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
rrec->rm_offset = 0;
/* account inode btree root blocks */
rrec = XFS_RMAP_REC_ADDR(block, 3);
rrec->rm_startblock = cpu_to_be32(XFS_IBT_BLOCK(mp));
rrec->rm_blockcount = cpu_to_be32(XFS_RMAP_BLOCK(mp) -
XFS_IBT_BLOCK(mp));
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_INOBT);
rrec->rm_offset = 0;
/* account for rmap btree root */
rrec = XFS_RMAP_REC_ADDR(block, 4);
rrec->rm_startblock = cpu_to_be32(XFS_RMAP_BLOCK(mp));
rrec->rm_blockcount = cpu_to_be32(1);
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
rrec->rm_offset = 0;
/* account for refc btree root */
if (xfs_sb_version_hasreflink(&mp->m_sb)) {
rrec = XFS_RMAP_REC_ADDR(block, 5);
rrec->rm_startblock = cpu_to_be32(xfs_refc_block(mp));
rrec->rm_blockcount = cpu_to_be32(1);
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_REFC);
rrec->rm_offset = 0;
be16_add_cpu(&block->bb_numrecs, 1);
}
/* account for the log space */
if (is_log_ag(mp, id)) {
rrec = XFS_RMAP_REC_ADDR(block,
be16_to_cpu(block->bb_numrecs) + 1);
rrec->rm_startblock = cpu_to_be32(
XFS_FSB_TO_AGBNO(mp, mp->m_sb.sb_logstart));
rrec->rm_blockcount = cpu_to_be32(mp->m_sb.sb_logblocks);
rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_LOG);
rrec->rm_offset = 0;
be16_add_cpu(&block->bb_numrecs, 1);
}
}
/*
* Initialise new secondary superblocks with the pre-grow geometry, but mark
* them as "in progress" so we know they haven't yet been activated. This will
* get cleared when the update with the new geometry information is done after
* changes to the primary are committed. This isn't strictly necessary, but we
* get it for free with the delayed buffer write lists and it means we can tell
* if a grow operation didn't complete properly after the fact.
*/
static void
xfs_sbblock_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_dsb *dsb = bp->b_addr;
xfs_sb_to_disk(dsb, &mp->m_sb);
dsb->sb_inprogress = 1;
}
static void
xfs_agfblock_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_agf *agf = bp->b_addr;
xfs_extlen_t tmpsize;
agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
agf->agf_seqno = cpu_to_be32(id->agno);
agf->agf_length = cpu_to_be32(id->agsize);
agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
agf->agf_roots[XFS_BTNUM_RMAPi] =
cpu_to_be32(XFS_RMAP_BLOCK(mp));
agf->agf_levels[XFS_BTNUM_RMAPi] = cpu_to_be32(1);
agf->agf_rmap_blocks = cpu_to_be32(1);
}
agf->agf_flfirst = cpu_to_be32(1);
agf->agf_fllast = 0;
agf->agf_flcount = 0;
tmpsize = id->agsize - mp->m_ag_prealloc_blocks;
agf->agf_freeblks = cpu_to_be32(tmpsize);
agf->agf_longest = cpu_to_be32(tmpsize);
if (xfs_sb_version_hascrc(&mp->m_sb))
uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
if (xfs_sb_version_hasreflink(&mp->m_sb)) {
agf->agf_refcount_root = cpu_to_be32(
xfs_refc_block(mp));
agf->agf_refcount_level = cpu_to_be32(1);
agf->agf_refcount_blocks = cpu_to_be32(1);
}
if (is_log_ag(mp, id)) {
int64_t logblocks = mp->m_sb.sb_logblocks;
be32_add_cpu(&agf->agf_freeblks, -logblocks);
agf->agf_longest = cpu_to_be32(id->agsize -
XFS_FSB_TO_AGBNO(mp, mp->m_sb.sb_logstart) - logblocks);
}
}
static void
xfs_agflblock_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_agfl *agfl = XFS_BUF_TO_AGFL(bp);
__be32 *agfl_bno;
int bucket;
if (xfs_sb_version_hascrc(&mp->m_sb)) {
agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
agfl->agfl_seqno = cpu_to_be32(id->agno);
uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid);
}
agfl_bno = xfs_buf_to_agfl_bno(bp);
for (bucket = 0; bucket < xfs_agfl_size(mp); bucket++)
agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
}
static void
xfs_agiblock_init(
struct xfs_mount *mp,
struct xfs_buf *bp,
struct aghdr_init_data *id)
{
struct xfs_agi *agi = bp->b_addr;
int bucket;
agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
agi->agi_seqno = cpu_to_be32(id->agno);
agi->agi_length = cpu_to_be32(id->agsize);
agi->agi_count = 0;
agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
agi->agi_level = cpu_to_be32(1);
agi->agi_freecount = 0;
agi->agi_newino = cpu_to_be32(NULLAGINO);
agi->agi_dirino = cpu_to_be32(NULLAGINO);
if (xfs_sb_version_hascrc(&mp->m_sb))
uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
agi->agi_free_root = cpu_to_be32(XFS_FIBT_BLOCK(mp));
agi->agi_free_level = cpu_to_be32(1);
}
for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
}
typedef void (*aghdr_init_work_f)(struct xfs_mount *mp, struct xfs_buf *bp,
struct aghdr_init_data *id);
static int
xfs_ag_init_hdr(
struct xfs_mount *mp,
struct aghdr_init_data *id,
aghdr_init_work_f work,
const struct xfs_buf_ops *ops)
{
struct xfs_buf *bp;
int error;
error = xfs_get_aghdr_buf(mp, id->daddr, id->numblks, &bp, ops);
if (error)
return error;
(*work)(mp, bp, id);
xfs_buf_delwri_queue(bp, &id->buffer_list);
xfs_buf_relse(bp);
return 0;
}
struct xfs_aghdr_grow_data {
xfs_daddr_t daddr;
size_t numblks;
const struct xfs_buf_ops *ops;
aghdr_init_work_f work;
xfs_btnum_t type;
bool need_init;
};
/*
* Prepare new AG headers to be written to disk. We use uncached buffers here,
* as it is assumed these new AG headers are currently beyond the currently
* valid filesystem address space. Using cached buffers would trip over EOFS
* corruption detection alogrithms in the buffer cache lookup routines.
*
* This is a non-transactional function, but the prepared buffers are added to a
* delayed write buffer list supplied by the caller so they can submit them to
* disk and wait on them as required.
*/
int
xfs_ag_init_headers(
struct xfs_mount *mp,
struct aghdr_init_data *id)
{
struct xfs_aghdr_grow_data aghdr_data[] = {
{ /* SB */
.daddr = XFS_AG_DADDR(mp, id->agno, XFS_SB_DADDR),
.numblks = XFS_FSS_TO_BB(mp, 1),
.ops = &xfs_sb_buf_ops,
.work = &xfs_sbblock_init,
.need_init = true
},
{ /* AGF */
.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGF_DADDR(mp)),
.numblks = XFS_FSS_TO_BB(mp, 1),
.ops = &xfs_agf_buf_ops,
.work = &xfs_agfblock_init,
.need_init = true
},
{ /* AGFL */
.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGFL_DADDR(mp)),
.numblks = XFS_FSS_TO_BB(mp, 1),
.ops = &xfs_agfl_buf_ops,
.work = &xfs_agflblock_init,
.need_init = true
},
{ /* AGI */
.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGI_DADDR(mp)),
.numblks = XFS_FSS_TO_BB(mp, 1),
.ops = &xfs_agi_buf_ops,
.work = &xfs_agiblock_init,
.need_init = true
},
{ /* BNO root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_BNO_BLOCK(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_bnobt_buf_ops,
.work = &xfs_bnoroot_init,
.need_init = true
},
{ /* CNT root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_CNT_BLOCK(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_cntbt_buf_ops,
.work = &xfs_cntroot_init,
.need_init = true
},
{ /* INO root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_IBT_BLOCK(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_inobt_buf_ops,
.work = &xfs_btroot_init,
.type = XFS_BTNUM_INO,
.need_init = true
},
{ /* FINO root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_FIBT_BLOCK(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_finobt_buf_ops,
.work = &xfs_btroot_init,
.type = XFS_BTNUM_FINO,
.need_init = xfs_sb_version_hasfinobt(&mp->m_sb)
},
{ /* RMAP root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_RMAP_BLOCK(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_rmapbt_buf_ops,
.work = &xfs_rmaproot_init,
.need_init = xfs_sb_version_hasrmapbt(&mp->m_sb)
},
{ /* REFC root block */
.daddr = XFS_AGB_TO_DADDR(mp, id->agno, xfs_refc_block(mp)),
.numblks = BTOBB(mp->m_sb.sb_blocksize),
.ops = &xfs_refcountbt_buf_ops,
.work = &xfs_btroot_init,
.type = XFS_BTNUM_REFC,
.need_init = xfs_sb_version_hasreflink(&mp->m_sb)
},
{ /* NULL terminating block */
.daddr = XFS_BUF_DADDR_NULL,
}
};
struct xfs_aghdr_grow_data *dp;
int error = 0;
/* Account for AG free space in new AG */
id->nfree += id->agsize - mp->m_ag_prealloc_blocks;
for (dp = &aghdr_data[0]; dp->daddr != XFS_BUF_DADDR_NULL; dp++) {
if (!dp->need_init)
continue;
id->daddr = dp->daddr;
id->numblks = dp->numblks;
id->type = dp->type;
error = xfs_ag_init_hdr(mp, id, dp->work, dp->ops);
if (error)
break;
}
return error;
}
/*
* Extent the AG indicated by the @id by the length passed in
*/
int
xfs_ag_extend_space(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct aghdr_init_data *id,
xfs_extlen_t len)
{
struct xfs_buf *bp;
struct xfs_agi *agi;
struct xfs_agf *agf;
int error;
/*
* Change the agi length.
*/
error = xfs_ialloc_read_agi(mp, tp, id->agno, &bp);
if (error)
return error;
agi = bp->b_addr;
be32_add_cpu(&agi->agi_length, len);
ASSERT(id->agno == mp->m_sb.sb_agcount - 1 ||
be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
/*
* Change agf length.
*/
error = xfs_alloc_read_agf(mp, tp, id->agno, 0, &bp);
if (error)
return error;
agf = bp->b_addr;
be32_add_cpu(&agf->agf_length, len);
ASSERT(agf->agf_length == agi->agi_length);
xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
/*
* Free the new space.
*
* XFS_RMAP_OINFO_SKIP_UPDATE is used here to tell the rmap btree that
* this doesn't actually exist in the rmap btree.
*/
error = xfs_rmap_free(tp, bp, id->agno,
be32_to_cpu(agf->agf_length) - len,
len, &XFS_RMAP_OINFO_SKIP_UPDATE);
if (error)
return error;
return xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, id->agno,
be32_to_cpu(agf->agf_length) - len),
len, &XFS_RMAP_OINFO_SKIP_UPDATE,
XFS_AG_RESV_NONE);
}
/* Retrieve AG geometry. */
int
xfs_ag_get_geometry(
struct xfs_mount *mp,
xfs_agnumber_t agno,
struct xfs_ag_geometry *ageo)
{
struct xfs_buf *agi_bp;
struct xfs_buf *agf_bp;
struct xfs_agi *agi;
struct xfs_agf *agf;
struct xfs_perag *pag;
unsigned int freeblks;
int error;
if (agno >= mp->m_sb.sb_agcount)
return -EINVAL;
/* Lock the AG headers. */
error = xfs_ialloc_read_agi(mp, NULL, agno, &agi_bp);
if (error)
return error;
error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agf_bp);
if (error)
goto out_agi;
pag = agi_bp->b_pag;
/* Fill out form. */
memset(ageo, 0, sizeof(*ageo));
ageo->ag_number = agno;
agi = agi_bp->b_addr;
ageo->ag_icount = be32_to_cpu(agi->agi_count);
ageo->ag_ifree = be32_to_cpu(agi->agi_freecount);
agf = agf_bp->b_addr;
ageo->ag_length = be32_to_cpu(agf->agf_length);
freeblks = pag->pagf_freeblks +
pag->pagf_flcount +
pag->pagf_btreeblks -
xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE);
ageo->ag_freeblks = freeblks;
xfs_ag_geom_health(pag, ageo);
/* Release resources. */
xfs_buf_relse(agf_bp);
out_agi:
xfs_buf_relse(agi_bp);
return error;
}