linux/fs/xfs/libxfs/xfs_sb.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_error.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_log.h"
#include "xfs_rmap_btree.h"
#include "xfs_refcount_btree.h"
#include "xfs_da_format.h"
#include "xfs_health.h"
#include "xfs_ag.h"
#include "xfs_rtbitmap.h"
#include "xfs_exchrange.h"

/*
 * Physical superblock buffer manipulations. Shared with libxfs in userspace.
 */

/*
 * Check that all the V4 feature bits that the V5 filesystem format requires are
 * correctly set.
 */
static bool
xfs_sb_validate_v5_features(
	struct xfs_sb	*sbp)
{ … }

/*
 * We current support XFS v5 formats with known features and v4 superblocks with
 * at least V2 directories.
 */
bool
xfs_sb_good_version(
	struct xfs_sb	*sbp)
{ … }

uint64_t
xfs_sb_version_to_features(
	struct xfs_sb	*sbp)
{ … }

/* Check all the superblock fields we care about when reading one in. */
STATIC int
xfs_validate_sb_read(
	struct xfs_mount	*mp,
	struct xfs_sb		*sbp)
{ … }

static uint64_t
xfs_sb_calc_rbmblocks(
	struct xfs_sb		*sbp)
{ … }

/* Validate the realtime geometry */
bool
xfs_validate_rt_geometry(
	struct xfs_sb		*sbp)
{ … }

/* Check all the superblock fields we care about when writing one out. */
STATIC int
xfs_validate_sb_write(
	struct xfs_mount	*mp,
	struct xfs_buf		*bp,
	struct xfs_sb		*sbp)
{ … }

/* Check the validity of the SB. */
STATIC int
xfs_validate_sb_common(
	struct xfs_mount	*mp,
	struct xfs_buf		*bp,
	struct xfs_sb		*sbp)
{ … }

void
xfs_sb_quota_from_disk(struct xfs_sb *sbp)
{ … }

static void
__xfs_sb_from_disk(
	struct xfs_sb	*to,
	struct xfs_dsb	*from,
	bool		convert_xquota)
{ … }

void
xfs_sb_from_disk(
	struct xfs_sb	*to,
	struct xfs_dsb	*from)
{ … }

static void
xfs_sb_quota_to_disk(
	struct xfs_dsb	*to,
	struct xfs_sb	*from)
{ … }

void
xfs_sb_to_disk(
	struct xfs_dsb	*to,
	struct xfs_sb	*from)
{ … }

/*
 * If the superblock has the CRC feature bit set or the CRC field is non-null,
 * check that the CRC is valid.  We check the CRC field is non-null because a
 * single bit error could clear the feature bit and unused parts of the
 * superblock are supposed to be zero. Hence a non-null crc field indicates that
 * we've potentially lost a feature bit and we should check it anyway.
 *
 * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the
 * last field in V4 secondary superblocks.  So for secondary superblocks,
 * we are more forgiving, and ignore CRC failures if the primary doesn't
 * indicate that the fs version is V5.
 */
static void
xfs_sb_read_verify(
	struct xfs_buf		*bp)
{ … }

/*
 * We may be probed for a filesystem match, so we may not want to emit
 * messages when the superblock buffer is not actually an XFS superblock.
 * If we find an XFS superblock, then run a normal, noisy mount because we are
 * really going to mount it and want to know about errors.
 */
static void
xfs_sb_quiet_read_verify(
	struct xfs_buf	*bp)
{ … }

static void
xfs_sb_write_verify(
	struct xfs_buf		*bp)
{ … }

const struct xfs_buf_ops xfs_sb_buf_ops = …;

const struct xfs_buf_ops xfs_sb_quiet_buf_ops = …;

void
xfs_mount_sb_set_rextsize(
	struct xfs_mount	*mp,
	struct xfs_sb		*sbp)
{ … }

/*
 * xfs_mount_common
 *
 * Mount initialization code establishing various mount
 * fields from the superblock associated with the given
 * mount structure.
 *
 * Inode geometry are calculated in xfs_ialloc_setup_geometry.
 */
void
xfs_sb_mount_common(
	struct xfs_mount	*mp,
	struct xfs_sb		*sbp)
{ … }

/*
 * xfs_log_sb() can be used to copy arbitrary changes to the in-core superblock
 * into the superblock buffer to be logged.  It does not provide the higher
 * level of locking that is needed to protect the in-core superblock from
 * concurrent access.
 */
void
xfs_log_sb(
	struct xfs_trans	*tp)
{ … }

/*
 * xfs_sync_sb
 *
 * Sync the superblock to disk.
 *
 * Note that the caller is responsible for checking the frozen state of the
 * filesystem. This procedure uses the non-blocking transaction allocator and
 * thus will allow modifications to a frozen fs. This is required because this
 * code can be called during the process of freezing where use of the high-level
 * allocator would deadlock.
 */
int
xfs_sync_sb(
	struct xfs_mount	*mp,
	bool			wait)
{ … }

/*
 * Update all the secondary superblocks to match the new state of the primary.
 * Because we are completely overwriting all the existing fields in the
 * secondary superblock buffers, there is no need to read them in from disk.
 * Just get a new buffer, stamp it and write it.
 *
 * The sb buffers need to be cached here so that we serialise against other
 * operations that access the secondary superblocks, but we don't want to keep
 * them in memory once it is written so we mark it as a one-shot buffer.
 */
int
xfs_update_secondary_sbs(
	struct xfs_mount	*mp)
{ … }

/*
 * Same behavior as xfs_sync_sb, except that it is always synchronous and it
 * also writes the superblock buffer to disk sector 0 immediately.
 */
int
xfs_sync_sb_buf(
	struct xfs_mount	*mp)
{ … }

void
xfs_fs_geometry(
	struct xfs_mount	*mp,
	struct xfs_fsop_geom	*geo,
	int			struct_version)
{ … }

/* Read a secondary superblock. */
int
xfs_sb_read_secondary(
	struct xfs_mount	*mp,
	struct xfs_trans	*tp,
	xfs_agnumber_t		agno,
	struct xfs_buf		**bpp)
{ … }

/* Get an uninitialised secondary superblock buffer. */
int
xfs_sb_get_secondary(
	struct xfs_mount	*mp,
	struct xfs_trans	*tp,
	xfs_agnumber_t		agno,
	struct xfs_buf		**bpp)
{ … }

/*
 * sunit, swidth, sectorsize(optional with 0) should be all in bytes, so users
 * won't be confused by values in error messages.  This function returns false
 * if the stripe geometry is invalid and the caller is unable to repair the
 * stripe configuration later in the mount process.
 */
bool
xfs_validate_stripe_geometry(
	struct xfs_mount	*mp,
	__s64			sunit,
	__s64			swidth,
	int			sectorsize,
	bool			may_repair,
	bool			silent)
{ … }

/*
 * Compute the maximum level number of the realtime summary file, as defined by
 * mkfs.  The historic use of highbit32 on a 64-bit quantity prohibited correct
 * use of rt volumes with more than 2^32 extents.
 */
uint8_t
xfs_compute_rextslog(
	xfs_rtbxlen_t		rtextents)
{ … }