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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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_inode.h"
 #include "xfs_dir2.h"
 #include "xfs_ialloc.h"
 #include "xfs_alloc.h"
 #include "xfs_rtalloc.h"
 #include "xfs_bmap.h"
 #include "xfs_trans.h"
 #include "xfs_trans_priv.h"
 #include "xfs_log.h"
 #include "xfs_log_priv.h"
 #include "xfs_error.h"
 #include "xfs_quota.h"
 #include "xfs_fsops.h"
 #include "xfs_icache.h"
 #include "xfs_sysfs.h"
 #include "xfs_rmap_btree.h"
 #include "xfs_refcount_btree.h"
 #include "xfs_reflink.h"
 #include "xfs_extent_busy.h"
 #include "xfs_health.h"
 #include "xfs_trace.h"
 #include "xfs_ag.h"
 
 static DEFINE_MUTEX(xfs_uuid_table_mutex);
 static int xfs_uuid_table_size;
 static uuid_t *xfs_uuid_table;
 
 void
 xfs_uuid_table_free(void)
 {
     if (xfs_uuid_table_size == 0)
         return;
     kmem_free(xfs_uuid_table);
     xfs_uuid_table = NULL;
     xfs_uuid_table_size = 0;
 }
 
 /*
  * See if the UUID is unique among mounted XFS filesystems.
  * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
  */
 STATIC int
 xfs_uuid_mount(
     struct xfs_mount    *mp)
 {
     uuid_t          *uuid = &mp->m_sb.sb_uuid;
     int         hole, i;
 
     /* Publish UUID in struct super_block */
     uuid_copy(&mp->m_super->s_uuid, uuid);
 
     if (xfs_has_nouuid(mp))
         return 0;
 
     if (uuid_is_null(uuid)) {
         xfs_warn(mp, "Filesystem has null UUID - can't mount");
         return -EINVAL;
     }
 
     mutex_lock(&xfs_uuid_table_mutex);
     for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
         if (uuid_is_null(&xfs_uuid_table[i])) {
             hole = i;
             continue;
         }
         if (uuid_equal(uuid, &xfs_uuid_table[i]))
             goto out_duplicate;
     }
 
     if (hole < 0) {
         xfs_uuid_table = krealloc(xfs_uuid_table,
             (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
             GFP_KERNEL | __GFP_NOFAIL);
         hole = xfs_uuid_table_size++;
     }
     xfs_uuid_table[hole] = *uuid;
     mutex_unlock(&xfs_uuid_table_mutex);
 
     return 0;
 
  out_duplicate:
     mutex_unlock(&xfs_uuid_table_mutex);
     xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
     return -EINVAL;
 }
 
 STATIC void
 xfs_uuid_unmount(
     struct xfs_mount    *mp)
 {
     uuid_t          *uuid = &mp->m_sb.sb_uuid;
     int         i;
 
     if (xfs_has_nouuid(mp))
         return;
 
     mutex_lock(&xfs_uuid_table_mutex);
     for (i = 0; i < xfs_uuid_table_size; i++) {
         if (uuid_is_null(&xfs_uuid_table[i]))
             continue;
         if (!uuid_equal(uuid, &xfs_uuid_table[i]))
             continue;
         memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
         break;
     }
     ASSERT(i < xfs_uuid_table_size);
     mutex_unlock(&xfs_uuid_table_mutex);
 }
 
 /*
  * Check size of device based on the (data/realtime) block count.
  * Note: this check is used by the growfs code as well as mount.
  */
 int
 xfs_sb_validate_fsb_count(
     xfs_sb_t    *sbp,
     uint64_t    nblocks)
 {
     ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
     ASSERT(sbp->sb_blocklog >= BBSHIFT);
 
     /* Limited by ULONG_MAX of page cache index */
     if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
         return -EFBIG;
     return 0;
 }
 
 /*
  * xfs_readsb
  *
  * Does the initial read of the superblock.
  */
 int
 xfs_readsb(
     struct xfs_mount *mp,
     int     flags)
 {
     unsigned int    sector_size;
     struct xfs_buf  *bp;
     struct xfs_sb   *sbp = &mp->m_sb;
     int     error;
     int     loud = !(flags & XFS_MFSI_QUIET);
     const struct xfs_buf_ops *buf_ops;
 
     ASSERT(mp->m_sb_bp == NULL);
     ASSERT(mp->m_ddev_targp != NULL);
 
     /*
      * For the initial read, we must guess at the sector
      * size based on the block device.  It's enough to
      * get the sb_sectsize out of the superblock and
      * then reread with the proper length.
      * We don't verify it yet, because it may not be complete.
      */
     sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
     buf_ops = NULL;
 
     /*
      * Allocate a (locked) buffer to hold the superblock. This will be kept
      * around at all times to optimize access to the superblock. Therefore,
      * set XBF_NO_IOACCT to make sure it doesn't hold the buftarg count
      * elevated.
      */
 reread:
     error = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
                       BTOBB(sector_size), XBF_NO_IOACCT, &bp,
                       buf_ops);
     if (error) {
         if (loud)
             xfs_warn(mp, "SB validate failed with error %d.", error);
         /* bad CRC means corrupted metadata */
         if (error == -EFSBADCRC)
             error = -EFSCORRUPTED;
         return error;
     }
 
     /*
      * Initialize the mount structure from the superblock.
      */
     xfs_sb_from_disk(sbp, bp->b_addr);
 
     /*
      * If we haven't validated the superblock, do so now before we try
      * to check the sector size and reread the superblock appropriately.
      */
     if (sbp->sb_magicnum != XFS_SB_MAGIC) {
         if (loud)
             xfs_warn(mp, "Invalid superblock magic number");
         error = -EINVAL;
         goto release_buf;
     }
 
     /*
      * We must be able to do sector-sized and sector-aligned IO.
      */
     if (sector_size > sbp->sb_sectsize) {
         if (loud)
             xfs_warn(mp, "device supports %u byte sectors (not %u)",
                 sector_size, sbp->sb_sectsize);
         error = -ENOSYS;
         goto release_buf;
     }
 
     if (buf_ops == NULL) {
         /*
          * Re-read the superblock so the buffer is correctly sized,
          * and properly verified.
          */
         xfs_buf_relse(bp);
         sector_size = sbp->sb_sectsize;
         buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
         goto reread;
     }
 
     mp->m_features |= xfs_sb_version_to_features(sbp);
     xfs_reinit_percpu_counters(mp);
 
     /* no need to be quiet anymore, so reset the buf ops */
     bp->b_ops = &xfs_sb_buf_ops;
 
     mp->m_sb_bp = bp;
     xfs_buf_unlock(bp);
     return 0;
 
 release_buf:
     xfs_buf_relse(bp);
     return error;
 }
 
 /*
  * If the sunit/swidth change would move the precomputed root inode value, we
  * must reject the ondisk change because repair will stumble over that.
  * However, we allow the mount to proceed because we never rejected this
  * combination before.  Returns true to update the sb, false otherwise.
  */
 static inline int
 xfs_check_new_dalign(
     struct xfs_mount    *mp,
     int         new_dalign,
     bool            *update_sb)
 {
     struct xfs_sb       *sbp = &mp->m_sb;
     xfs_ino_t       calc_ino;
 
     calc_ino = xfs_ialloc_calc_rootino(mp, new_dalign);
     trace_xfs_check_new_dalign(mp, new_dalign, calc_ino);
 
     if (sbp->sb_rootino == calc_ino) {
         *update_sb = true;
         return 0;
     }
 
     xfs_warn(mp,
 "Cannot change stripe alignment; would require moving root inode.");
 
     /*
      * XXX: Next time we add a new incompat feature, this should start
      * returning -EINVAL to fail the mount.  Until then, spit out a warning
      * that we're ignoring the administrator's instructions.
      */
     xfs_warn(mp, "Skipping superblock stripe alignment update.");
     *update_sb = false;
     return 0;
 }
 
 /*
  * If we were provided with new sunit/swidth values as mount options, make sure
  * that they pass basic alignment and superblock feature checks, and convert
  * them into the same units (FSB) that everything else expects.  This step
  * /must/ be done before computing the inode geometry.
  */
 STATIC int
 xfs_validate_new_dalign(
     struct xfs_mount    *mp)
 {
     if (mp->m_dalign == 0)
         return 0;
 
     /*
      * If stripe unit and stripe width are not multiples
      * of the fs blocksize turn off alignment.
      */
     if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
         (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
         xfs_warn(mp,
     "alignment check failed: sunit/swidth vs. blocksize(%d)",
             mp->m_sb.sb_blocksize);
         return -EINVAL;
     } else {
         /*
          * Convert the stripe unit and width to FSBs.
          */
         mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
         if (mp->m_dalign && (mp->m_sb.sb_agblocks % mp->m_dalign)) {
             xfs_warn(mp,
         "alignment check failed: sunit/swidth vs. agsize(%d)",
                  mp->m_sb.sb_agblocks);
             return -EINVAL;
         } else if (mp->m_dalign) {
             mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
         } else {
             xfs_warn(mp,
         "alignment check failed: sunit(%d) less than bsize(%d)",
                  mp->m_dalign, mp->m_sb.sb_blocksize);
             return -EINVAL;
         }
     }
 
     if (!xfs_has_dalign(mp)) {
         xfs_warn(mp,
 "cannot change alignment: superblock does not support data alignment");
         return -EINVAL;
     }
 
     return 0;
 }
 
 /* Update alignment values based on mount options and sb values. */
 STATIC int
 xfs_update_alignment(
     struct xfs_mount    *mp)
 {
     struct xfs_sb       *sbp = &mp->m_sb;
 
     if (mp->m_dalign) {
         bool        update_sb;
         int     error;
 
         if (sbp->sb_unit == mp->m_dalign &&
             sbp->sb_width == mp->m_swidth)
             return 0;
 
         error = xfs_check_new_dalign(mp, mp->m_dalign, &update_sb);
         if (error || !update_sb)
             return error;
 
         sbp->sb_unit = mp->m_dalign;
         sbp->sb_width = mp->m_swidth;
         mp->m_update_sb = true;
     } else if (!xfs_has_noalign(mp) && xfs_has_dalign(mp)) {
         mp->m_dalign = sbp->sb_unit;
         mp->m_swidth = sbp->sb_width;
     }
 
     return 0;
 }
 
 /*
  * precalculate the low space thresholds for dynamic speculative preallocation.
  */
 void
 xfs_set_low_space_thresholds(
     struct xfs_mount    *mp)
 {
     uint64_t        dblocks = mp->m_sb.sb_dblocks;
     uint64_t        rtexts = mp->m_sb.sb_rextents;
     int         i;
 
     do_div(dblocks, 100);
     do_div(rtexts, 100);
 
     for (i = 0; i < XFS_LOWSP_MAX; i++) {
         mp->m_low_space[i] = dblocks * (i + 1);
         mp->m_low_rtexts[i] = rtexts * (i + 1);
     }
 }
 
 /*
  * Check that the data (and log if separate) is an ok size.
  */
 STATIC int
 xfs_check_sizes(
     struct xfs_mount *mp)
 {
     struct xfs_buf  *bp;
     xfs_daddr_t d;
     int     error;
 
     d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
     if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
         xfs_warn(mp, "filesystem size mismatch detected");
         return -EFBIG;
     }
     error = xfs_buf_read_uncached(mp->m_ddev_targp,
                     d - XFS_FSS_TO_BB(mp, 1),
                     XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
     if (error) {
         xfs_warn(mp, "last sector read failed");
         return error;
     }
     xfs_buf_relse(bp);
 
     if (mp->m_logdev_targp == mp->m_ddev_targp)
         return 0;
 
     d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
     if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
         xfs_warn(mp, "log size mismatch detected");
         return -EFBIG;
     }
     error = xfs_buf_read_uncached(mp->m_logdev_targp,
                     d - XFS_FSB_TO_BB(mp, 1),
                     XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
     if (error) {
         xfs_warn(mp, "log device read failed");
         return error;
     }
     xfs_buf_relse(bp);
     return 0;
 }
 
 /*
  * Clear the quotaflags in memory and in the superblock.
  */
 int
 xfs_mount_reset_sbqflags(
     struct xfs_mount    *mp)
 {
     mp->m_qflags = 0;
 
     /* It is OK to look at sb_qflags in the mount path without m_sb_lock. */
     if (mp->m_sb.sb_qflags == 0)
         return 0;
     spin_lock(&mp->m_sb_lock);
     mp->m_sb.sb_qflags = 0;
     spin_unlock(&mp->m_sb_lock);
 
     if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
         return 0;
 
     return xfs_sync_sb(mp, false);
 }
 
 uint64_t
 xfs_default_resblks(xfs_mount_t *mp)
 {
     uint64_t resblks;
 
     /*
      * We default to 5% or 8192 fsbs of space reserved, whichever is
      * smaller.  This is intended to cover concurrent allocation
      * transactions when we initially hit enospc. These each require a 4
      * block reservation. Hence by default we cover roughly 2000 concurrent
      * allocation reservations.
      */
     resblks = mp->m_sb.sb_dblocks;
     do_div(resblks, 20);
     resblks = min_t(uint64_t, resblks, 8192);
     return resblks;
 }
 
 /* Ensure the summary counts are correct. */
 STATIC int
 xfs_check_summary_counts(
     struct xfs_mount    *mp)
 {
     int         error = 0;
 
     /*
      * The AG0 superblock verifier rejects in-progress filesystems,
      * so we should never see the flag set this far into mounting.
      */
     if (mp->m_sb.sb_inprogress) {
         xfs_err(mp, "sb_inprogress set after log recovery??");
         WARN_ON(1);
         return -EFSCORRUPTED;
     }
 
     /*
      * Now the log is mounted, we know if it was an unclean shutdown or
      * not. If it was, with the first phase of recovery has completed, we
      * have consistent AG blocks on disk. We have not recovered EFIs yet,
      * but they are recovered transactionally in the second recovery phase
      * later.
      *
      * If the log was clean when we mounted, we can check the summary
      * counters.  If any of them are obviously incorrect, we can recompute
      * them from the AGF headers in the next step.
      */
     if (xfs_is_clean(mp) &&
         (mp->m_sb.sb_fdblocks > mp->m_sb.sb_dblocks ||
          !xfs_verify_icount(mp, mp->m_sb.sb_icount) ||
          mp->m_sb.sb_ifree > mp->m_sb.sb_icount))
         xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
 
     /*
      * We can safely re-initialise incore superblock counters from the
      * per-ag data. These may not be correct if the filesystem was not
      * cleanly unmounted, so we waited for recovery to finish before doing
      * this.
      *
      * If the filesystem was cleanly unmounted or the previous check did
      * not flag anything weird, then we can trust the values in the
      * superblock to be correct and we don't need to do anything here.
      * Otherwise, recalculate the summary counters.
      */
     if ((xfs_has_lazysbcount(mp) && !xfs_is_clean(mp)) ||
         xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS)) {
         error = xfs_initialize_perag_data(mp, mp->m_sb.sb_agcount);
         if (error)
             return error;
     }
 
     /*
      * Older kernels misused sb_frextents to reflect both incore
      * reservations made by running transactions and the actual count of
      * free rt extents in the ondisk metadata.  Transactions committed
      * during runtime can therefore contain a superblock update that
      * undercounts the number of free rt extents tracked in the rt bitmap.
      * A clean unmount record will have the correct frextents value since
      * there can be no other transactions running at that point.
      *
      * If we're mounting the rt volume after recovering the log, recompute
      * frextents from the rtbitmap file to fix the inconsistency.
      */
     if (xfs_has_realtime(mp) && !xfs_is_clean(mp)) {
         error = xfs_rtalloc_reinit_frextents(mp);
         if (error)
             return error;
     }
 
     return 0;
 }
 
 /*
  * Flush and reclaim dirty inodes in preparation for unmount. Inodes and
  * internal inode structures can be sitting in the CIL and AIL at this point,
  * so we need to unpin them, write them back and/or reclaim them before unmount
  * can proceed.  In other words, callers are required to have inactivated all
  * inodes.
  *
  * An inode cluster that has been freed can have its buffer still pinned in
  * memory because the transaction is still sitting in a iclog. The stale inodes
  * on that buffer will be pinned to the buffer until the transaction hits the
  * disk and the callbacks run. Pushing the AIL will skip the stale inodes and
  * may never see the pinned buffer, so nothing will push out the iclog and
  * unpin the buffer.
  *
  * Hence we need to force the log to unpin everything first. However, log
  * forces don't wait for the discards they issue to complete, so we have to
  * explicitly wait for them to complete here as well.
  *
  * Then we can tell the world we are unmounting so that error handling knows
  * that the filesystem is going away and we should error out anything that we
  * have been retrying in the background.  This will prevent never-ending
  * retries in AIL pushing from hanging the unmount.
  *
  * Finally, we can push the AIL to clean all the remaining dirty objects, then
  * reclaim the remaining inodes that are still in memory at this point in time.
  */
 static void
 xfs_unmount_flush_inodes(
     struct xfs_mount    *mp)
 {
     xfs_log_force(mp, XFS_LOG_SYNC);
     xfs_extent_busy_wait_all(mp);
     flush_workqueue(xfs_discard_wq);
 
     set_bit(XFS_OPSTATE_UNMOUNTING, &mp->m_opstate);
 
     xfs_ail_push_all_sync(mp->m_ail);
     xfs_inodegc_stop(mp);
     cancel_delayed_work_sync(&mp->m_reclaim_work);
     xfs_reclaim_inodes(mp);
     xfs_health_unmount(mp);
 }
 
 static void
 xfs_mount_setup_inode_geom(
     struct xfs_mount    *mp)
 {
     struct xfs_ino_geometry *igeo = M_IGEO(mp);
 
     igeo->attr_fork_offset = xfs_bmap_compute_attr_offset(mp);
     ASSERT(igeo->attr_fork_offset < XFS_LITINO(mp));
 
     xfs_ialloc_setup_geometry(mp);
 }
 
 /* Compute maximum possible height for per-AG btree types for this fs. */
 static inline void
 xfs_agbtree_compute_maxlevels(
     struct xfs_mount    *mp)
 {
     unsigned int        levels;
 
     levels = max(mp->m_alloc_maxlevels, M_IGEO(mp)->inobt_maxlevels);
     levels = max(levels, mp->m_rmap_maxlevels);
     mp->m_agbtree_maxlevels = max(levels, mp->m_refc_maxlevels);
 }
 
 /*
  * This function does the following on an initial mount of a file system:
  *  - reads the superblock from disk and init the mount struct
  *  - if we're a 32-bit kernel, do a size check on the superblock
  *      so we don't mount terabyte filesystems
  *  - init mount struct realtime fields
  *  - allocate inode hash table for fs
  *  - init directory manager
  *  - perform recovery and init the log manager
  */
 int
 xfs_mountfs(
     struct xfs_mount    *mp)
 {
     struct xfs_sb       *sbp = &(mp->m_sb);
     struct xfs_inode    *rip;
     struct xfs_ino_geometry *igeo = M_IGEO(mp);
     uint64_t        resblks;
     uint            quotamount = 0;
     uint            quotaflags = 0;
     int         error = 0;
 
     xfs_sb_mount_common(mp, sbp);
 
     /*
      * Check for a mismatched features2 values.  Older kernels read & wrote
      * into the wrong sb offset for sb_features2 on some platforms due to
      * xfs_sb_t not being 64bit size aligned when sb_features2 was added,
      * which made older superblock reading/writing routines swap it as a
      * 64-bit value.
      *
      * For backwards compatibility, we make both slots equal.
      *
      * If we detect a mismatched field, we OR the set bits into the existing
      * features2 field in case it has already been modified; we don't want
      * to lose any features.  We then update the bad location with the ORed
      * value so that older kernels will see any features2 flags. The
      * superblock writeback code ensures the new sb_features2 is copied to
      * sb_bad_features2 before it is logged or written to disk.
      */
     if (xfs_sb_has_mismatched_features2(sbp)) {
         xfs_warn(mp, "correcting sb_features alignment problem");
         sbp->sb_features2 |= sbp->sb_bad_features2;
         mp->m_update_sb = true;
     }
 
 
     /* always use v2 inodes by default now */
     if (!(mp->m_sb.sb_versionnum & XFS_SB_VERSION_NLINKBIT)) {
         mp->m_sb.sb_versionnum |= XFS_SB_VERSION_NLINKBIT;
         mp->m_features |= XFS_FEAT_NLINK;
         mp->m_update_sb = true;
     }
 
     /*
      * If we were given new sunit/swidth options, do some basic validation
      * checks and convert the incore dalign and swidth values to the
      * same units (FSB) that everything else uses.  This /must/ happen
      * before computing the inode geometry.
      */
     error = xfs_validate_new_dalign(mp);
     if (error)
         goto out;
 
     xfs_alloc_compute_maxlevels(mp);
     xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
     xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
     xfs_mount_setup_inode_geom(mp);
     xfs_rmapbt_compute_maxlevels(mp);
     xfs_refcountbt_compute_maxlevels(mp);
 
     xfs_agbtree_compute_maxlevels(mp);
 
     /*
      * Check if sb_agblocks is aligned at stripe boundary.  If sb_agblocks
      * is NOT aligned turn off m_dalign since allocator alignment is within
      * an ag, therefore ag has to be aligned at stripe boundary.  Note that
      * we must compute the free space and rmap btree geometry before doing
      * this.
      */
     error = xfs_update_alignment(mp);
     if (error)
         goto out;
 
     /* enable fail_at_unmount as default */
     mp->m_fail_unmount = true;
 
     error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype,
                    NULL, mp->m_super->s_id);
     if (error)
         goto out;
 
     error = xfs_sysfs_init(&mp->m_stats.xs_kobj, &xfs_stats_ktype,
                    &mp->m_kobj, "stats");
     if (error)
         goto out_remove_sysfs;
 
     error = xfs_error_sysfs_init(mp);
     if (error)
         goto out_del_stats;
 
     error = xfs_errortag_init(mp);
     if (error)
         goto out_remove_error_sysfs;
 
     error = xfs_uuid_mount(mp);
     if (error)
         goto out_remove_errortag;
 
     /*
      * Update the preferred write size based on the information from the
      * on-disk superblock.
      */
     mp->m_allocsize_log =
         max_t(uint32_t, sbp->sb_blocklog, mp->m_allocsize_log);
     mp->m_allocsize_blocks = 1U << (mp->m_allocsize_log - sbp->sb_blocklog);
 
     /* set the low space thresholds for dynamic preallocation */
     xfs_set_low_space_thresholds(mp);
 
     /*
      * If enabled, sparse inode chunk alignment is expected to match the
      * cluster size. Full inode chunk alignment must match the chunk size,
      * but that is checked on sb read verification...
      */
     if (xfs_has_sparseinodes(mp) &&
         mp->m_sb.sb_spino_align !=
             XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw)) {
         xfs_warn(mp,
     "Sparse inode block alignment (%u) must match cluster size (%llu).",
              mp->m_sb.sb_spino_align,
              XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw));
         error = -EINVAL;
         goto out_remove_uuid;
     }
 
     /*
      * Check that the data (and log if separate) is an ok size.
      */
     error = xfs_check_sizes(mp);
     if (error)
         goto out_remove_uuid;
 
     /*
      * Initialize realtime fields in the mount structure
      */
     error = xfs_rtmount_init(mp);
     if (error) {
         xfs_warn(mp, "RT mount failed");
         goto out_remove_uuid;
     }
 
     /*
      *  Copies the low order bits of the timestamp and the randomly
      *  set "sequence" number out of a UUID.
      */
     mp->m_fixedfsid[0] =
         (get_unaligned_be16(&sbp->sb_uuid.b[8]) << 16) |
          get_unaligned_be16(&sbp->sb_uuid.b[4]);
     mp->m_fixedfsid[1] = get_unaligned_be32(&sbp->sb_uuid.b[0]);
 
     error = xfs_da_mount(mp);
     if (error) {
         xfs_warn(mp, "Failed dir/attr init: %d", error);
         goto out_remove_uuid;
     }
 
     /*
      * Initialize the precomputed transaction reservations values.
      */
     xfs_trans_init(mp);
 
     /*
      * Allocate and initialize the per-ag data.
      */
     error = xfs_initialize_perag(mp, sbp->sb_agcount, mp->m_sb.sb_dblocks,
             &mp->m_maxagi);
     if (error) {
         xfs_warn(mp, "Failed per-ag init: %d", error);
         goto out_free_dir;
     }
 
     if (XFS_IS_CORRUPT(mp, !sbp->sb_logblocks)) {
         xfs_warn(mp, "no log defined");
         error = -EFSCORRUPTED;
         goto out_free_perag;
     }
 
     error = xfs_inodegc_register_shrinker(mp);
     if (error)
         goto out_fail_wait;
 
     /*
      * Log's mount-time initialization. The first part of recovery can place
      * some items on the AIL, to be handled when recovery is finished or
      * cancelled.
      */
     error = xfs_log_mount(mp, mp->m_logdev_targp,
                   XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
                   XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
     if (error) {
         xfs_warn(mp, "log mount failed");
         goto out_inodegc_shrinker;
     }
 
     /* Enable background inode inactivation workers. */
     xfs_inodegc_start(mp);
     xfs_blockgc_start(mp);
 
     /*
      * Now that we've recovered any pending superblock feature bit
      * additions, we can finish setting up the attr2 behaviour for the
      * mount. The noattr2 option overrides the superblock flag, so only
      * check the superblock feature flag if the mount option is not set.
      */
     if (xfs_has_noattr2(mp)) {
         mp->m_features &= ~XFS_FEAT_ATTR2;
     } else if (!xfs_has_attr2(mp) &&
            (mp->m_sb.sb_features2 & XFS_SB_VERSION2_ATTR2BIT)) {
         mp->m_features |= XFS_FEAT_ATTR2;
     }
 
     /*
      * Get and sanity-check the root inode.
      * Save the pointer to it in the mount structure.
      */
     error = xfs_iget(mp, NULL, sbp->sb_rootino, XFS_IGET_UNTRUSTED,
              XFS_ILOCK_EXCL, &rip);
     if (error) {
         xfs_warn(mp,
             "Failed to read root inode 0x%llx, error %d",
             sbp->sb_rootino, -error);
         goto out_log_dealloc;
     }
 
     ASSERT(rip != NULL);
 
     if (XFS_IS_CORRUPT(mp, !S_ISDIR(VFS_I(rip)->i_mode))) {
         xfs_warn(mp, "corrupted root inode %llu: not a directory",
             (unsigned long long)rip->i_ino);
         xfs_iunlock(rip, XFS_ILOCK_EXCL);
         error = -EFSCORRUPTED;
         goto out_rele_rip;
     }
     mp->m_rootip = rip; /* save it */
 
     xfs_iunlock(rip, XFS_ILOCK_EXCL);
 
     /*
      * Initialize realtime inode pointers in the mount structure
      */
     error = xfs_rtmount_inodes(mp);
     if (error) {
         /*
          * Free up the root inode.
          */
         xfs_warn(mp, "failed to read RT inodes");
         goto out_rele_rip;
     }
 
     /* Make sure the summary counts are ok. */
     error = xfs_check_summary_counts(mp);
     if (error)
         goto out_rtunmount;
 
     /*
      * If this is a read-only mount defer the superblock updates until
      * the next remount into writeable mode.  Otherwise we would never
      * perform the update e.g. for the root filesystem.
      */
     if (mp->m_update_sb && !xfs_is_readonly(mp)) {
         error = xfs_sync_sb(mp, false);
         if (error) {
             xfs_warn(mp, "failed to write sb changes");
             goto out_rtunmount;
         }
     }
 
     /*
      * Initialise the XFS quota management subsystem for this mount
      */
     if (XFS_IS_QUOTA_ON(mp)) {
         error = xfs_qm_newmount(mp, &quotamount, &quotaflags);
         if (error)
             goto out_rtunmount;
     } else {
         /*
          * If a file system had quotas running earlier, but decided to
          * mount without -o uquota/pquota/gquota options, revoke the
          * quotachecked license.
          */
         if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
             xfs_notice(mp, "resetting quota flags");
             error = xfs_mount_reset_sbqflags(mp);
             if (error)
                 goto out_rtunmount;
         }
     }
 
     /*
      * Finish recovering the file system.  This part needed to be delayed
      * until after the root and real-time bitmap inodes were consistently
      * read in.  Temporarily create per-AG space reservations for metadata
      * btree shape changes because space freeing transactions (for inode
      * inactivation) require the per-AG reservation in lieu of reserving
      * blocks.
      */
     error = xfs_fs_reserve_ag_blocks(mp);
     if (error && error == -ENOSPC)
         xfs_warn(mp,
     "ENOSPC reserving per-AG metadata pool, log recovery may fail.");
     error = xfs_log_mount_finish(mp);
     xfs_fs_unreserve_ag_blocks(mp);
     if (error) {
         xfs_warn(mp, "log mount finish failed");
         goto out_rtunmount;
     }
 
     /*
      * Now the log is fully replayed, we can transition to full read-only
      * mode for read-only mounts. This will sync all the metadata and clean
      * the log so that the recovery we just performed does not have to be
      * replayed again on the next mount.
      *
      * We use the same quiesce mechanism as the rw->ro remount, as they are
      * semantically identical operations.
      */
     if (xfs_is_readonly(mp) && !xfs_has_norecovery(mp))
         xfs_log_clean(mp);
 
     /*
      * Complete the quota initialisation, post-log-replay component.
      */
     if (quotamount) {
         ASSERT(mp->m_qflags == 0);
         mp->m_qflags = quotaflags;
 
         xfs_qm_mount_quotas(mp);
     }
 
     /*
      * Now we are mounted, reserve a small amount of unused space for
      * privileged transactions. This is needed so that transaction
      * space required for critical operations can dip into this pool
      * when at ENOSPC. This is needed for operations like create with
      * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
      * are not allowed to use this reserved space.
      *
      * This may drive us straight to ENOSPC on mount, but that implies
      * we were already there on the last unmount. Warn if this occurs.
      */
     if (!xfs_is_readonly(mp)) {
         resblks = xfs_default_resblks(mp);
         error = xfs_reserve_blocks(mp, &resblks, NULL);
         if (error)
             xfs_warn(mp,
     "Unable to allocate reserve blocks. Continuing without reserve pool.");
 
         /* Reserve AG blocks for future btree expansion. */
         error = xfs_fs_reserve_ag_blocks(mp);
         if (error && error != -ENOSPC)
             goto out_agresv;
     }
 
     return 0;
 
  out_agresv:
     xfs_fs_unreserve_ag_blocks(mp);
     xfs_qm_unmount_quotas(mp);
  out_rtunmount:
     xfs_rtunmount_inodes(mp);
  out_rele_rip:
     xfs_irele(rip);
     /* Clean out dquots that might be in memory after quotacheck. */
     xfs_qm_unmount(mp);
 
     /*
      * Inactivate all inodes that might still be in memory after a log
      * intent recovery failure so that reclaim can free them.  Metadata
      * inodes and the root directory shouldn't need inactivation, but the
      * mount failed for some reason, so pull down all the state and flee.
      */
     xfs_inodegc_flush(mp);
 
     /*
      * Flush all inode reclamation work and flush the log.
      * We have to do this /after/ rtunmount and qm_unmount because those
      * two will have scheduled delayed reclaim for the rt/quota inodes.
      *
      * This is slightly different from the unmountfs call sequence
      * because we could be tearing down a partially set up mount.  In
      * particular, if log_mount_finish fails we bail out without calling
      * qm_unmount_quotas and therefore rely on qm_unmount to release the
      * quota inodes.
      */
     xfs_unmount_flush_inodes(mp);
  out_log_dealloc:
     xfs_log_mount_cancel(mp);
  out_inodegc_shrinker:
     unregister_shrinker(&mp->m_inodegc_shrinker);
  out_fail_wait:
     if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
         xfs_buftarg_drain(mp->m_logdev_targp);
     xfs_buftarg_drain(mp->m_ddev_targp);
  out_free_perag:
     xfs_free_perag(mp);
  out_free_dir:
     xfs_da_unmount(mp);
  out_remove_uuid:
     xfs_uuid_unmount(mp);
  out_remove_errortag:
     xfs_errortag_del(mp);
  out_remove_error_sysfs:
     xfs_error_sysfs_del(mp);
  out_del_stats:
     xfs_sysfs_del(&mp->m_stats.xs_kobj);
  out_remove_sysfs:
     xfs_sysfs_del(&mp->m_kobj);
  out:
     return error;
 }
 
 /*
  * This flushes out the inodes,dquots and the superblock, unmounts the
  * log and makes sure that incore structures are freed.
  */
 void
 xfs_unmountfs(
     struct xfs_mount    *mp)
 {
     uint64_t        resblks;
     int         error;
 
     /*
      * Perform all on-disk metadata updates required to inactivate inodes
      * that the VFS evicted earlier in the unmount process.  Freeing inodes
      * and discarding CoW fork preallocations can cause shape changes to
      * the free inode and refcount btrees, respectively, so we must finish
      * this before we discard the metadata space reservations.  Metadata
      * inodes and the root directory do not require inactivation.
      */
     xfs_inodegc_flush(mp);
 
     xfs_blockgc_stop(mp);
     xfs_fs_unreserve_ag_blocks(mp);
     xfs_qm_unmount_quotas(mp);
     xfs_rtunmount_inodes(mp);
     xfs_irele(mp->m_rootip);
 
     xfs_unmount_flush_inodes(mp);
 
     xfs_qm_unmount(mp);
 
     /*
      * Unreserve any blocks we have so that when we unmount we don't account
      * the reserved free space as used. This is really only necessary for
      * lazy superblock counting because it trusts the incore superblock
      * counters to be absolutely correct on clean unmount.
      *
      * We don't bother correcting this elsewhere for lazy superblock
      * counting because on mount of an unclean filesystem we reconstruct the
      * correct counter value and this is irrelevant.
      *
      * For non-lazy counter filesystems, this doesn't matter at all because
      * we only every apply deltas to the superblock and hence the incore
      * value does not matter....
      */
     resblks = 0;
     error = xfs_reserve_blocks(mp, &resblks, NULL);
     if (error)
         xfs_warn(mp, "Unable to free reserved block pool. "
                 "Freespace may not be correct on next mount.");
 
     xfs_log_unmount(mp);
     xfs_da_unmount(mp);
     xfs_uuid_unmount(mp);
 
 #if defined(DEBUG)
     xfs_errortag_clearall(mp);
 #endif
     unregister_shrinker(&mp->m_inodegc_shrinker);
     xfs_free_perag(mp);
 
     xfs_errortag_del(mp);
     xfs_error_sysfs_del(mp);
     xfs_sysfs_del(&mp->m_stats.xs_kobj);
     xfs_sysfs_del(&mp->m_kobj);
 }
 
 /*
  * Determine whether modifications can proceed. The caller specifies the minimum
  * freeze level for which modifications should not be allowed. This allows
  * certain operations to proceed while the freeze sequence is in progress, if
  * necessary.
  */
 bool
 xfs_fs_writable(
     struct xfs_mount    *mp,
     int         level)
 {
     ASSERT(level > SB_UNFROZEN);
     if ((mp->m_super->s_writers.frozen >= level) ||
         xfs_is_shutdown(mp) || xfs_is_readonly(mp))
         return false;
 
     return true;
 }
 
 /* Adjust m_fdblocks or m_frextents. */
 int
 xfs_mod_freecounter(
     struct xfs_mount    *mp,
     struct percpu_counter   *counter,
     int64_t         delta,
     bool            rsvd)
 {
     int64_t         lcounter;
     long long       res_used;
     uint64_t        set_aside = 0;
     s32         batch;
     bool            has_resv_pool;
 
     ASSERT(counter == &mp->m_fdblocks || counter == &mp->m_frextents);
     has_resv_pool = (counter == &mp->m_fdblocks);
     if (rsvd)
         ASSERT(has_resv_pool);
 
     if (delta > 0) {
         /*
          * If the reserve pool is depleted, put blocks back into it
          * first. Most of the time the pool is full.
          */
         if (likely(!has_resv_pool ||
                mp->m_resblks == mp->m_resblks_avail)) {
             percpu_counter_add(counter, delta);
             return 0;
         }
 
         spin_lock(&mp->m_sb_lock);
         res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
 
         if (res_used > delta) {
             mp->m_resblks_avail += delta;
         } else {
             delta -= res_used;
             mp->m_resblks_avail = mp->m_resblks;
             percpu_counter_add(counter, delta);
         }
         spin_unlock(&mp->m_sb_lock);
         return 0;
     }
 
     /*
      * Taking blocks away, need to be more accurate the closer we
      * are to zero.
      *
      * If the counter has a value of less than 2 * max batch size,
      * then make everything serialise as we are real close to
      * ENOSPC.
      */
     if (__percpu_counter_compare(counter, 2 * XFS_FDBLOCKS_BATCH,
                      XFS_FDBLOCKS_BATCH) < 0)
         batch = 1;
     else
         batch = XFS_FDBLOCKS_BATCH;
 
     /*
      * Set aside allocbt blocks because these blocks are tracked as free
      * space but not available for allocation. Technically this means that a
      * single reservation cannot consume all remaining free space, but the
      * ratio of allocbt blocks to usable free blocks should be rather small.
      * The tradeoff without this is that filesystems that maintain high
      * perag block reservations can over reserve physical block availability
      * and fail physical allocation, which leads to much more serious
      * problems (i.e. transaction abort, pagecache discards, etc.) than
      * slightly premature -ENOSPC.
      */
     if (has_resv_pool)
         set_aside = xfs_fdblocks_unavailable(mp);
     percpu_counter_add_batch(counter, delta, batch);
     if (__percpu_counter_compare(counter, set_aside,
                      XFS_FDBLOCKS_BATCH) >= 0) {
         /* we had space! */
         return 0;
     }
 
     /*
      * lock up the sb for dipping into reserves before releasing the space
      * that took us to ENOSPC.
      */
     spin_lock(&mp->m_sb_lock);
     percpu_counter_add(counter, -delta);
     if (!has_resv_pool || !rsvd)
         goto fdblocks_enospc;
 
     lcounter = (long long)mp->m_resblks_avail + delta;
     if (lcounter >= 0) {
         mp->m_resblks_avail = lcounter;
         spin_unlock(&mp->m_sb_lock);
         return 0;
     }
     xfs_warn_once(mp,
 "Reserve blocks depleted! Consider increasing reserve pool size.");
 
 fdblocks_enospc:
     spin_unlock(&mp->m_sb_lock);
     return -ENOSPC;
 }
 
 /*
  * Used to free the superblock along various error paths.
  */
 void
 xfs_freesb(
     struct xfs_mount    *mp)
 {
     struct xfs_buf      *bp = mp->m_sb_bp;
 
     xfs_buf_lock(bp);
     mp->m_sb_bp = NULL;
     xfs_buf_relse(bp);
 }
 
 /*
  * If the underlying (data/log/rt) device is readonly, there are some
  * operations that cannot proceed.
  */
 int
 xfs_dev_is_read_only(
     struct xfs_mount    *mp,
     char            *message)
 {
     if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
         xfs_readonly_buftarg(mp->m_logdev_targp) ||
         (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
         xfs_notice(mp, "%s required on read-only device.", message);
         xfs_notice(mp, "write access unavailable, cannot proceed.");
         return -EROFS;
     }
     return 0;
 }
 
 /* Force the summary counters to be recalculated at next mount. */
 void
 xfs_force_summary_recalc(
     struct xfs_mount    *mp)
 {
     if (!xfs_has_lazysbcount(mp))
         return;
 
     xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
 }
 
 /*
  * Enable a log incompat feature flag in the primary superblock.  The caller
  * cannot have any other transactions in progress.
  */
 int
 xfs_add_incompat_log_feature(
     struct xfs_mount    *mp,
     uint32_t        feature)
 {
     struct xfs_dsb      *dsb;
     int         error;
 
     ASSERT(hweight32(feature) == 1);
     ASSERT(!(feature & XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
 
     /*
      * Force the log to disk and kick the background AIL thread to reduce
      * the chances that the bwrite will stall waiting for the AIL to unpin
      * the primary superblock buffer.  This isn't a data integrity
      * operation, so we don't need a synchronous push.
      */
     error = xfs_log_force(mp, XFS_LOG_SYNC);
     if (error)
         return error;
     xfs_ail_push_all(mp->m_ail);
 
     /*
      * Lock the primary superblock buffer to serialize all callers that
      * are trying to set feature bits.
      */
     xfs_buf_lock(mp->m_sb_bp);
     xfs_buf_hold(mp->m_sb_bp);
 
     if (xfs_is_shutdown(mp)) {
         error = -EIO;
         goto rele;
     }
 
     if (xfs_sb_has_incompat_log_feature(&mp->m_sb, feature))
         goto rele;
 
     /*
      * Write the primary superblock to disk immediately, because we need
      * the log_incompat bit to be set in the primary super now to protect
      * the log items that we're going to commit later.
      */
     dsb = mp->m_sb_bp->b_addr;
     xfs_sb_to_disk(dsb, &mp->m_sb);
     dsb->sb_features_log_incompat |= cpu_to_be32(feature);
     error = xfs_bwrite(mp->m_sb_bp);
     if (error)
         goto shutdown;
 
     /*
      * Add the feature bits to the incore superblock before we unlock the
      * buffer.
      */
     xfs_sb_add_incompat_log_features(&mp->m_sb, feature);
     xfs_buf_relse(mp->m_sb_bp);
 
     /* Log the superblock to disk. */
     return xfs_sync_sb(mp, false);
 shutdown:
     xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
 rele:
     xfs_buf_relse(mp->m_sb_bp);
     return error;
 }
 
 /*
  * Clear all the log incompat flags from the superblock.
  *
  * The caller cannot be in a transaction, must ensure that the log does not
  * contain any log items protected by any log incompat bit, and must ensure
  * that there are no other threads that depend on the state of the log incompat
  * feature flags in the primary super.
  *
  * Returns true if the superblock is dirty.
  */
 bool
 xfs_clear_incompat_log_features(
     struct xfs_mount    *mp)
 {
     bool            ret = false;
 
     if (!xfs_has_crc(mp) ||
         !xfs_sb_has_incompat_log_feature(&mp->m_sb,
                 XFS_SB_FEAT_INCOMPAT_LOG_ALL) ||
         xfs_is_shutdown(mp))
         return false;
 
     /*
      * Update the incore superblock.  We synchronize on the primary super
      * buffer lock to be consistent with the add function, though at least
      * in theory this shouldn't be necessary.
      */
     xfs_buf_lock(mp->m_sb_bp);
     xfs_buf_hold(mp->m_sb_bp);
 
     if (xfs_sb_has_incompat_log_feature(&mp->m_sb,
                 XFS_SB_FEAT_INCOMPAT_LOG_ALL)) {
         xfs_sb_remove_incompat_log_features(&mp->m_sb);
         ret = true;
     }
 
     xfs_buf_relse(mp->m_sb_bp);
     return ret;
 }
 
 /*
  * Update the in-core delayed block counter.
  *
  * We prefer to update the counter without having to take a spinlock for every
  * counter update (i.e. batching).  Each change to delayed allocation
  * reservations can change can easily exceed the default percpu counter
  * batching, so we use a larger batch factor here.
  *
  * Note that we don't currently have any callers requiring fast summation
  * (e.g. percpu_counter_read) so we can use a big batch value here.
  */
 #define XFS_DELALLOC_BATCH  (4096)
 void
 xfs_mod_delalloc(
     struct xfs_mount    *mp,
     int64_t         delta)
 {
     percpu_counter_add_batch(&mp->m_delalloc_blks, delta,
             XFS_DELALLOC_BATCH);
 }

This page was automatically generated by the 2.1.0 LXR engine. The LXR team