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-rw-r--r--fs/xfs/xfs_fsops.c616
1 files changed, 616 insertions, 0 deletions
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
new file mode 100644
index 0000000000..7cb75cb6b8
--- /dev/null
+++ b/fs/xfs/xfs_fsops.c
@@ -0,0 +1,616 @@
+// 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_sb.h"
+#include "xfs_mount.h"
+#include "xfs_trans.h"
+#include "xfs_error.h"
+#include "xfs_alloc.h"
+#include "xfs_fsops.h"
+#include "xfs_trans_space.h"
+#include "xfs_log.h"
+#include "xfs_log_priv.h"
+#include "xfs_ag.h"
+#include "xfs_ag_resv.h"
+#include "xfs_trace.h"
+
+/*
+ * Write new AG headers to disk. Non-transactional, but need to be
+ * written and completed prior to the growfs transaction being logged.
+ * To do this, we use a delayed write buffer list and wait for
+ * submission and IO completion of the list as a whole. This allows the
+ * IO subsystem to merge all the AG headers in a single AG into a single
+ * IO and hide most of the latency of the IO from us.
+ *
+ * This also means that if we get an error whilst building the buffer
+ * list to write, we can cancel the entire list without having written
+ * anything.
+ */
+static int
+xfs_resizefs_init_new_ags(
+ struct xfs_trans *tp,
+ struct aghdr_init_data *id,
+ xfs_agnumber_t oagcount,
+ xfs_agnumber_t nagcount,
+ xfs_rfsblock_t delta,
+ struct xfs_perag *last_pag,
+ bool *lastag_extended)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ xfs_rfsblock_t nb = mp->m_sb.sb_dblocks + delta;
+ int error;
+
+ *lastag_extended = false;
+
+ INIT_LIST_HEAD(&id->buffer_list);
+ for (id->agno = nagcount - 1;
+ id->agno >= oagcount;
+ id->agno--, delta -= id->agsize) {
+
+ if (id->agno == nagcount - 1)
+ id->agsize = nb - (id->agno *
+ (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
+ else
+ id->agsize = mp->m_sb.sb_agblocks;
+
+ error = xfs_ag_init_headers(mp, id);
+ if (error) {
+ xfs_buf_delwri_cancel(&id->buffer_list);
+ return error;
+ }
+ }
+
+ error = xfs_buf_delwri_submit(&id->buffer_list);
+ if (error)
+ return error;
+
+ if (delta) {
+ *lastag_extended = true;
+ error = xfs_ag_extend_space(last_pag, tp, delta);
+ }
+ return error;
+}
+
+/*
+ * growfs operations
+ */
+static int
+xfs_growfs_data_private(
+ struct xfs_mount *mp, /* mount point for filesystem */
+ struct xfs_growfs_data *in) /* growfs data input struct */
+{
+ struct xfs_buf *bp;
+ int error;
+ xfs_agnumber_t nagcount;
+ xfs_agnumber_t nagimax = 0;
+ xfs_rfsblock_t nb, nb_div, nb_mod;
+ int64_t delta;
+ bool lastag_extended = false;
+ xfs_agnumber_t oagcount;
+ struct xfs_trans *tp;
+ struct aghdr_init_data id = {};
+ struct xfs_perag *last_pag;
+
+ nb = in->newblocks;
+ error = xfs_sb_validate_fsb_count(&mp->m_sb, nb);
+ if (error)
+ return error;
+
+ if (nb > mp->m_sb.sb_dblocks) {
+ error = xfs_buf_read_uncached(mp->m_ddev_targp,
+ XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
+ XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
+ if (error)
+ return error;
+ xfs_buf_relse(bp);
+ }
+
+ nb_div = nb;
+ nb_mod = do_div(nb_div, mp->m_sb.sb_agblocks);
+ if (nb_mod && nb_mod >= XFS_MIN_AG_BLOCKS)
+ nb_div++;
+ else if (nb_mod)
+ nb = nb_div * mp->m_sb.sb_agblocks;
+
+ if (nb_div > XFS_MAX_AGNUMBER + 1) {
+ nb_div = XFS_MAX_AGNUMBER + 1;
+ nb = nb_div * mp->m_sb.sb_agblocks;
+ }
+ nagcount = nb_div;
+ delta = nb - mp->m_sb.sb_dblocks;
+ /*
+ * Reject filesystems with a single AG because they are not
+ * supported, and reject a shrink operation that would cause a
+ * filesystem to become unsupported.
+ */
+ if (delta < 0 && nagcount < 2)
+ return -EINVAL;
+
+ oagcount = mp->m_sb.sb_agcount;
+ /* allocate the new per-ag structures */
+ if (nagcount > oagcount) {
+ error = xfs_initialize_perag(mp, nagcount, nb, &nagimax);
+ if (error)
+ return error;
+ } else if (nagcount < oagcount) {
+ /* TODO: shrinking the entire AGs hasn't yet completed */
+ return -EINVAL;
+ }
+
+ if (delta > 0)
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,
+ XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
+ &tp);
+ else
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata, -delta, 0,
+ 0, &tp);
+ if (error)
+ return error;
+
+ last_pag = xfs_perag_get(mp, oagcount - 1);
+ if (delta > 0) {
+ error = xfs_resizefs_init_new_ags(tp, &id, oagcount, nagcount,
+ delta, last_pag, &lastag_extended);
+ } else {
+ xfs_warn_mount(mp, XFS_OPSTATE_WARNED_SHRINK,
+ "EXPERIMENTAL online shrink feature in use. Use at your own risk!");
+
+ error = xfs_ag_shrink_space(last_pag, &tp, -delta);
+ }
+ xfs_perag_put(last_pag);
+ if (error)
+ goto out_trans_cancel;
+
+ /*
+ * Update changed superblock fields transactionally. These are not
+ * seen by the rest of the world until the transaction commit applies
+ * them atomically to the superblock.
+ */
+ if (nagcount > oagcount)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
+ if (delta)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS, delta);
+ if (id.nfree)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, id.nfree);
+
+ /*
+ * Sync sb counters now to reflect the updated values. This is
+ * particularly important for shrink because the write verifier
+ * will fail if sb_fdblocks is ever larger than sb_dblocks.
+ */
+ if (xfs_has_lazysbcount(mp))
+ xfs_log_sb(tp);
+
+ xfs_trans_set_sync(tp);
+ error = xfs_trans_commit(tp);
+ if (error)
+ return error;
+
+ /* New allocation groups fully initialized, so update mount struct */
+ if (nagimax)
+ mp->m_maxagi = nagimax;
+ xfs_set_low_space_thresholds(mp);
+ mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
+
+ if (delta > 0) {
+ /*
+ * If we expanded the last AG, free the per-AG reservation
+ * so we can reinitialize it with the new size.
+ */
+ if (lastag_extended) {
+ struct xfs_perag *pag;
+
+ pag = xfs_perag_get(mp, id.agno);
+ error = xfs_ag_resv_free(pag);
+ xfs_perag_put(pag);
+ if (error)
+ return error;
+ }
+ /*
+ * Reserve AG metadata blocks. ENOSPC here does not mean there
+ * was a growfs failure, just that there still isn't space for
+ * new user data after the grow has been run.
+ */
+ error = xfs_fs_reserve_ag_blocks(mp);
+ if (error == -ENOSPC)
+ error = 0;
+ }
+ return error;
+
+out_trans_cancel:
+ xfs_trans_cancel(tp);
+ return error;
+}
+
+static int
+xfs_growfs_log_private(
+ struct xfs_mount *mp, /* mount point for filesystem */
+ struct xfs_growfs_log *in) /* growfs log input struct */
+{
+ xfs_extlen_t nb;
+
+ nb = in->newblocks;
+ if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
+ return -EINVAL;
+ if (nb == mp->m_sb.sb_logblocks &&
+ in->isint == (mp->m_sb.sb_logstart != 0))
+ return -EINVAL;
+ /*
+ * Moving the log is hard, need new interfaces to sync
+ * the log first, hold off all activity while moving it.
+ * Can have shorter or longer log in the same space,
+ * or transform internal to external log or vice versa.
+ */
+ return -ENOSYS;
+}
+
+static int
+xfs_growfs_imaxpct(
+ struct xfs_mount *mp,
+ __u32 imaxpct)
+{
+ struct xfs_trans *tp;
+ int dpct;
+ int error;
+
+ if (imaxpct > 100)
+ return -EINVAL;
+
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,
+ XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp);
+ if (error)
+ return error;
+
+ dpct = imaxpct - mp->m_sb.sb_imax_pct;
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
+ xfs_trans_set_sync(tp);
+ return xfs_trans_commit(tp);
+}
+
+/*
+ * protected versions of growfs function acquire and release locks on the mount
+ * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
+ * XFS_IOC_FSGROWFSRT
+ */
+int
+xfs_growfs_data(
+ struct xfs_mount *mp,
+ struct xfs_growfs_data *in)
+{
+ int error = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!mutex_trylock(&mp->m_growlock))
+ return -EWOULDBLOCK;
+
+ /* update imaxpct separately to the physical grow of the filesystem */
+ if (in->imaxpct != mp->m_sb.sb_imax_pct) {
+ error = xfs_growfs_imaxpct(mp, in->imaxpct);
+ if (error)
+ goto out_error;
+ }
+
+ if (in->newblocks != mp->m_sb.sb_dblocks) {
+ error = xfs_growfs_data_private(mp, in);
+ if (error)
+ goto out_error;
+ }
+
+ /* Post growfs calculations needed to reflect new state in operations */
+ if (mp->m_sb.sb_imax_pct) {
+ uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
+ do_div(icount, 100);
+ M_IGEO(mp)->maxicount = XFS_FSB_TO_INO(mp, icount);
+ } else
+ M_IGEO(mp)->maxicount = 0;
+
+ /* Update secondary superblocks now the physical grow has completed */
+ error = xfs_update_secondary_sbs(mp);
+
+out_error:
+ /*
+ * Increment the generation unconditionally, the error could be from
+ * updating the secondary superblocks, in which case the new size
+ * is live already.
+ */
+ mp->m_generation++;
+ mutex_unlock(&mp->m_growlock);
+ return error;
+}
+
+int
+xfs_growfs_log(
+ xfs_mount_t *mp,
+ struct xfs_growfs_log *in)
+{
+ int error;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!mutex_trylock(&mp->m_growlock))
+ return -EWOULDBLOCK;
+ error = xfs_growfs_log_private(mp, in);
+ mutex_unlock(&mp->m_growlock);
+ return error;
+}
+
+/*
+ * exported through ioctl XFS_IOC_FSCOUNTS
+ */
+
+void
+xfs_fs_counts(
+ xfs_mount_t *mp,
+ xfs_fsop_counts_t *cnt)
+{
+ cnt->allocino = percpu_counter_read_positive(&mp->m_icount);
+ cnt->freeino = percpu_counter_read_positive(&mp->m_ifree);
+ cnt->freedata = percpu_counter_read_positive(&mp->m_fdblocks) -
+ xfs_fdblocks_unavailable(mp);
+ cnt->freertx = percpu_counter_read_positive(&mp->m_frextents);
+}
+
+/*
+ * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
+ *
+ * xfs_reserve_blocks is called to set m_resblks
+ * in the in-core mount table. The number of unused reserved blocks
+ * is kept in m_resblks_avail.
+ *
+ * Reserve the requested number of blocks if available. Otherwise return
+ * as many as possible to satisfy the request. The actual number
+ * reserved are returned in outval
+ *
+ * A null inval pointer indicates that only the current reserved blocks
+ * available should be returned no settings are changed.
+ */
+
+int
+xfs_reserve_blocks(
+ xfs_mount_t *mp,
+ uint64_t *inval,
+ xfs_fsop_resblks_t *outval)
+{
+ int64_t lcounter, delta;
+ int64_t fdblks_delta = 0;
+ uint64_t request;
+ int64_t free;
+ int error = 0;
+
+ /* If inval is null, report current values and return */
+ if (inval == (uint64_t *)NULL) {
+ if (!outval)
+ return -EINVAL;
+ outval->resblks = mp->m_resblks;
+ outval->resblks_avail = mp->m_resblks_avail;
+ return 0;
+ }
+
+ request = *inval;
+
+ /*
+ * With per-cpu counters, this becomes an interesting problem. we need
+ * to work out if we are freeing or allocation blocks first, then we can
+ * do the modification as necessary.
+ *
+ * We do this under the m_sb_lock so that if we are near ENOSPC, we will
+ * hold out any changes while we work out what to do. This means that
+ * the amount of free space can change while we do this, so we need to
+ * retry if we end up trying to reserve more space than is available.
+ */
+ spin_lock(&mp->m_sb_lock);
+
+ /*
+ * If our previous reservation was larger than the current value,
+ * then move any unused blocks back to the free pool. Modify the resblks
+ * counters directly since we shouldn't have any problems unreserving
+ * space.
+ */
+ if (mp->m_resblks > request) {
+ lcounter = mp->m_resblks_avail - request;
+ if (lcounter > 0) { /* release unused blocks */
+ fdblks_delta = lcounter;
+ mp->m_resblks_avail -= lcounter;
+ }
+ mp->m_resblks = request;
+ if (fdblks_delta) {
+ spin_unlock(&mp->m_sb_lock);
+ error = xfs_mod_fdblocks(mp, fdblks_delta, 0);
+ spin_lock(&mp->m_sb_lock);
+ }
+
+ goto out;
+ }
+
+ /*
+ * If the request is larger than the current reservation, reserve the
+ * blocks before we update the reserve counters. Sample m_fdblocks and
+ * perform a partial reservation if the request exceeds free space.
+ *
+ * The code below estimates how many blocks it can request from
+ * fdblocks to stash in the reserve pool. This is a classic TOCTOU
+ * race since fdblocks updates are not always coordinated via
+ * m_sb_lock. Set the reserve size even if there's not enough free
+ * space to fill it because mod_fdblocks will refill an undersized
+ * reserve when it can.
+ */
+ free = percpu_counter_sum(&mp->m_fdblocks) -
+ xfs_fdblocks_unavailable(mp);
+ delta = request - mp->m_resblks;
+ mp->m_resblks = request;
+ if (delta > 0 && free > 0) {
+ /*
+ * We'll either succeed in getting space from the free block
+ * count or we'll get an ENOSPC. Don't set the reserved flag
+ * here - we don't want to reserve the extra reserve blocks
+ * from the reserve.
+ *
+ * The desired reserve size can change after we drop the lock.
+ * Use mod_fdblocks to put the space into the reserve or into
+ * fdblocks as appropriate.
+ */
+ fdblks_delta = min(free, delta);
+ spin_unlock(&mp->m_sb_lock);
+ error = xfs_mod_fdblocks(mp, -fdblks_delta, 0);
+ if (!error)
+ xfs_mod_fdblocks(mp, fdblks_delta, 0);
+ spin_lock(&mp->m_sb_lock);
+ }
+out:
+ if (outval) {
+ outval->resblks = mp->m_resblks;
+ outval->resblks_avail = mp->m_resblks_avail;
+ }
+
+ spin_unlock(&mp->m_sb_lock);
+ return error;
+}
+
+int
+xfs_fs_goingdown(
+ xfs_mount_t *mp,
+ uint32_t inflags)
+{
+ switch (inflags) {
+ case XFS_FSOP_GOING_FLAGS_DEFAULT: {
+ if (!freeze_bdev(mp->m_super->s_bdev)) {
+ xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
+ thaw_bdev(mp->m_super->s_bdev);
+ }
+ break;
+ }
+ case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
+ xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
+ break;
+ case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
+ xfs_force_shutdown(mp,
+ SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Force a shutdown of the filesystem instantly while keeping the filesystem
+ * consistent. We don't do an unmount here; just shutdown the shop, make sure
+ * that absolutely nothing persistent happens to this filesystem after this
+ * point.
+ *
+ * The shutdown state change is atomic, resulting in the first and only the
+ * first shutdown call processing the shutdown. This means we only shutdown the
+ * log once as it requires, and we don't spam the logs when multiple concurrent
+ * shutdowns race to set the shutdown flags.
+ */
+void
+xfs_do_force_shutdown(
+ struct xfs_mount *mp,
+ uint32_t flags,
+ char *fname,
+ int lnnum)
+{
+ int tag;
+ const char *why;
+
+
+ if (test_and_set_bit(XFS_OPSTATE_SHUTDOWN, &mp->m_opstate)) {
+ xlog_shutdown_wait(mp->m_log);
+ return;
+ }
+ if (mp->m_sb_bp)
+ mp->m_sb_bp->b_flags |= XBF_DONE;
+
+ if (flags & SHUTDOWN_FORCE_UMOUNT)
+ xfs_alert(mp, "User initiated shutdown received.");
+
+ if (xlog_force_shutdown(mp->m_log, flags)) {
+ tag = XFS_PTAG_SHUTDOWN_LOGERROR;
+ why = "Log I/O Error";
+ } else if (flags & SHUTDOWN_CORRUPT_INCORE) {
+ tag = XFS_PTAG_SHUTDOWN_CORRUPT;
+ why = "Corruption of in-memory data";
+ } else if (flags & SHUTDOWN_CORRUPT_ONDISK) {
+ tag = XFS_PTAG_SHUTDOWN_CORRUPT;
+ why = "Corruption of on-disk metadata";
+ } else if (flags & SHUTDOWN_DEVICE_REMOVED) {
+ tag = XFS_PTAG_SHUTDOWN_IOERROR;
+ why = "Block device removal";
+ } else {
+ tag = XFS_PTAG_SHUTDOWN_IOERROR;
+ why = "Metadata I/O Error";
+ }
+
+ trace_xfs_force_shutdown(mp, tag, flags, fname, lnnum);
+
+ xfs_alert_tag(mp, tag,
+"%s (0x%x) detected at %pS (%s:%d). Shutting down filesystem.",
+ why, flags, __return_address, fname, lnnum);
+ xfs_alert(mp,
+ "Please unmount the filesystem and rectify the problem(s)");
+ if (xfs_error_level >= XFS_ERRLEVEL_HIGH)
+ xfs_stack_trace();
+}
+
+/*
+ * Reserve free space for per-AG metadata.
+ */
+int
+xfs_fs_reserve_ag_blocks(
+ struct xfs_mount *mp)
+{
+ xfs_agnumber_t agno;
+ struct xfs_perag *pag;
+ int error = 0;
+ int err2;
+
+ mp->m_finobt_nores = false;
+ for_each_perag(mp, agno, pag) {
+ err2 = xfs_ag_resv_init(pag, NULL);
+ if (err2 && !error)
+ error = err2;
+ }
+
+ if (error && error != -ENOSPC) {
+ xfs_warn(mp,
+ "Error %d reserving per-AG metadata reserve pool.", error);
+ xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
+ }
+
+ return error;
+}
+
+/*
+ * Free space reserved for per-AG metadata.
+ */
+int
+xfs_fs_unreserve_ag_blocks(
+ struct xfs_mount *mp)
+{
+ xfs_agnumber_t agno;
+ struct xfs_perag *pag;
+ int error = 0;
+ int err2;
+
+ for_each_perag(mp, agno, pag) {
+ err2 = xfs_ag_resv_free(pag);
+ if (err2 && !error)
+ error = err2;
+ }
+
+ if (error)
+ xfs_warn(mp,
+ "Error %d freeing per-AG metadata reserve pool.", error);
+
+ return error;
+}