xfs: check that the rtrmapbt maxlevels doesn't increase when growing fs

The size of filesystem transaction reservations depends on the maximum
height (maxlevels) of the realtime btrees.  Since we don't want a grow
operation to increase the reservation size enough that we'll fail the
minimum log size checks on the next mount, constrain growfs operations
if they would cause an increase in those maxlevels.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index e1145107d8cbd1697784dd19c9c57958f1d035fd..9df5a09c0acd3b3c7d4966869a7d660b67aa6f5e 100644 (file)
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -22,6 +22,7 @@
 #include "xfs_ag_resv.h"
 #include "xfs_trace.h"
 #include "xfs_rtalloc.h"
+#include "xfs_rtrmap_btree.h"
 
 /*
  * Write new AG headers to disk. Non-transactional, but need to be
@@ -114,6 +115,12 @@ xfs_growfs_data_private(
                xfs_buf_relse(bp);
        }
 
+       /* Make sure the new fs size won't cause problems with the log. */
+       error = xfs_growfs_check_rtgeom(mp, nb, mp->m_sb.sb_rblocks,
+                       mp->m_sb.sb_rextsize);
+       if (error)
+               return error;
+
        nb_div = nb;
        nb_mod = do_div(nb_div, mp->m_sb.sb_agblocks);
        if (nb_mod && nb_mod >= XFS_MIN_AG_BLOCKS)
@@ -221,7 +228,11 @@ xfs_growfs_data_private(
                error = xfs_fs_reserve_ag_blocks(mp);
                if (error == -ENOSPC)
                        error = 0;
+
+               /* Compute new maxlevels for rt btrees. */
+               xfs_rtrmapbt_compute_maxlevels(mp);
        }
+
        return error;
 
 out_trans_cancel:

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index c7efd9264139817e13a25410f102f8ac34d304bb..3c1bce5a4855f2118665b5d21cf692dc46bdd895 100644 (file)
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -989,9 +989,11 @@ xfs_growfs_rt_bmblock(
                goto out_free;
 
        /*
-        * Ensure the mount RT feature flag is now set.
+        * Ensure the mount RT feature flag is now set, and compute new
+        * maxlevels for rt btrees.
         */
        mp->m_features |= XFS_FEAT_REALTIME;
+       xfs_rtrmapbt_compute_maxlevels(mp);
 
        kfree(nmp);
        return 0;
@@ -1159,29 +1161,37 @@ out_rele:
        return error;
 }
 
-static int
+int
 xfs_growfs_check_rtgeom(
        const struct xfs_mount  *mp,
+       xfs_rfsblock_t          dblocks,
        xfs_rfsblock_t          rblocks,
        xfs_extlen_t            rextsize)
 {
+       xfs_extlen_t            min_logfsbs;
        struct xfs_mount        *nmp;
-       int                     error = 0;
 
        nmp = xfs_growfs_rt_alloc_fake_mount(mp, rblocks, rextsize);
        if (!nmp)
                return -ENOMEM;
+       nmp->m_sb.sb_dblocks = dblocks;
+
+       xfs_rtrmapbt_compute_maxlevels(nmp);
+       xfs_trans_resv_calc(nmp, M_RES(nmp));
 
        /*
         * New summary size can't be more than half the size of the log.  This
         * prevents us from getting a log overflow, since we'll log basically
         * the whole summary file at once.
         */
-       if (nmp->m_rsumblocks > (mp->m_sb.sb_logblocks >> 1))
-               error = -EINVAL;
+       min_logfsbs = min_t(xfs_extlen_t, xfs_log_calc_minimum_size(nmp),
+                       nmp->m_rsumblocks * 2);
 
        kfree(nmp);
-       return error;
+
+       if (min_logfsbs > mp->m_sb.sb_logblocks)
+               return -EINVAL;
+       return 0;
 }
 
 /*
@@ -1300,7 +1310,8 @@ xfs_growfs_rt(
                goto out_unlock;
 
        /* Make sure the new fs size won't cause problems with the log. */
-       error = xfs_growfs_check_rtgeom(mp, in->newblocks, in->extsize);
+       error = xfs_growfs_check_rtgeom(mp, mp->m_sb.sb_dblocks, in->newblocks,
+                       in->extsize);
        if (error)
                goto out_unlock;
 

diff --git a/fs/xfs/xfs_rtalloc.h b/fs/xfs/xfs_rtalloc.h
index d87523e6a550068e436047c9d4eb4b54ced5d6cb..9044f7226ab6fc0352a38665a67d85ecadec9696 100644 (file)
--- a/fs/xfs/xfs_rtalloc.h
+++ b/fs/xfs/xfs_rtalloc.h
@@ -46,6 +46,8 @@ xfs_growfs_rt(
        xfs_growfs_rt_t         *in);   /* user supplied growfs struct */
 
 int xfs_rtalloc_reinit_frextents(struct xfs_mount *mp);
+int xfs_growfs_check_rtgeom(const struct xfs_mount *mp, xfs_rfsblock_t dblocks,
+               xfs_rfsblock_t rblocks, xfs_agblock_t rextsize);
 #else
 # define xfs_growfs_rt(mp,in)                          (-ENOSYS)
 # define xfs_rtalloc_reinit_frextents(m)               (0)
@@ -65,6 +67,14 @@ xfs_rtmount_init(
 # define xfs_rtunmount_inodes(m)
 # define xfs_rt_resv_free(mp)                          ((void)0)
 # define xfs_rt_resv_init(mp)                          (0)
+
+static inline int
+xfs_growfs_check_rtgeom(const struct xfs_mount *mp,
+               xfs_rfsblock_t dblocks, xfs_rfsblock_t rblocks,
+               xfs_extlen_t rextsize)
+{
+       return 0;
+}
 #endif /* CONFIG_XFS_RT */
 
 #endif /* __XFS_RTALLOC_H__ */

diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index a098935163b7c2d6f272ccb0161fbf3f7d289032..84cdc145e2d96af1f81920bc904305537f24f8c2 100644 (file)
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -5622,6 +5622,27 @@ DEFINE_METAFILE_RESV_EVENT(xfs_metafile_resv_free_space);
 DEFINE_METAFILE_RESV_EVENT(xfs_metafile_resv_critical);
 DEFINE_INODE_ERROR_EVENT(xfs_metafile_resv_init_error);
 
+#ifdef CONFIG_XFS_RT
+TRACE_EVENT(xfs_growfs_check_rtgeom,
+       TP_PROTO(const struct xfs_mount *mp, unsigned int min_logfsbs),
+       TP_ARGS(mp, min_logfsbs),
+       TP_STRUCT__entry(
+               __field(dev_t, dev)
+               __field(unsigned int, logblocks)
+               __field(unsigned int, min_logfsbs)
+       ),
+       TP_fast_assign(
+               __entry->dev = mp->m_super->s_dev;
+               __entry->logblocks = mp->m_sb.sb_logblocks;
+               __entry->min_logfsbs = min_logfsbs;
+       ),
+       TP_printk("dev %d:%d logblocks %u min_logfsbs %u",
+                 MAJOR(__entry->dev), MINOR(__entry->dev),
+                 __entry->logblocks,
+                 __entry->min_logfsbs)
+);
+#endif /* CONFIG_XFS_RT */
+
 #endif /* _TRACE_XFS_H */
 
 #undef TRACE_INCLUDE_PATH