xfs: wire up getfsmap to the realtime reverse mapping btree

Connect the getfsmap ioctl to the realtime rmapbt.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c
index 01a97ca7856518b598dfdc8eeea212a77b315374..507f0b9304588251670e19eedf7cf118cd20f834 100644 (file)
--- a/fs/xfs/xfs_fsmap.c
+++ b/fs/xfs/xfs_fsmap.c
@@ -26,6 +26,7 @@
 #include "xfs_rtbitmap.h"
 #include "xfs_ag.h"
 #include "xfs_rtgroup.h"
+#include "xfs_rtrmap_btree.h"
 
 /* Convert an xfs_fsmap to an fsmap. */
 static void
@@ -832,6 +833,179 @@ xfs_getfsmap_rtdev_rtbitmap(
 
        return error;
 }
+
+/* Transform a realtime rmapbt record into a fsmap */
+STATIC int
+xfs_getfsmap_rtdev_rmapbt_helper(
+       struct xfs_btree_cur            *cur,
+       const struct xfs_rmap_irec      *rec,
+       void                            *priv)
+{
+       struct xfs_fsmap_irec           frec = {
+               .owner                  = rec->rm_owner,
+               .offset                 = rec->rm_offset,
+               .rm_flags               = rec->rm_flags,
+               .rec_key                = rec->rm_startblock,
+       };
+       struct xfs_getfsmap_info        *info = priv;
+
+       return xfs_getfsmap_group_helper(info, cur->bc_tp, cur->bc_group,
+                       rec->rm_startblock, rec->rm_blockcount, &frec);
+}
+
+/* Actually query the rtrmap btree. */
+STATIC int
+xfs_getfsmap_rtdev_rmapbt_query(
+       struct xfs_trans                *tp,
+       struct xfs_getfsmap_info        *info,
+       struct xfs_btree_cur            **curpp)
+{
+       struct xfs_rtgroup              *rtg = to_rtg(info->group);
+
+       /* Report any gap at the end of the last rtgroup. */
+       if (info->last)
+               return xfs_getfsmap_rtdev_rmapbt_helper(*curpp, &info->high,
+                               info);
+
+       /* Query the rtrmapbt */
+       xfs_rtgroup_lock(rtg, XFS_RTGLOCK_RMAP);
+       *curpp = xfs_rtrmapbt_init_cursor(tp, rtg);
+       return xfs_rmap_query_range(*curpp, &info->low, &info->high,
+                       xfs_getfsmap_rtdev_rmapbt_helper, info);
+}
+
+/* Execute a getfsmap query against the realtime device rmapbt. */
+STATIC int
+xfs_getfsmap_rtdev_rmapbt(
+       struct xfs_trans                *tp,
+       const struct xfs_fsmap          *keys,
+       struct xfs_getfsmap_info        *info)
+{
+       struct xfs_mount                *mp = tp->t_mountp;
+       struct xfs_rtgroup              *rtg = NULL;
+       struct xfs_btree_cur            *bt_cur = NULL;
+       xfs_rtblock_t                   start_rtb;
+       xfs_rtblock_t                   end_rtb;
+       xfs_rgnumber_t                  start_rg, end_rg;
+       uint64_t                        eofs;
+       int                             error = 0;
+
+       eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
+       if (keys[0].fmr_physical >= eofs)
+               return 0;
+       start_rtb = xfs_daddr_to_rtb(mp, keys[0].fmr_physical);
+       end_rtb = xfs_daddr_to_rtb(mp, min(eofs - 1, keys[1].fmr_physical));
+
+       info->missing_owner = XFS_FMR_OWN_FREE;
+
+       /*
+        * Convert the fsmap low/high keys to rtgroup based keys.  Initialize
+        * low to the fsmap low key and max out the high key to the end
+        * of the rtgroup.
+        */
+       info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset);
+       error = xfs_fsmap_owner_to_rmap(&info->low, &keys[0]);
+       if (error)
+               return error;
+       info->low.rm_blockcount = XFS_BB_TO_FSBT(mp, keys[0].fmr_length);
+       xfs_getfsmap_set_irec_flags(&info->low, &keys[0]);
+
+       /* Adjust the low key if we are continuing from where we left off. */
+       if (info->low.rm_blockcount == 0) {
+               /* No previous record from which to continue */
+       } else if (rmap_not_shareable(mp, &info->low)) {
+               /* Last record seen was an unshareable extent */
+               info->low.rm_owner = 0;
+               info->low.rm_offset = 0;
+
+               start_rtb += info->low.rm_blockcount;
+               if (xfs_rtb_to_daddr(mp, start_rtb) >= eofs)
+                       return 0;
+       } else {
+               /* Last record seen was a shareable file data extent */
+               info->low.rm_offset += info->low.rm_blockcount;
+       }
+       info->low.rm_startblock = xfs_rtb_to_rgbno(mp, start_rtb);
+
+       info->high.rm_startblock = -1U;
+       info->high.rm_owner = ULLONG_MAX;
+       info->high.rm_offset = ULLONG_MAX;
+       info->high.rm_blockcount = 0;
+       info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS;
+
+       start_rg = xfs_rtb_to_rgno(mp, start_rtb);
+       end_rg = xfs_rtb_to_rgno(mp, end_rtb);
+
+       while ((rtg = xfs_rtgroup_next_range(mp, rtg, start_rg, end_rg))) {
+               /*
+                * Set the rtgroup high key from the fsmap high key if this
+                * is the last rtgroup that we're querying.
+                */
+               info->group = &rtg->rtg_group;
+               if (rtg_rgno(rtg) == end_rg) {
+                       info->high.rm_startblock =
+                               xfs_rtb_to_rgbno(mp, end_rtb);
+                       info->high.rm_offset =
+                               XFS_BB_TO_FSBT(mp, keys[1].fmr_offset);
+                       error = xfs_fsmap_owner_to_rmap(&info->high, &keys[1]);
+                       if (error)
+                               break;
+                       xfs_getfsmap_set_irec_flags(&info->high, &keys[1]);
+               }
+
+               if (bt_cur) {
+                       xfs_rtgroup_unlock(to_rtg(bt_cur->bc_group),
+                                       XFS_RTGLOCK_RMAP);
+                       xfs_btree_del_cursor(bt_cur, XFS_BTREE_NOERROR);
+                       bt_cur = NULL;
+               }
+
+               trace_xfs_fsmap_low_group_key(mp, info->dev, rtg_rgno(rtg),
+                               &info->low);
+               trace_xfs_fsmap_high_group_key(mp, info->dev, rtg_rgno(rtg),
+                               &info->high);
+
+               error = xfs_getfsmap_rtdev_rmapbt_query(tp, info, &bt_cur);
+               if (error)
+                       break;
+
+               /*
+                * Set the rtgroup low key to the start of the rtgroup prior to
+                * moving on to the next rtgroup.
+                */
+               if (rtg_rgno(rtg) == start_rg)
+                       memset(&info->low, 0, sizeof(info->low));
+
+               /*
+                * If this is the last rtgroup, report any gap at the end of it
+                * before we drop the reference to the perag when the loop
+                * terminates.
+                */
+               if (rtg_rgno(rtg) == end_rg) {
+                       info->last = true;
+                       error = xfs_getfsmap_rtdev_rmapbt_query(tp, info,
+                                       &bt_cur);
+                       if (error)
+                               break;
+               }
+               info->group = NULL;
+       }
+
+       if (bt_cur) {
+               xfs_rtgroup_unlock(to_rtg(bt_cur->bc_group),
+                               XFS_RTGLOCK_RMAP);
+               xfs_btree_del_cursor(bt_cur, error < 0 ? XFS_BTREE_ERROR :
+                                                        XFS_BTREE_NOERROR);
+       }
+
+       /* loop termination case */
+       if (rtg) {
+               info->group = NULL;
+               xfs_rtgroup_rele(rtg);
+       }
+
+       return error;
+}
 #endif /* CONFIG_XFS_RT */
 
 /* Do we recognize the device? */
@@ -968,7 +1142,10 @@ xfs_getfsmap(
        if (mp->m_rtdev_targp) {
                handlers[2].nr_sectors = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
                handlers[2].dev = new_encode_dev(mp->m_rtdev_targp->bt_dev);
-               handlers[2].fn = xfs_getfsmap_rtdev_rtbitmap;
+               if (use_rmap)
+                       handlers[2].fn = xfs_getfsmap_rtdev_rmapbt;
+               else
+                       handlers[2].fn = xfs_getfsmap_rtdev_rtbitmap;
        }
 #endif /* CONFIG_XFS_RT */