Merge branch 'bugfixes'

* bugfixes:
  pNFS/flexfiles: Fix an XDR encoding bug in layoutreturn
  pNFS/flexfiles: Improve merging of errors in LAYOUTRETURN

2 files changed, 42 insertions, 63 deletions

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index 6594e9f903a0..5bcd92d50e82 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -1948,11 +1948,9 @@ ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
         start = xdr_reserve_space(xdr, 4);
         BUG_ON(!start);
 
-        if (ff_layout_encode_ioerr(flo, xdr, args))
-                goto out;
-
+        ff_layout_encode_ioerr(flo, xdr, args);
         ff_layout_encode_iostats(flo, xdr, args);
-out:
+
         *start = cpu_to_be32((xdr->p - start - 1) * 4);
         dprintk("%s: Return\n", __func__);
 }
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index bd0327541366..29898a9550fa 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -218,63 +218,55 @@ static void extend_ds_error(struct nfs4_ff_layout_ds_err *err,
         err->length = end - err->offset;
 }
 
-static bool ds_error_can_merge(struct nfs4_ff_layout_ds_err *err,  u64 offset,
-                               u64 length, int status, enum nfs_opnum4 opnum,
-                               nfs4_stateid *stateid,
-                               struct nfs4_deviceid *deviceid)
+static int
+ff_ds_error_match(const struct nfs4_ff_layout_ds_err *e1,
+                const struct nfs4_ff_layout_ds_err *e2)
 {
-        return err->status == status && err->opnum == opnum &&
-               nfs4_stateid_match(&err->stateid, stateid) &&
-               !memcmp(&err->deviceid, deviceid, sizeof(*deviceid)) &&
-               end_offset(err->offset, err->length) >= offset &&
-               err->offset <= end_offset(offset, length);
-}
-
-static bool merge_ds_error(struct nfs4_ff_layout_ds_err *old,
-                           struct nfs4_ff_layout_ds_err *new)
-{
-        if (!ds_error_can_merge(old, new->offset, new->length, new->status,
-                                new->opnum, &new->stateid, &new->deviceid))
-                return false;
-
-        extend_ds_error(old, new->offset, new->length);
-        return true;
+        int ret;
+
+        if (e1->opnum != e2->opnum)
+                return e1->opnum < e2->opnum ? -1 : 1;
+        if (e1->status != e2->status)
+                return e1->status < e2->status ? -1 : 1;
+        ret = memcmp(&e1->stateid, &e2->stateid, sizeof(e1->stateid));
+        if (ret != 0)
+                return ret;
+        ret = memcmp(&e1->deviceid, &e2->deviceid, sizeof(e1->deviceid));
+        if (ret != 0)
+                return ret;
+        if (end_offset(e1->offset, e1->length) < e2->offset)
+                return -1;
+        if (e1->offset > end_offset(e2->offset, e2->length))
+                return 1;
+        /* If ranges overlap or are contiguous, they are the same */
+        return 0;
 }
 
-static bool
+static void
 ff_layout_add_ds_error_locked(struct nfs4_flexfile_layout *flo,
                               struct nfs4_ff_layout_ds_err *dserr)
 {
-        struct nfs4_ff_layout_ds_err *err;
-
-        list_for_each_entry(err, &flo->error_list, list) {
-                if (merge_ds_error(err, dserr)) {
-                        return true;
-                }
-        }
-
-        list_add(&dserr->list, &flo->error_list);
-        return false;
-}
-
-static bool
-ff_layout_update_ds_error(struct nfs4_flexfile_layout *flo, u64 offset,
-                          u64 length, int status, enum nfs_opnum4 opnum,
-                          nfs4_stateid *stateid, struct nfs4_deviceid *deviceid)
-{
-        bool found = false;
-        struct nfs4_ff_layout_ds_err *err;
-
-        list_for_each_entry(err, &flo->error_list, list) {
-                if (ds_error_can_merge(err, offset, length, status, opnum,
-                                       stateid, deviceid)) {
-                        found = true;
-                        extend_ds_error(err, offset, length);
+        struct nfs4_ff_layout_ds_err *err, *tmp;
+        struct list_head *head = &flo->error_list;
+        int match;
+
+        /* Do insertion sort w/ merges */
+        list_for_each_entry_safe(err, tmp, &flo->error_list, list) {
+                match = ff_ds_error_match(err, dserr);
+                if (match < 0)
+                        continue;
+                if (match > 0) {
+                        /* Add entry "dserr" _before_ entry "err" */
+                        head = &err->list;
                         break;
                 }
+                /* Entries match, so merge "err" into "dserr" */
+                extend_ds_error(dserr, err->offset, err->length);
+                list_del(&err->list);
+                kfree(err);
         }
 
-        return found;
+        list_add_tail(&dserr->list, head);
 }
 
 int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
@@ -283,7 +275,6 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
                              gfp_t gfp_flags)
 {
         struct nfs4_ff_layout_ds_err *dserr;
-        bool needfree;
 
         if (status == 0)
                 return 0;
@@ -291,14 +282,6 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
         if (mirror->mirror_ds == NULL)
                 return -EINVAL;
 
-        spin_lock(&flo->generic_hdr.plh_inode->i_lock);
-        if (ff_layout_update_ds_error(flo, offset, length, status, opnum,
-                                      &mirror->stateid,
-                                      &mirror->mirror_ds->id_node.deviceid)) {
-                spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
-                return 0;
-        }
-        spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
         dserr = kmalloc(sizeof(*dserr), gfp_flags);
         if (!dserr)
                 return -ENOMEM;
@@ -313,10 +296,8 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
                NFS4_DEVICEID4_SIZE);
 
         spin_lock(&flo->generic_hdr.plh_inode->i_lock);
-        needfree = ff_layout_add_ds_error_locked(flo, dserr);
+        ff_layout_add_ds_error_locked(flo, dserr);
         spin_unlock(&flo->generic_hdr.plh_inode->i_lock);
-        if (needfree)
-                kfree(dserr);
 
         return 0;
 }