libfrog: support vectored scrub

Enhance libfrog to support performing vectored metadata scrub.

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

diff --git a/libfrog/fsgeom.h b/libfrog/fsgeom.h
index f327dc7d70d03a3d66e3ebdf4ba6c79887bd5155..df2ca2a408e78a99e1d50112648eb074b4d277e0 100644 (file)
--- a/libfrog/fsgeom.h
+++ b/libfrog/fsgeom.h
@@ -50,6 +50,12 @@ struct xfs_fd {
 /* Only use v5 bulkstat/inumbers ioctls. */
 #define XFROG_FLAG_BULKSTAT_FORCE_V5   (1 << 1)
 
+/* Only use the older one-at-a-time scrub ioctl. */
+#define XFROG_FLAG_SCRUB_FORCE_SINGLE  (1 << 2)
+
+/* Only use the vectored scrub ioctl. */
+#define XFROG_FLAG_SCRUB_FORCE_VECTOR  (1 << 3)
+
 /* Static initializers */
 #define XFS_FD_INIT(_fd)       { .fd = (_fd), }
 #define XFS_FD_INIT_EMPTY      XFS_FD_INIT(-1)

diff --git a/libfrog/scrub.c b/libfrog/scrub.c
index a2146e228f5b6dbdf7e9aa4d4a2d22dc79078f16..e233c0f9c8e1e669c80fcb27693f95f6c618aac2 100644 (file)
--- a/libfrog/scrub.c
+++ b/libfrog/scrub.c
@@ -171,3 +171,140 @@ xfrog_scrub_metadata(
 
        return 0;
 }
+
+/* Decide if there have been any scrub failures up to this point. */
+static inline int
+xfrog_scrubv_check_barrier(
+       const struct xfs_scrub_vec      *vectors,
+       const struct xfs_scrub_vec      *stop_vec)
+{
+       const struct xfs_scrub_vec      *v;
+       __u32                           failmask;
+
+       failmask = stop_vec->sv_flags & XFS_SCRUB_FLAGS_OUT;
+
+       for (v = vectors; v < stop_vec; v++) {
+               if (v->sv_type == XFS_SCRUB_TYPE_BARRIER)
+                       continue;
+
+               /*
+                * Runtime errors count as a previous failure, except the ones
+                * used to ask userspace to retry.
+                */
+               switch (v->sv_ret) {
+               case -EBUSY:
+               case -ENOENT:
+               case -EUSERS:
+               case 0:
+                       break;
+               default:
+                       return -ECANCELED;
+               }
+
+               /*
+                * If any of the out-flags on the scrub vector match the mask
+                * that was set on the barrier vector, that's a previous fail.
+                */
+               if (v->sv_flags & failmask)
+                       return -ECANCELED;
+       }
+
+       return 0;
+}
+
+static int
+xfrog_scrubv_fallback(
+       struct xfs_fd                   *xfd,
+       struct xfrog_scrubv             *scrubv)
+{
+       struct xfs_scrub_vec            *vectors = scrubv->vectors;
+       struct xfs_scrub_vec            *v;
+       unsigned int                    i;
+
+       if (scrubv->head.svh_flags & ~XFS_SCRUB_VEC_FLAGS_ALL)
+               return -EINVAL;
+
+       foreach_xfrog_scrubv_vec(scrubv, i, v) {
+               if (v->sv_reserved)
+                       return -EINVAL;
+
+               if (v->sv_type == XFS_SCRUB_TYPE_BARRIER &&
+                   (v->sv_flags & ~XFS_SCRUB_FLAGS_OUT))
+                       return -EINVAL;
+       }
+
+       /* Run all the scrubbers. */
+       foreach_xfrog_scrubv_vec(scrubv, i, v) {
+               struct xfs_scrub_metadata       sm = {
+                       .sm_type                = v->sv_type,
+                       .sm_flags               = v->sv_flags,
+                       .sm_ino                 = scrubv->head.svh_ino,
+                       .sm_gen                 = scrubv->head.svh_gen,
+                       .sm_agno                = scrubv->head.svh_agno,
+               };
+               struct timespec tv;
+
+               if (v->sv_type == XFS_SCRUB_TYPE_BARRIER) {
+                       v->sv_ret = xfrog_scrubv_check_barrier(vectors, v);
+                       if (v->sv_ret)
+                               break;
+                       continue;
+               }
+
+               v->sv_ret = xfrog_scrub_metadata(xfd, &sm);
+               v->sv_flags = sm.sm_flags;
+
+               if (scrubv->head.svh_rest_us) {
+                       tv.tv_sec = 0;
+                       tv.tv_nsec = scrubv->head.svh_rest_us * 1000;
+                       nanosleep(&tv, NULL);
+               }
+       }
+
+       return 0;
+}
+
+/* Invoke the vectored scrub ioctl. */
+static int
+xfrog_scrubv_call(
+       struct xfs_fd                   *xfd,
+       struct xfs_scrub_vec_head       *vhead)
+{
+       int                             ret;
+
+       ret = ioctl(xfd->fd, XFS_IOC_SCRUBV_METADATA, vhead);
+       if (ret)
+               return -errno;
+
+       return 0;
+}
+
+/* Invoke the vectored scrub ioctl.  Returns zero or negative error code. */
+int
+xfrog_scrubv_metadata(
+       struct xfs_fd                   *xfd,
+       struct xfrog_scrubv             *scrubv)
+{
+       int                             error = 0;
+
+       if (scrubv->head.svh_nr > XFROG_SCRUBV_MAX_VECTORS)
+               return -EINVAL;
+
+       if (xfd->flags & XFROG_FLAG_SCRUB_FORCE_SINGLE)
+               goto try_single;
+
+       error = xfrog_scrubv_call(xfd, &scrubv->head);
+       if (error == 0 || (xfd->flags & XFROG_FLAG_SCRUB_FORCE_VECTOR))
+               return error;
+
+       /* If the vectored scrub ioctl wasn't found, force single mode. */
+       switch (error) {
+       case -EOPNOTSUPP:
+       case -ENOTTY:
+               xfd->flags |= XFROG_FLAG_SCRUB_FORCE_SINGLE;
+               break;
+       }
+
+try_single:
+       return xfrog_scrubv_fallback(xfd, scrubv);
+}

diff --git a/libfrog/scrub.h b/libfrog/scrub.h
index 27230c62f71aed3ee7ab3c10fa7e45c492d95b3f..b564c0d7bd0f555621fd0c50cd349c3f23e63ada 100644 (file)
--- a/libfrog/scrub.h
+++ b/libfrog/scrub.h
@@ -28,4 +28,39 @@ extern const struct xfrog_scrub_descr xfrog_scrubbers[XFS_SCRUB_TYPE_NR];
 
 int xfrog_scrub_metadata(struct xfs_fd *xfd, struct xfs_scrub_metadata *meta);
 
+/*
+ * Allow enough space to call all scrub types with a barrier between each.
+ * This is overkill for every caller in xfsprogs.
+ */
+#define XFROG_SCRUBV_MAX_VECTORS       (XFS_SCRUB_TYPE_NR * 2)
+
+struct xfrog_scrubv {
+       struct xfs_scrub_vec_head       head;
+       struct xfs_scrub_vec            vectors[XFROG_SCRUBV_MAX_VECTORS];
+};
+
+/* Initialize a scrubv structure; callers must have zeroed @scrubv. */
+static inline void
+xfrog_scrubv_init(struct xfrog_scrubv *scrubv)
+{
+       scrubv->head.svh_vectors = (uintptr_t)scrubv->vectors;
+}
+
+/* Return the next free vector from the scrubv structure. */
+static inline struct xfs_scrub_vec *
+xfrog_scrubv_next_vector(struct xfrog_scrubv *scrubv)
+{
+       if (scrubv->head.svh_nr >= XFROG_SCRUBV_MAX_VECTORS)
+               return NULL;
+
+       return &scrubv->vectors[scrubv->head.svh_nr++];
+}
+
+#define foreach_xfrog_scrubv_vec(scrubv, i, vec) \
+       for ((i) = 0, (vec) = (scrubv)->vectors; \
+            (i) < (scrubv)->head.svh_nr; \
+            (i)++, (vec)++)
+
+int xfrog_scrubv_metadata(struct xfs_fd *xfd, struct xfrog_scrubv *scrubv);
+
 #endif /* __LIBFROG_SCRUB_H__ */