If the tracking of live blocks is enabled, the information passed to
the kernel with the set_suinfo ioctl must also be modified. To this
end the nilfs_count_nlive_blks() fucntion is introduced. It simply
loops through the vdescv and bdescv vectors and counts the live
blocks belonging to a certain segment. Here the new vdesc flags
introduced earlier come in handy. If NILFS_VDESC_SNAPSHOT_PROTECTED flag
is set, the block is always counted as alive. However if it is not set
and NILFS_VDESC_PERIOD_PROTECTED is set instead it is counted as
reclaimable.
Additionally the nilfs_xreclaim_segment() function is refactored, so
that the set_suinfo part is extracted into its own function
nilfs_try_set_suinfo(). This is useful, because the code gets more
complicated with the new additions.
If the kernel either doesn't support the set_suinfo ioctl or doesn't
support the set_nlive_blks flag, it returns ENOTTY or EINVAL
respectively and the corresponding options are disabled and not used
again.
Signed-off-by: Andreas Rohner <andreas.rohner@xxxxxxx>
---
include/nilfs.h | 6 ++
lib/gc.c | 177 ++++++++++++++++++++++++++++++++++++++++++++------------
2 files changed, 145 insertions(+), 38 deletions(-)
diff --git a/include/nilfs.h b/include/nilfs.h
index dbcb76e..5fd01fc 100644
--- a/include/nilfs.h
+++ b/include/nilfs.h
@@ -328,6 +328,12 @@ static inline __u32 nilfs_get_blocks_per_segment(const struct nilfs *nilfs)
return le32_to_cpu(nilfs->n_sb->s_blocks_per_segment);
}
+static inline __u64
+nilfs_get_segnum_of_block(const struct nilfs *nilfs, sector_t blocknr)
+{
+ return blocknr / nilfs_get_blocks_per_segment(nilfs);
+}
+
static inline int nilfs_feature_track_live_blks(const struct nilfs *nilfs)
{
const __u64 required_bits = NILFS_FEATURE_COMPAT_TRACK_LIVE_BLKS |
diff --git a/lib/gc.c b/lib/gc.c
index a830e45..3e3bb2c 100644
--- a/lib/gc.c
+++ b/lib/gc.c
@@ -619,6 +619,130 @@ static int nilfs_toss_bdescs(struct nilfs_vector *bdescv)
}
/**
+ * nilfs_count_nlive_blks - returns the number of live blocks in segnum
+ * @nilfs: nilfs object
+ * @segnum: segment number
+ * @bdescv: vector object storing (descriptors of) disk block numbers
+ * @vdescv: vector object storing (descriptors of) virtual block numbers
+ */
+static size_t nilfs_count_nlive_blks(const struct nilfs *nilfs,
+ __u64 segnum,
+ struct nilfs_vector *vdescv,
+ struct nilfs_vector *bdescv,
+ size_t *pnss)
+{
+ struct nilfs_vdesc *vdesc;
+ struct nilfs_bdesc *bdesc;
+ int i;
+ size_t res = 0, nss = 0;
+
+ for (i = 0; i < nilfs_vector_get_size(bdescv); i++) {
+ bdesc = nilfs_vector_get_element(bdescv, i);
+ assert(bdesc != NULL);
+
+ if (nilfs_get_segnum_of_block(nilfs, bdesc->bd_blocknr) ==
+ segnum && nilfs_bdesc_is_live(bdesc))
+ ++res;
+ }
+
+ for (i = 0; i < nilfs_vector_get_size(vdescv); i++) {
+ vdesc = nilfs_vector_get_element(vdescv, i);
+ assert(vdesc != NULL);
+
+ if (nilfs_get_segnum_of_block(nilfs, vdesc->vd_blocknr) ==
+ segnum && (nilfs_vdesc_snapshot_protected(vdesc) ||
+ !nilfs_vdesc_period_protected(vdesc))) {
+ ++res;
+ if (nilfs_vdesc_snapshot_protected(vdesc))
+ ++nss;
+ }
+ }
+
+ if (pnss)
+ *pnss = nss;
+
+ return res;
+}
+
+/**
+ * nilfs_try_set_suinfo - wrapper for nilfs_set_suinfo
+ * @nilfs: nilfs object
+ * @segnums: array of segment numbers storing selected segments
+ * @nsegs: size of the @segnums array
+ * @vdescv: vector object storing (descriptors of) virtual block numbers
+ * @bdescv: vector object storing (descriptors of) disk block numbers
+ *
+ * Description: nilfs_try_set_suinfo() prepares the input data structure
+ * for nilfs_set_suinfo(). If the kernel doesn't support the
+ * NILFS_IOCTL_SET_SUINFO ioctl, errno is set to ENOTTY and the set_suinfo
+ * option is cleared to prevent future calls to nilfs_try_set_suinfo().
+ * Similarly if the SUFILE extension is not supported by the kernel,
+ * errno is set to EINVAL and the track_live_blks option is disabled.
+ *
+ * Return Value: On success, zero is returned. On error, a negative value
+ * is returned. If errno is set to ENOTTY or EINVAL, the kernel doesn't support
+ * the current configuration for nilfs_set_suinfo().
+ */
+static int nilfs_try_set_suinfo(struct nilfs *nilfs, __u64 *segnums,
+ size_t nsegs, struct nilfs_vector *vdescv,
+ struct nilfs_vector *bdescv)
+{
+ struct nilfs_vector *supv;
+ struct nilfs_suinfo_update *sup;
+ struct timeval tv;
+ int ret = -1;
+ size_t i, nblocks, nss;
+
+ supv = nilfs_vector_create(sizeof(struct nilfs_suinfo_update));
+ if (!supv)
+ goto out;
+
+ ret = gettimeofday(&tv, NULL);
+ if (ret < 0)
+ goto out;
+
+ for (i = 0; i < nsegs; ++i) {
+ sup = nilfs_vector_get_new_element(supv);
+ if (!sup) {
+ ret = -1;
+ goto out;
+ }
+
+ sup->sup_segnum = segnums[i];
+ sup->sup_flags = 0;
+ nilfs_suinfo_update_set_lastmod(sup);
+ sup->sup_sui.sui_lastmod = tv.tv_sec;
+
+ if (nilfs_opt_test_track_live_blks(nilfs)) {
+ nilfs_suinfo_update_set_nlive_blks(sup);
+ nilfs_suinfo_update_set_nsnapshot_blks(sup);
+
+ nblocks = nilfs_count_nlive_blks(nilfs,
+ segnums[i], vdescv, bdescv, &nss);
+ sup->sup_sui.sui_nlive_blks = nblocks;
+ sup->sup_sui.sui_nsnapshot_blks = nss;
+ }
+ }
+
+ ret = nilfs_set_suinfo(nilfs, nilfs_vector_get_data(supv), nsegs);
+ if (ret < 0) {
+ if (errno == ENOTTY) {
+ nilfs_gc_logger(LOG_WARNING,
+ "set_suinfo ioctl is not supported");
+ nilfs_opt_clear_set_suinfo(nilfs);
+ } else if (errno == EINVAL) {
+ nilfs_gc_logger(LOG_WARNING,
+ "sufile extension is not supported");
+ nilfs_opt_clear_track_live_blks(nilfs);
+ }
+ }
+
+out:
+ nilfs_vector_destroy(supv);
+ return ret;
+}
+
+/**
* nilfs_xreclaim_segment - reclaim segments (enhanced API)
* @nilfs: nilfs object
* @segnums: array of segment numbers storing selected segments
@@ -632,14 +756,12 @@ int nilfs_xreclaim_segment(struct nilfs *nilfs,
const struct nilfs_reclaim_params *params,
struct nilfs_reclaim_stat *stat)
{
- struct nilfs_vector *vdescv, *bdescv, *periodv, *vblocknrv, *supv;
+ struct nilfs_vector *vdescv, *bdescv, *periodv, *vblocknrv;
sigset_t sigset, oldset, waitset;
nilfs_cno_t protcno;
- ssize_t n, i, ret = -1;
+ ssize_t n, ret = -1;
size_t nblocks;
__u32 reclaimable_blocks;
- struct nilfs_suinfo_update *sup;
- struct timeval tv;
if (!(params->flags & NILFS_RECLAIM_PARAM_PROTSEQ) ||
(params->flags & (~0UL << __NR_NILFS_RECLAIM_PARAMS))) {
@@ -658,8 +780,7 @@ int nilfs_xreclaim_segment(struct nilfs *nilfs,
bdescv = nilfs_vector_create(sizeof(struct nilfs_bdesc));
periodv = nilfs_vector_create(sizeof(struct nilfs_period));
vblocknrv = nilfs_vector_create(sizeof(__u64));
- supv = nilfs_vector_create(sizeof(struct nilfs_suinfo_update));
- if (!vdescv || !bdescv || !periodv || !vblocknrv || !supv)
+ if (!vdescv || !bdescv || !periodv || !vblocknrv)
goto out_vec;
sigemptyset(&sigset);
@@ -757,46 +878,27 @@ int nilfs_xreclaim_segment(struct nilfs *nilfs,
if ((params->flags & NILFS_RECLAIM_PARAM_MIN_RECLAIMABLE_BLKS) &&
nilfs_opt_test_set_suinfo(nilfs) &&
reclaimable_blocks < params->min_reclaimable_blks * n) {
- if (stat) {
- stat->deferred_segs = n;
- stat->cleaned_segs = 0;
- }
- ret = gettimeofday(&tv, NULL);
- if (ret < 0)
+ ret = nilfs_try_set_suinfo(nilfs, segnums, n, vdescv, bdescv);
+ if (ret == 0) {
+ if (stat) {
+ stat->deferred_segs = n;
+ stat->cleaned_segs = 0;
+ }
goto out_lock;
-
- for (i = 0; i < n; ++i) {
- sup = nilfs_vector_get_new_element(supv);
- if (!sup)
- goto out_lock;
-
- sup->sup_segnum = segnums[i];
- sup->sup_flags = 0;
- nilfs_suinfo_update_set_lastmod(sup);
- sup->sup_sui.sui_lastmod = tv.tv_sec;
}
- ret = nilfs_set_suinfo(nilfs, nilfs_vector_get_data(supv), n);
-
- if (ret == 0)
- goto out_lock;
-
- if (ret < 0 && errno != ENOTTY) {
+ if (ret < 0 && errno != ENOTTY && errno != EINVAL) {
nilfs_gc_logger(LOG_ERR, "cannot set suinfo: %s",
strerror(errno));
goto out_lock;
}
- /* errno == ENOTTY */
- nilfs_gc_logger(LOG_WARNING,
- "set_suinfo ioctl is not supported");
- nilfs_opt_clear_set_suinfo(nilfs);
- if (stat) {
- stat->deferred_segs = 0;
- stat->cleaned_segs = n;
- }
- /* Try nilfs_clean_segments */
+ /*
+ * errno == ENOTTY || errno == EINVAL
+ * nilfs_try_set_suinfo() failed because it is not supported
+ * so try nilfs_clean_segments() instead
+ */
}
ret = nilfs_clean_segments(nilfs,
@@ -829,7 +931,6 @@ out_vec:
nilfs_vector_destroy(bdescv);
nilfs_vector_destroy(periodv);
nilfs_vector_destroy(vblocknrv);
- nilfs_vector_destroy(supv);
/*
* Flags of valid fields in stat->exflags must be unset.
*/
--
2.3.7
--
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