btrfs: raid56: do extra dumping for CONFIG_BTRFS_ASSERT

There are several hard-to-hit ASSERT()s hit inside raid56.
Unfortunately the ASSERT() expression is a little complex, and except
the ASSERT(), there is nothing to provide any clue.

Considering if race is involved, it's pretty hard to reproduce.
Meanwhile sometimes the dump of the rbio structure can provide some
pretty good clues, it's worth to do the extra multi-line dump for
btrfs raid56 related code.

The dump looks like this:

  BTRFS critical (device dm-3): bioc logical=4598530048 full_stripe=4598530048 size=0 map_type=0x81 mirror=0 replace_nr_stripes=0 replace_stripe_src=-1 num_stripes=5
  BTRFS critical (device dm-3):     nr=0 devid=1 physical=1166147584
  BTRFS critical (device dm-3):     nr=1 devid=2 physical=1145176064
  BTRFS critical (device dm-3):     nr=2 devid=4 physical=1145176064
  BTRFS critical (device dm-3):     nr=3 devid=5 physical=1145176064
  BTRFS critical (device dm-3):     nr=4 devid=3 physical=1145176064
  BTRFS critical (device dm-3): rbio flags=0x0 nr_sectors=80 nr_data=4 real_stripes=5 stripe_nsectors=16 scrubp=0 dbitmap=0x0
  BTRFS critical (device dm-3): logical=4598530048
  assertion failed: orig_logical >= full_stripe_start && orig_logical + orig_len <= full_stripe_start + rbio->nr_data * BTRFS_STRIPE_LEN, in fs/btrfs/raid56.c:1702

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 98 insertions, 14 deletions

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 831fac45e70f..3858c00936e8 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -40,6 +40,85 @@
 
 #define BTRFS_STRIPE_HASH_TABLE_BITS				11
 
+static void dump_bioc(const struct btrfs_fs_info *fs_info, const struct btrfs_io_context *bioc)
+{
+	if (unlikely(!bioc)) {
+		btrfs_crit(fs_info, "bioc=NULL");
+		return;
+	}
+	btrfs_crit(fs_info,
+"bioc logical=%llu full_stripe=%llu size=%llu map_type=0x%llx mirror=%u replace_nr_stripes=%u replace_stripe_src=%d num_stripes=%u",
+		bioc->logical, bioc->full_stripe_logical, bioc->size,
+		bioc->map_type, bioc->mirror_num, bioc->replace_nr_stripes,
+		bioc->replace_stripe_src, bioc->num_stripes);
+	for (int i = 0; i < bioc->num_stripes; i++) {
+		btrfs_crit(fs_info, "    nr=%d devid=%llu physical=%llu",
+			   i, bioc->stripes[i].dev->devid,
+			   bioc->stripes[i].physical);
+	}
+}
+
+static void btrfs_dump_rbio(const struct btrfs_fs_info *fs_info,
+			    const struct btrfs_raid_bio *rbio)
+{
+	if (!IS_ENABLED(CONFIG_BTRFS_ASSERT))
+		return;
+
+	dump_bioc(fs_info, rbio->bioc);
+	btrfs_crit(fs_info,
+"rbio flags=0x%lx nr_sectors=%u nr_data=%u real_stripes=%u stripe_nsectors=%u scrubp=%u dbitmap=0x%lx",
+		rbio->flags, rbio->nr_sectors, rbio->nr_data,
+		rbio->real_stripes, rbio->stripe_nsectors,
+		rbio->scrubp, rbio->dbitmap);
+}
+
+#define ASSERT_RBIO(expr, rbio)						\
+({									\
+	if (IS_ENABLED(CONFIG_BTRFS_ASSERT) && unlikely(!(expr))) {	\
+		const struct btrfs_fs_info *__fs_info = (rbio)->bioc ?	\
+					(rbio)->bioc->fs_info : NULL;	\
+									\
+		btrfs_dump_rbio(__fs_info, (rbio));			\
+	}								\
+	ASSERT((expr));							\
+})
+
+#define ASSERT_RBIO_STRIPE(expr, rbio, stripe_nr)			\
+({									\
+	if (IS_ENABLED(CONFIG_BTRFS_ASSERT) && unlikely(!(expr))) {	\
+		const struct btrfs_fs_info *__fs_info = (rbio)->bioc ?	\
+					(rbio)->bioc->fs_info : NULL;	\
+									\
+		btrfs_dump_rbio(__fs_info, (rbio));			\
+		btrfs_crit(__fs_info, "stripe_nr=%d", (stripe_nr));	\
+	}								\
+	ASSERT((expr));							\
+})
+
+#define ASSERT_RBIO_SECTOR(expr, rbio, sector_nr)			\
+({									\
+	if (IS_ENABLED(CONFIG_BTRFS_ASSERT) && unlikely(!(expr))) {	\
+		const struct btrfs_fs_info *__fs_info = (rbio)->bioc ?	\
+					(rbio)->bioc->fs_info : NULL;	\
+									\
+		btrfs_dump_rbio(__fs_info, (rbio));			\
+		btrfs_crit(__fs_info, "sector_nr=%d", (sector_nr));	\
+	}								\
+	ASSERT((expr));							\
+})
+
+#define ASSERT_RBIO_LOGICAL(expr, rbio, logical)			\
+({									\
+	if (IS_ENABLED(CONFIG_BTRFS_ASSERT) && unlikely(!(expr))) {	\
+		const struct btrfs_fs_info *__fs_info = (rbio)->bioc ?	\
+					(rbio)->bioc->fs_info : NULL;	\
+									\
+		btrfs_dump_rbio(__fs_info, (rbio));			\
+		btrfs_crit(__fs_info, "logical=%llu", (logical));		\
+	}								\
+	ASSERT((expr));							\
+})
+
 /* Used by the raid56 code to lock stripes for read/modify/write */
 struct btrfs_stripe_hash {
 	struct list_head hash_list;
@@ -592,8 +671,8 @@ static unsigned int rbio_stripe_sector_index(const struct btrfs_raid_bio *rbio,
 					     unsigned int stripe_nr,
 					     unsigned int sector_nr)
 {
-	ASSERT(stripe_nr < rbio->real_stripes);
-	ASSERT(sector_nr < rbio->stripe_nsectors);
+	ASSERT_RBIO_STRIPE(stripe_nr < rbio->real_stripes, rbio, stripe_nr);
+	ASSERT_RBIO_SECTOR(sector_nr < rbio->stripe_nsectors, rbio, sector_nr);
 
 	return stripe_nr * rbio->stripe_nsectors + sector_nr;
 }
@@ -873,8 +952,10 @@ static struct sector_ptr *sector_in_rbio(struct btrfs_raid_bio *rbio,
 	struct sector_ptr *sector;
 	int index;
 
-	ASSERT(stripe_nr >= 0 && stripe_nr < rbio->real_stripes);
-	ASSERT(sector_nr >= 0 && sector_nr < rbio->stripe_nsectors);
+	ASSERT_RBIO_STRIPE(stripe_nr >= 0 && stripe_nr < rbio->real_stripes,
+			   rbio, stripe_nr);
+	ASSERT_RBIO_SECTOR(sector_nr >= 0 && sector_nr < rbio->stripe_nsectors,
+			   rbio, sector_nr);
 
 	index = stripe_nr * rbio->stripe_nsectors + sector_nr;
 	ASSERT(index >= 0 && index < rbio->nr_sectors);
@@ -1057,8 +1138,10 @@ static int rbio_add_io_sector(struct btrfs_raid_bio *rbio,
 	 * thus it can be larger than rbio->real_stripe.
 	 * So here we check against bioc->num_stripes, not rbio->real_stripes.
 	 */
-	ASSERT(stripe_nr >= 0 && stripe_nr < rbio->bioc->num_stripes);
-	ASSERT(sector_nr >= 0 && sector_nr < rbio->stripe_nsectors);
+	ASSERT_RBIO_STRIPE(stripe_nr >= 0 && stripe_nr < rbio->bioc->num_stripes,
+			   rbio, stripe_nr);
+	ASSERT_RBIO_SECTOR(sector_nr >= 0 && sector_nr < rbio->stripe_nsectors,
+			   rbio, sector_nr);
 	ASSERT(sector->page);
 
 	stripe = &rbio->bioc->stripes[stripe_nr];
@@ -1197,14 +1280,14 @@ static void assert_rbio(struct btrfs_raid_bio *rbio)
 	 * At least two stripes (2 disks RAID5), and since real_stripes is U8,
 	 * we won't go beyond 256 disks anyway.
 	 */
-	ASSERT(rbio->real_stripes >= 2);
-	ASSERT(rbio->nr_data > 0);
+	ASSERT_RBIO(rbio->real_stripes >= 2, rbio);
+	ASSERT_RBIO(rbio->nr_data > 0, rbio);
 
 	/*
 	 * This is another check to make sure nr data stripes is smaller
 	 * than total stripes.
 	 */
-	ASSERT(rbio->nr_data < rbio->real_stripes);
+	ASSERT_RBIO(rbio->nr_data < rbio->real_stripes, rbio);
 }
 
 /* Generate PQ for one vertical stripe. */
@@ -1641,9 +1724,10 @@ static void rbio_add_bio(struct btrfs_raid_bio *rbio, struct bio *orig_bio)
 	const u32 sectorsize = fs_info->sectorsize;
 	u64 cur_logical;
 
-	ASSERT(orig_logical >= full_stripe_start &&
-	       orig_logical + orig_len <= full_stripe_start +
-	       rbio->nr_data * BTRFS_STRIPE_LEN);
+	ASSERT_RBIO_LOGICAL(orig_logical >= full_stripe_start &&
+			    orig_logical + orig_len <= full_stripe_start +
+			    rbio->nr_data * BTRFS_STRIPE_LEN,
+			    rbio, orig_logical);
 
 	bio_list_add(&rbio->bio_list, orig_bio);
 	rbio->bio_list_bytes += orig_bio->bi_iter.bi_size;
@@ -2389,7 +2473,7 @@ struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
 			break;
 		}
 	}
-	ASSERT(i < rbio->real_stripes);
+	ASSERT_RBIO_STRIPE(i < rbio->real_stripes, rbio, i);
 
 	bitmap_copy(&rbio->dbitmap, dbitmap, stripe_nsectors);
 	return rbio;
@@ -2555,7 +2639,7 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 	 * Replace is running and our parity stripe needs to be duplicated to
 	 * the target device.  Check we have a valid source stripe number.
 	 */
-	ASSERT(rbio->bioc->replace_stripe_src >= 0);
+	ASSERT_RBIO(rbio->bioc->replace_stripe_src >= 0, rbio);
 	for_each_set_bit(sectornr, pbitmap, rbio->stripe_nsectors) {
 		struct sector_ptr *sector;