If a filesystem is going to only be used read-only, and will be a
deployable image, we can strip out alloc info for a substantial
reduction in metadata size - around half, due to backpointers.
Alloc info will be regenerated on first read-write mount.
Remounting RW is disallowed for now, since we don't yet have
check_allocations running in RW mode.
Signed-off-by: Kent Overstreet <kent.overstr...@linux.dev>
---
fs/bcachefs/bcachefs_format.h | 3 ++-
fs/bcachefs/errcode.h | 1 +
fs/bcachefs/recovery.c | 28 ++++++++++++++++++++++------
fs/bcachefs/recovery.h | 1 +
fs/bcachefs/recovery_passes.c | 14 +++++++++++++-
fs/bcachefs/recovery_passes_types.h | 18 ++++++++++--------
fs/bcachefs/sb-members.c | 6 ++++++
fs/bcachefs/super.c | 6 ++++++
8 files changed, 61 insertions(+), 16 deletions(-)
diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h
index e6203665f230..7e2debc40045 100644
--- a/fs/bcachefs/bcachefs_format.h
+++ b/fs/bcachefs/bcachefs_format.h
@@ -918,7 +918,8 @@ static inline void
SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE(struct bch_sb *sb, __u
x(alloc_v2, 17) \
x(extents_across_btree_nodes, 18) \
x(incompat_version_field, 19) \
- x(casefolding, 20)
+ x(casefolding, 20) \
+ x(no_alloc_info, 21)
#define BCH_SB_FEATURES_ALWAYS \
(BIT_ULL(BCH_FEATURE_new_extent_overwrite)| \
diff --git a/fs/bcachefs/errcode.h b/fs/bcachefs/errcode.h
index 4a040085454c..e54c8264e7e1 100644
--- a/fs/bcachefs/errcode.h
+++ b/fs/bcachefs/errcode.h
@@ -221,6 +221,7 @@
x(EROFS, erofs_unfixed_errors)
\
x(EROFS, erofs_norecovery)
\
x(EROFS, erofs_nochanges)
\
+ x(EROFS, erofs_no_alloc_info)
\
x(EROFS, insufficient_devices)
\
x(0, operation_blocked)
\
x(BCH_ERR_operation_blocked, btree_cache_cannibalize_lock_blocked)
\
diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index 58ee1ebdcbaa..fbe2e6406f53 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -32,7 +32,6 @@
#include <linux/sort.h>
#include <linux/stat.h>
-
int bch2_btree_lost_data(struct bch_fs *c, enum btree_id btree)
{
u64 b = BIT_ULL(btree);
@@ -113,11 +112,8 @@ static void kill_btree(struct bch_fs *c, enum btree_id
btree)
}
/* for -o reconstruct_alloc: */
-static void bch2_reconstruct_alloc(struct bch_fs *c)
+void bch2_reconstruct_alloc(struct bch_fs *c)
{
- bch2_journal_log_msg(c, "dropping alloc info");
- bch_info(c, "dropping and reconstructing all alloc info");
-
mutex_lock(&c->sb_lock);
struct bch_sb_field_ext *ext = bch2_sb_field_get(c->disk_sb.sb, ext);
@@ -159,6 +155,8 @@ static void bch2_reconstruct_alloc(struct bch_fs *c)
c->opts.recovery_passes |=
bch2_recovery_passes_from_stable(le64_to_cpu(ext->recovery_passes_required[0]));
+ c->disk_sb.sb->features[0] &=
~cpu_to_le64(BIT_ULL(BCH_FEATURE_no_alloc_info));
+
bch2_write_super(c);
mutex_unlock(&c->sb_lock);
@@ -888,8 +886,26 @@ int bch2_fs_recovery(struct bch_fs *c)
if (ret)
goto err;
- if (c->opts.reconstruct_alloc)
+ if (!c->opts.read_only &&
+ (c->sb.features & BIT_ULL(BCH_FEATURE_no_alloc_info))) {
+ bch_info(c, "mounting a filesystem with no alloc info
read-write; will recreate");
+
bch2_reconstruct_alloc(c);
+ } else if (c->opts.reconstruct_alloc) {
+ bch2_journal_log_msg(c, "dropping alloc info");
+ bch_info(c, "dropping and reconstructing all alloc info");
+
+ bch2_reconstruct_alloc(c);
+ }
+
+ if (c->sb.features & BIT_ULL(BCH_FEATURE_no_alloc_info)) {
+ /* We can't go RW to fix errors without alloc info */
+ if (c->opts.fix_errors == FSCK_FIX_yes ||
+ c->opts.fix_errors == FSCK_FIX_ask)
+ c->opts.fix_errors = FSCK_FIX_no;
+ if (c->opts.errors == BCH_ON_ERROR_fix_safe)
+ c->opts.errors = BCH_ON_ERROR_continue;
+ }
/*
* After an unclean shutdown, skip then next few journal sequence
diff --git a/fs/bcachefs/recovery.h b/fs/bcachefs/recovery.h
index b0d55754b21b..d858ba674eaa 100644
--- a/fs/bcachefs/recovery.h
+++ b/fs/bcachefs/recovery.h
@@ -3,6 +3,7 @@
#define _BCACHEFS_RECOVERY_H
int bch2_btree_lost_data(struct bch_fs *, enum btree_id);
+void bch2_reconstruct_alloc(struct bch_fs *);
int bch2_journal_replay(struct bch_fs *);
diff --git a/fs/bcachefs/recovery_passes.c b/fs/bcachefs/recovery_passes.c
index 92e431af9ac3..7a6444088aa6 100644
--- a/fs/bcachefs/recovery_passes.c
+++ b/fs/bcachefs/recovery_passes.c
@@ -46,8 +46,18 @@ static int bch2_set_may_go_rw(struct bch_fs *c)
set_bit(BCH_FS_may_go_rw, &c->flags);
- if (keys->nr || !c->opts.read_only || c->opts.fsck || !c->sb.clean ||
c->opts.recovery_passes)
+ if (keys->nr ||
+ !c->opts.read_only ||
+ !c->sb.clean ||
+ c->opts.recovery_passes ||
+ (c->opts.fsck && !(c->sb.features &
BIT_ULL(BCH_FEATURE_no_alloc_info)))) {
+ if (c->sb.features & BIT_ULL(BCH_FEATURE_no_alloc_info)) {
+ bch_info(c, "mounting a filesystem with no alloc info
read-write; will recreate");
+ bch2_reconstruct_alloc(c);
+ }
+
return bch2_fs_read_write_early(c);
+ }
return 0;
}
@@ -239,6 +249,8 @@ static bool should_run_recovery_pass(struct bch_fs *c, enum
bch_recovery_pass pa
{
struct recovery_pass_fn *p = recovery_pass_fns + pass;
+ if ((p->when & PASS_ALLOC) && (c->sb.features &
BIT_ULL(BCH_FEATURE_no_alloc_info)))
+ return false;
if (c->opts.recovery_passes_exclude & BIT_ULL(pass))
return false;
if (c->opts.recovery_passes & BIT_ULL(pass))
diff --git a/fs/bcachefs/recovery_passes_types.h
b/fs/bcachefs/recovery_passes_types.h
index 4671ccf2d560..f9d565bb50dd 100644
--- a/fs/bcachefs/recovery_passes_types.h
+++ b/fs/bcachefs/recovery_passes_types.h
@@ -7,6 +7,8 @@
#define PASS_UNCLEAN BIT(2)
#define PASS_ALWAYS BIT(3)
#define PASS_ONLINE BIT(4)
+#define PASS_ALLOC BIT(5)
+#define PASS_FSCK_ALLOC (PASS_FSCK|PASS_ALLOC)
#ifdef CONFIG_BCACHEFS_DEBUG
#define PASS_FSCK_DEBUG BIT(1)
@@ -27,17 +29,17 @@
x(stripes_read, 1, 0)
\
x(initialize_subvolumes, 2, 0)
\
x(snapshots_read, 3, PASS_ALWAYS)
\
- x(check_allocations, 5, PASS_FSCK)
\
- x(trans_mark_dev_sbs, 6, PASS_ALWAYS|PASS_SILENT)
\
- x(fs_journal_alloc, 7, PASS_ALWAYS|PASS_SILENT)
\
+ x(check_allocations, 5, PASS_FSCK_ALLOC)
\
+ x(trans_mark_dev_sbs, 6,
PASS_ALWAYS|PASS_SILENT|PASS_ALLOC) \
+ x(fs_journal_alloc, 7,
PASS_ALWAYS|PASS_SILENT|PASS_ALLOC) \
x(set_may_go_rw, 8, PASS_ALWAYS|PASS_SILENT)
\
x(journal_replay, 9, PASS_ALWAYS)
\
- x(check_alloc_info, 10, PASS_ONLINE|PASS_FSCK)
\
- x(check_lrus, 11, PASS_ONLINE|PASS_FSCK)
\
- x(check_btree_backpointers, 12, PASS_ONLINE|PASS_FSCK)
\
+ x(check_alloc_info, 10,
PASS_ONLINE|PASS_FSCK_ALLOC) \
+ x(check_lrus, 11,
PASS_ONLINE|PASS_FSCK_ALLOC) \
+ x(check_btree_backpointers, 12,
PASS_ONLINE|PASS_FSCK_ALLOC) \
x(check_backpointers_to_extents, 13,
PASS_ONLINE|PASS_FSCK_DEBUG) \
- x(check_extents_to_backpointers, 14, PASS_ONLINE|PASS_FSCK)
\
- x(check_alloc_to_lru_refs, 15, PASS_ONLINE|PASS_FSCK)
\
+ x(check_extents_to_backpointers, 14,
PASS_ONLINE|PASS_FSCK_ALLOC) \
+ x(check_alloc_to_lru_refs, 15,
PASS_ONLINE|PASS_FSCK_ALLOC) \
x(fs_freespace_init, 16, PASS_ALWAYS|PASS_SILENT)
\
x(bucket_gens_init, 17, 0)
\
x(reconstruct_snapshots, 38, 0)
\
diff --git a/fs/bcachefs/sb-members.c b/fs/bcachefs/sb-members.c
index cdc4258c3c21..9a82ed3f18f5 100644
--- a/fs/bcachefs/sb-members.c
+++ b/fs/bcachefs/sb-members.c
@@ -188,6 +188,12 @@ static int validate_member(struct printbuf *err,
return -BCH_ERR_invalid_sb_members;
}
+ if (BCH_MEMBER_FREESPACE_INITIALIZED(&m) &&
+ sb->features[0] & BIT_ULL(BCH_FEATURE_no_alloc_info)) {
+ prt_printf(err, "device %u: freespace initialized but fs has no
alloc info", i);
+ return -BCH_ERR_invalid_sb_members;
+ }
+
return 0;
}
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 2d244deb07a8..797601756af1 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -464,6 +464,9 @@ static int __bch2_fs_read_write(struct bch_fs *c, bool
early)
BUG_ON(!test_bit(BCH_FS_may_go_rw, &c->flags));
+ if (WARN_ON(c->sb.features & BIT_ULL(BCH_FEATURE_no_alloc_info)))
+ return -BCH_ERR_erofs_no_alloc_info;
+
if (test_bit(BCH_FS_initial_gc_unfixed, &c->flags)) {
bch_err(c, "cannot go rw, unfixed btree errors");
return -BCH_ERR_erofs_unfixed_errors;
@@ -550,6 +553,9 @@ int bch2_fs_read_write(struct bch_fs *c)
if (c->opts.nochanges)
return -BCH_ERR_erofs_nochanges;
+ if (c->sb.features & BIT_ULL(BCH_FEATURE_no_alloc_info))
+ return -BCH_ERR_erofs_no_alloc_info;
+
return __bch2_fs_read_write(c, false);
}
--
2.49.0
