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bcachefs: Subvolumes, snapshots

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This patch adds subvolume.c - support for the subvolumes and snapshots
btrees and related data types and on disk data structures. The next
patches will start hooking up this new code to existing code.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This commit is contained in:
Kent Overstreet 2021-03-16 00:42:25 -04:00 committed by Kent Overstreet
parent 8948fc8f15
commit 14b393ee76
17 changed files with 1314 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
fs/bcachefs/Makefile
View File

@ -50,6 +50,7 @@ bcachefs-y := \
replicas.o \
siphash.o \
six.o \
subvolume.o \
super.o \
super-io.o \
sysfs.o \

23
fs/bcachefs/bcachefs.h
View File

@ -381,6 +381,8 @@ enum gc_phase {
GC_PHASE_BTREE_alloc,
GC_PHASE_BTREE_quotas,
GC_PHASE_BTREE_reflink,
GC_PHASE_BTREE_subvolumes,
GC_PHASE_BTREE_snapshots,
GC_PHASE_PENDING_DELETE,
};
@ -564,6 +566,21 @@ struct btree_path_buf {
#define REPLICAS_DELTA_LIST_MAX (1U << 16)
struct snapshot_t {
u32 parent;
u32 children[2];
u32 subvol; /* Nonzero only if a subvolume points to this node: */
u32 equiv;
};
typedef struct {
u32 subvol;
u64 inum;
} subvol_inum;
#define BCACHEFS_ROOT_SUBVOL_INUM \
((subvol_inum) { BCACHEFS_ROOT_SUBVOL, BCACHEFS_ROOT_INO })
struct bch_fs {
struct closure cl;
@ -635,6 +652,12 @@ struct bch_fs {
struct closure sb_write;
struct mutex sb_lock;
/* snapshot.c: */
GENRADIX(struct snapshot_t) snapshots;
struct bch_snapshot_table __rcu *snapshot_table;
struct mutex snapshot_table_lock;
struct work_struct snapshot_delete_work;
/* BTREE CACHE */
struct bio_set btree_bio;
struct workqueue_struct *io_complete_wq;

55
fs/bcachefs/bcachefs_format.h
View File

@ -346,7 +346,9 @@ static inline void bkey_init(struct bkey *k)
x(inline_data, 17) \
x(btree_ptr_v2, 18) \
x(indirect_inline_data, 19) \
x(alloc_v2, 20)
x(alloc_v2, 20) \
x(subvolume, 21) \
x(snapshot, 22)
enum bch_bkey_type {
#define x(name, nr) KEY_TYPE_##name = nr,
@ -690,6 +692,10 @@ struct bch_inode_generation {
__le32 pad;
} __attribute__((packed, aligned(8)));
/*
* bi_subvol and bi_parent_subvol are only set for subvolume roots:
*/
#define BCH_INODE_FIELDS() \
x(bi_atime, 96) \
x(bi_ctime, 96) \
@ -713,7 +719,9 @@ struct bch_inode_generation {
x(bi_erasure_code, 16) \
x(bi_fields_set, 16) \
x(bi_dir, 64) \
x(bi_dir_offset, 64)
x(bi_dir_offset, 64) \
x(bi_subvol, 32) \
x(bi_parent_subvol, 32)
/* subset of BCH_INODE_FIELDS */
#define BCH_INODE_OPTS() \
@ -796,6 +804,9 @@ struct bch_dirent {
__u8 d_name[];
} __attribute__((packed, aligned(8)));
#define DT_SUBVOL 16
#define BCH_DT_MAX 17
#define BCH_NAME_MAX (U8_MAX * sizeof(u64) - \
sizeof(struct bkey) - \
offsetof(struct bch_dirent, d_name))
@ -932,6 +943,42 @@ struct bch_inline_data {
u8 data[0];
};
/* Subvolumes: */
#define SUBVOL_POS_MIN POS(0, 1)
#define SUBVOL_POS_MAX POS(0, S32_MAX)
#define BCACHEFS_ROOT_SUBVOL 1
struct bch_subvolume {
struct bch_val v;
__le32 flags;
__le32 snapshot;
__le64 inode;
};
LE32_BITMASK(BCH_SUBVOLUME_RO, struct bch_subvolume, flags, 0, 1)
/*
* We need to know whether a subvolume is a snapshot so we can know whether we
* can delete it (or whether it should just be rm -rf'd)
*/
LE32_BITMASK(BCH_SUBVOLUME_SNAP, struct bch_subvolume, flags, 1, 2)
/* Snapshots */
struct bch_snapshot {
struct bch_val v;
__le32 flags;
__le32 parent;
__le32 children[2];
__le32 subvol;
__le32 pad;
};
LE32_BITMASK(BCH_SNAPSHOT_DELETED, struct bch_snapshot, flags, 0, 1)
/* True if a subvolume points to this snapshot node: */
LE32_BITMASK(BCH_SNAPSHOT_SUBVOL, struct bch_snapshot, flags, 1, 2)
/* Optional/variable size superblock sections: */
struct bch_sb_field {
@ -1702,7 +1749,9 @@ LE32_BITMASK(JSET_NO_FLUSH, struct jset, flags, 5, 6);
x(alloc, 4) \
x(quotas, 5) \
x(stripes, 6) \
x(reflink, 7)
x(reflink, 7) \
x(subvolumes, 8) \
x(snapshots, 9)
enum btree_id {
#define x(kwd, val) BTREE_ID_##kwd = val,

15
fs/bcachefs/bcachefs_ioctl.h
View File

@ -78,6 +78,9 @@ struct bch_ioctl_incremental {
#define BCH_IOCTL_DISK_RESIZE _IOW(0xbc, 14, struct bch_ioctl_disk_resize)
#define BCH_IOCTL_DISK_RESIZE_JOURNAL _IOW(0xbc,15, struct bch_ioctl_disk_resize_journal)
#define BCH_IOCTL_SUBVOLUME_CREATE _IOW(0xbc, 16, struct bch_ioctl_subvolume)
#define BCH_IOCTL_SUBVOLUME_DESTROY _IOW(0xbc, 17, struct bch_ioctl_subvolume)
/* ioctl below act on a particular file, not the filesystem as a whole: */
#define BCHFS_IOC_REINHERIT_ATTRS _IOR(0xbc, 64, const char __user *)
@ -349,4 +352,16 @@ struct bch_ioctl_disk_resize_journal {
__u64 nbuckets;
};
struct bch_ioctl_subvolume {
__u32 flags;
__u32 dirfd;
__u16 mode;
__u16 pad[3];
__u64 dst_ptr;
__u64 src_ptr;
};
#define BCH_SUBVOL_SNAPSHOT_CREATE (1U << 0)
#define BCH_SUBVOL_SNAPSHOT_RO (1U << 1)
#endif /* _BCACHEFS_IOCTL_H */

5
fs/bcachefs/bkey_methods.c
View File

@ -11,6 +11,7 @@
#include "inode.h"
#include "quota.h"
#include "reflink.h"
#include "subvolume.h"
#include "xattr.h"
const char * const bch2_bkey_types[] = {
@ -126,6 +127,10 @@ static unsigned bch2_key_types_allowed[] = {
[BKEY_TYPE_reflink] =
(1U << KEY_TYPE_reflink_v)|
(1U << KEY_TYPE_indirect_inline_data),
[BKEY_TYPE_subvolumes] =
(1U << KEY_TYPE_subvolume),
[BKEY_TYPE_snapshots] =
(1U << KEY_TYPE_snapshot),
[BKEY_TYPE_btree] =
(1U << KEY_TYPE_btree_ptr)|
(1U << KEY_TYPE_btree_ptr_v2),

5
fs/bcachefs/btree_key_cache.c
View File

@ -164,6 +164,11 @@ btree_key_cache_create(struct btree_key_cache *c,
was_new = false;
}
if (btree_id == BTREE_ID_subvolumes)
six_lock_pcpu_alloc(&ck->c.lock);
else
six_lock_pcpu_free(&ck->c.lock);
ck->c.level = 0;
ck->c.btree_id = btree_id;
ck->key.btree_id = btree_id;

15
fs/bcachefs/btree_types.h
View File

@ -606,7 +606,8 @@ static inline bool btree_node_is_extents(struct btree *b)
#define BTREE_NODE_TYPE_HAS_MEM_TRIGGERS \
((1U << BKEY_TYPE_alloc)| \
(1U << BKEY_TYPE_stripes))
(1U << BKEY_TYPE_stripes)| \
(1U << BKEY_TYPE_snapshots))
#define BTREE_NODE_TYPE_HAS_TRIGGERS \
(BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS| \
@ -653,7 +654,8 @@ enum btree_update_flags {
#define BTREE_TRIGGER_WANTS_OLD_AND_NEW \
((1U << KEY_TYPE_stripe)| \
(1U << KEY_TYPE_inode))
(1U << KEY_TYPE_inode)| \
(1U << KEY_TYPE_snapshot))
static inline bool btree_node_type_needs_gc(enum btree_node_type type)
{
@ -670,11 +672,6 @@ struct btree_root {
s8 error;
};
/*
* Optional hook that will be called just prior to a btree node update, when
* we're holding the write lock and we know what key is about to be overwritten:
*/
enum btree_insert_ret {
BTREE_INSERT_OK,
/* leaf node needs to be split */
@ -695,8 +692,4 @@ enum btree_node_sibling {
btree_next_sib,
};
typedef struct btree_nr_keys (*sort_fix_overlapping_fn)(struct bset *,
struct btree *,
struct btree_node_iter *);
#endif /* _BCACHEFS_BTREE_TYPES_H */

6
fs/bcachefs/btree_update_leaf.c
View File

@ -15,6 +15,7 @@
#include "journal.h"
#include "journal_reclaim.h"
#include "keylist.h"
#include "subvolume.h"
#include "replicas.h"
#include "trace.h"
@ -245,6 +246,11 @@ static inline void btree_insert_entry_checks(struct btree_trans *trans,
BUG_ON(i->cached != i->path->cached);
BUG_ON(i->level != i->path->level);
BUG_ON(i->btree_id != i->path->btree_id);
EBUG_ON(!i->level &&
!(i->flags & BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) &&
test_bit(JOURNAL_REPLAY_DONE, &trans->c->journal.flags) &&
i->k->k.p.snapshot &&
bch2_snapshot_internal_node(trans->c, i->k->k.p.snapshot));
}
static noinline int

3
fs/bcachefs/buckets.c
View File

@ -16,6 +16,7 @@
#include "movinggc.h"
#include "reflink.h"
#include "replicas.h"
#include "subvolume.h"
#include "trace.h"
#include <linux/preempt.h>
@ -1204,6 +1205,8 @@ static int bch2_mark_key_locked(struct bch_fs *c,
return bch2_mark_reservation(c, old, new, journal_seq, flags);
case KEY_TYPE_reflink_p:
return bch2_mark_reflink_p(c, old, new, journal_seq, flags);
case KEY_TYPE_snapshot:
return bch2_mark_snapshot(c, old, new, journal_seq, flags);
default:
return 0;
}

5
fs/bcachefs/dirent.c
View File

@ -99,7 +99,8 @@ const char *bch2_dirent_invalid(const struct bch_fs *c, struct bkey_s_c k)
if (memchr(d.v->d_name, '/', len))
return "invalid name";
if (le64_to_cpu(d.v->d_inum) == d.k->p.inode)
if (d.v->d_type != DT_SUBVOL &&
le64_to_cpu(d.v->d_inum) == d.k->p.inode)
return "dirent points to own directory";
return NULL;
@ -113,7 +114,7 @@ void bch2_dirent_to_text(struct printbuf *out, struct bch_fs *c,
bch_scnmemcpy(out, d.v->d_name,
bch2_dirent_name_bytes(d));
pr_buf(out, " -> %llu type %s", d.v->d_inum,
d.v->d_type < DT_MAX
d.v->d_type < BCH_DT_MAX
? bch2_d_types[d.v->d_type]
: "(bad d_type)");
}

4
fs/bcachefs/fsck.c
View File

@ -9,6 +9,7 @@
#include "fsck.h"
#include "inode.h"
#include "keylist.h"
#include "subvolume.h"
#include "super.h"
#include "xattr.h"
@ -1410,7 +1411,8 @@ int bch2_fsck_full(struct bch_fs *c)
{
struct bch_inode_unpacked root_inode;
return check_inodes(c, true) ?:
return bch2_fs_snapshots_check(c) ?:
check_inodes(c, true) ?:
check_extents(c) ?:
check_dirents(c) ?:
check_xattrs(c) ?:

11
fs/bcachefs/inode.c
View File

@ -8,6 +8,7 @@
#include "extents.h"
#include "inode.h"
#include "str_hash.h"
#include "subvolume.h"
#include "varint.h"
#include <linux/random.h>
@ -368,6 +369,9 @@ const char *bch2_inode_invalid(const struct bch_fs *c, struct bkey_s_c k)
unpacked.bi_nlink != 0)
return "flagged as unlinked but bi_nlink != 0";
if (unpacked.bi_subvol && !S_ISDIR(unpacked.bi_mode))
return "subvolume root but not a directory";
return NULL;
}
@ -635,6 +639,13 @@ retry:
bch2_inode_unpack(bkey_s_c_to_inode(k), &inode_u);
/* Subvolume root? */
if (inode_u.bi_subvol) {
ret = bch2_subvolume_delete(&trans, inode_u.bi_subvol, -1);
if (ret)
goto err;
}
bkey_inode_generation_init(&delete.k_i);
delete.k.p = iter.pos;
delete.v.bi_generation = cpu_to_le32(inode_u.bi_generation + 1);

3
fs/bcachefs/opts.c
View File

@ -63,7 +63,7 @@ const char * const bch2_member_states[] = {
#undef x
const char * const bch2_d_types[DT_MAX] = {
const char * const bch2_d_types[BCH_DT_MAX] = {
[DT_UNKNOWN] = "unknown",
[DT_FIFO] = "fifo",
[DT_CHR] = "chr",
@ -73,6 +73,7 @@ const char * const bch2_d_types[DT_MAX] = {
[DT_LNK] = "lnk",
[DT_SOCK] = "sock",
[DT_WHT] = "whiteout",
[DT_SUBVOL] = "subvol",
};
void bch2_opts_apply(struct bch_opts *dst, struct bch_opts src)

119
fs/bcachefs/recovery.c
View File

@ -20,6 +20,7 @@
#include "quota.h"
#include "recovery.h"
#include "replicas.h"
#include "subvolume.h"
#include "super-io.h"
#include <linux/sort.h>
@ -961,6 +962,81 @@ fsck_err:
return ret;
}
static int bch2_fs_initialize_subvolumes(struct bch_fs *c)
{
struct bkey_i_snapshot root_snapshot;
struct bkey_i_subvolume root_volume;
int ret;
bkey_snapshot_init(&root_snapshot.k_i);
root_snapshot.k.p.offset = U32_MAX;
root_snapshot.v.flags = 0;
root_snapshot.v.parent = 0;
root_snapshot.v.subvol = BCACHEFS_ROOT_SUBVOL;
root_snapshot.v.pad = 0;
SET_BCH_SNAPSHOT_SUBVOL(&root_snapshot.v, true);
ret = bch2_btree_insert(c, BTREE_ID_snapshots,
&root_snapshot.k_i,
NULL, NULL, 0);
if (ret)
return ret;
bkey_subvolume_init(&root_volume.k_i);
root_volume.k.p.offset = BCACHEFS_ROOT_SUBVOL;
root_volume.v.flags = 0;
root_volume.v.snapshot = cpu_to_le32(U32_MAX);
root_volume.v.inode = cpu_to_le64(BCACHEFS_ROOT_INO);
ret = bch2_btree_insert(c, BTREE_ID_subvolumes,
&root_volume.k_i,
NULL, NULL, 0);
if (ret)
return ret;
return 0;
}
static int bch2_fs_upgrade_for_subvolumes(struct btree_trans *trans)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct bkey_s_c k;
struct bch_inode_unpacked inode;
struct bkey_inode_buf *packed;
int ret;
bch2_trans_iter_init(trans, &iter, BTREE_ID_inodes,
POS(0, BCACHEFS_ROOT_INO), 0);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_inode) {
bch_err(c, "root inode not found");
ret = -ENOENT;
goto err;
}
ret = bch2_inode_unpack(bkey_s_c_to_inode(k), &inode);
BUG_ON(ret);
inode.bi_subvol = BCACHEFS_ROOT_SUBVOL;
packed = bch2_trans_kmalloc(trans, sizeof(*packed));
ret = PTR_ERR_OR_ZERO(packed);
if (ret)
goto err;
bch2_inode_pack(c, packed, &inode);
ret = bch2_trans_update(trans, &iter, &packed->inode.k_i, 0);
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
int bch2_fs_recovery(struct bch_fs *c)
{
const char *err = "cannot allocate memory";
@ -1017,11 +1093,12 @@ int bch2_fs_recovery(struct bch_fs *c)
c->opts.version_upgrade = true;
c->opts.fsck = true;
c->opts.fix_errors = FSCK_OPT_YES;
}
if (c->sb.version < bcachefs_metadata_version_btree_ptr_sectors_written) {
} else if (c->sb.version < bcachefs_metadata_version_btree_ptr_sectors_written) {
bch_info(c, "version prior to btree_ptr_sectors_written, upgrade required");
c->opts.version_upgrade = true;
} else if (c->sb.version < bcachefs_metadata_version_snapshot) {
bch_info(c, "filesystem version is prior to snapshot field - upgrading");
c->opts.version_upgrade = true;
}
ret = bch2_blacklist_table_initialize(c);
@ -1190,6 +1267,29 @@ use_clean:
bch_verbose(c, "alloc write done");
}
if (c->sb.version < bcachefs_metadata_version_snapshot) {
err = "error creating root snapshot node";
ret = bch2_fs_initialize_subvolumes(c);
if (ret)
goto err;
}
bch_verbose(c, "reading snapshots table");
err = "error reading snapshots table";
ret = bch2_fs_snapshots_start(c);
if (ret)
goto err;
bch_verbose(c, "reading snapshots done");
if (c->sb.version < bcachefs_metadata_version_snapshot) {
/* set bi_subvol on root inode */
err = "error upgrade root inode for subvolumes";
ret = bch2_trans_do(c, NULL, NULL, BTREE_INSERT_LAZY_RW,
bch2_fs_upgrade_for_subvolumes(&trans));
if (ret)
goto err;
}
if (c->opts.fsck) {
bch_info(c, "starting fsck");
err = "error in fsck";
@ -1350,9 +1450,22 @@ int bch2_fs_initialize(struct bch_fs *c)
}
}
err = "error creating root snapshot node";
ret = bch2_fs_initialize_subvolumes(c);
if (ret)
goto err;
bch_verbose(c, "reading snapshots table");
err = "error reading snapshots table";
ret = bch2_fs_snapshots_start(c);
if (ret)
goto err;
bch_verbose(c, "reading snapshots done");
bch2_inode_init(c, &root_inode, 0, 0,
S_IFDIR|S_IRWXU|S_IRUGO|S_IXUGO, 0, NULL);
root_inode.bi_inum = BCACHEFS_ROOT_INO;
root_inode.bi_subvol = BCACHEFS_ROOT_SUBVOL;
bch2_inode_pack(c, &packed_inode, &root_inode);
packed_inode.inode.k.p.snapshot = U32_MAX;

981
fs/bcachefs/subvolume.c Normal file
View File

@ -0,0 +1,981 @@
// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "btree_key_cache.h"
#include "btree_update.h"
#include "error.h"
#include "subvolume.h"
/* Snapshot tree: */
static void bch2_delete_dead_snapshots_work(struct work_struct *);
static void bch2_delete_dead_snapshots(struct bch_fs *);
void bch2_snapshot_to_text(struct printbuf *out, struct bch_fs *c,
struct bkey_s_c k)
{
struct bkey_s_c_snapshot s = bkey_s_c_to_snapshot(k);
pr_buf(out, "is_subvol %llu deleted %llu parent %u children %u %u subvol %u",
BCH_SNAPSHOT_SUBVOL(s.v),
BCH_SNAPSHOT_DELETED(s.v),
le32_to_cpu(s.v->parent),
le32_to_cpu(s.v->children[0]),
le32_to_cpu(s.v->children[1]),
le32_to_cpu(s.v->subvol));
}
const char *bch2_snapshot_invalid(const struct bch_fs *c, struct bkey_s_c k)
{
struct bkey_s_c_snapshot s;
u32 i, id;
if (bkey_cmp(k.k->p, POS(0, U32_MAX)) > 0 ||
bkey_cmp(k.k->p, POS(0, 1)) < 0)
return "bad pos";
if (bkey_val_bytes(k.k) != sizeof(struct bch_snapshot))
return "bad val size";
s = bkey_s_c_to_snapshot(k);
id = le32_to_cpu(s.v->parent);
if (id && id <= k.k->p.offset)
return "bad parent node";
if (le32_to_cpu(s.v->children[0]) < le32_to_cpu(s.v->children[1]))
return "children not normalized";
if (s.v->children[0] &&
s.v->children[0] == s.v->children[1])
return "duplicate child nodes";
for (i = 0; i < 2; i++) {
id = le32_to_cpu(s.v->children[i]);
if (id >= k.k->p.offset)
return "bad child node";
}
return NULL;
}
int bch2_mark_snapshot(struct bch_fs *c,
struct bkey_s_c old, struct bkey_s_c new,
u64 journal_seq, unsigned flags)
{
struct snapshot_t *t;
t = genradix_ptr_alloc(&c->snapshots,
U32_MAX - new.k->p.offset,
GFP_KERNEL);
if (!t)
return -ENOMEM;
if (new.k->type == KEY_TYPE_snapshot) {
struct bkey_s_c_snapshot s = bkey_s_c_to_snapshot(new);
t->parent = le32_to_cpu(s.v->parent);
t->children[0] = le32_to_cpu(s.v->children[0]);
t->children[1] = le32_to_cpu(s.v->children[1]);
t->subvol = BCH_SNAPSHOT_SUBVOL(s.v) ? le32_to_cpu(s.v->subvol) : 0;
} else {
t->parent = 0;
t->children[0] = 0;
t->children[1] = 0;
t->subvol = 0;
}
return 0;
}
static int subvol_lookup(struct btree_trans *trans, unsigned id, struct bch_subvolume *s)
{
struct btree_iter iter;
struct bkey_s_c k;
int ret;
bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes, POS(0, id), 0);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k) ?: k.k->type == KEY_TYPE_subvolume ? 0 : -ENOENT;
if (!ret)
*s = *bkey_s_c_to_subvolume(k).v;
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static int snapshot_lookup(struct btree_trans *trans, u32 id,
struct bch_snapshot *s)
{
struct btree_iter iter;
struct bkey_s_c k;
int ret;
bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id),
BTREE_ITER_WITH_UPDATES);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k) ?: k.k->type == KEY_TYPE_snapshot ? 0 : -ENOENT;
if (!ret)
*s = *bkey_s_c_to_snapshot(k).v;
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static int snapshot_live(struct btree_trans *trans, u32 id)
{
struct bch_snapshot v;
int ret;
if (!id)
return 0;
ret = lockrestart_do(trans, snapshot_lookup(trans, id, &v));
if (ret == -ENOENT)
bch_err(trans->c, "snapshot node %u not found", id);
if (ret)
return ret;
return !BCH_SNAPSHOT_DELETED(&v);
}
static int bch2_snapshots_set_equiv(struct btree_trans *trans)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct bkey_s_c k;
struct bkey_s_c_snapshot snap;
unsigned i;
int ret;
for_each_btree_key(trans, iter, BTREE_ID_snapshots,
POS_MIN, 0, k, ret) {
u32 id = k.k->p.offset, child[2];
unsigned nr_live = 0, live_idx;
if (k.k->type != KEY_TYPE_snapshot)
continue;
snap = bkey_s_c_to_snapshot(k);
child[0] = le32_to_cpu(snap.v->children[0]);
child[1] = le32_to_cpu(snap.v->children[1]);
for (i = 0; i < 2; i++) {
ret = snapshot_live(trans, child[i]);
if (ret < 0)
break;
if (ret)
live_idx = i;
nr_live += ret;
}
snapshot_t(c, id)->equiv = nr_live == 1
? snapshot_t(c, child[live_idx])->equiv
: id;
}
bch2_trans_iter_exit(trans, &iter);
if (ret)
bch_err(c, "error walking snapshots: %i", ret);
return ret;
}
/* fsck: */
static int bch2_snapshot_check(struct btree_trans *trans,
struct bkey_s_c_snapshot s)
{
struct bch_subvolume subvol;
struct bch_snapshot v;
u32 i, id;
int ret;
id = le32_to_cpu(s.v->subvol);
ret = lockrestart_do(trans, subvol_lookup(trans, id, &subvol));
if (ret == -ENOENT)
bch_err(trans->c, "snapshot node %llu has nonexistent subvolume %u",
s.k->p.offset, id);
if (ret)
return ret;
if (BCH_SNAPSHOT_SUBVOL(s.v) != (le32_to_cpu(subvol.snapshot) == s.k->p.offset)) {
bch_err(trans->c, "snapshot node %llu has wrong BCH_SNAPSHOT_SUBVOL",
s.k->p.offset);
return -EINVAL;
}
id = le32_to_cpu(s.v->parent);
if (id) {
ret = lockrestart_do(trans, snapshot_lookup(trans, id, &v));
if (ret == -ENOENT)
bch_err(trans->c, "snapshot node %llu has nonexistent parent %u",
s.k->p.offset, id);
if (ret)
return ret;
if (le32_to_cpu(v.children[0]) != s.k->p.offset &&
le32_to_cpu(v.children[1]) != s.k->p.offset) {
bch_err(trans->c, "snapshot parent %u missing pointer to child %llu",
id, s.k->p.offset);
return -EINVAL;
}
}
for (i = 0; i < 2 && s.v->children[i]; i++) {
id = le32_to_cpu(s.v->children[i]);
ret = lockrestart_do(trans, snapshot_lookup(trans, id, &v));
if (ret == -ENOENT)
bch_err(trans->c, "snapshot node %llu has nonexistent child %u",
s.k->p.offset, id);
if (ret)
return ret;
if (le32_to_cpu(v.parent) != s.k->p.offset) {
bch_err(trans->c, "snapshot child %u has wrong parent (got %u should be %llu)",
id, le32_to_cpu(v.parent), s.k->p.offset);
return -EINVAL;
}
}
return 0;
}
int bch2_fs_snapshots_check(struct bch_fs *c)
{
struct btree_trans trans;
struct btree_iter iter;
struct bkey_s_c k;
struct bch_snapshot s;
unsigned id;
int ret;
bch2_trans_init(&trans, c, 0, 0);
for_each_btree_key(&trans, iter, BTREE_ID_snapshots,
POS_MIN, 0, k, ret) {
if (k.k->type != KEY_TYPE_snapshot)
continue;
ret = bch2_snapshot_check(&trans, bkey_s_c_to_snapshot(k));
if (ret)
break;
}
bch2_trans_iter_exit(&trans, &iter);
if (ret) {
bch_err(c, "error %i checking snapshots", ret);
goto err;
}
for_each_btree_key(&trans, iter, BTREE_ID_subvolumes,
POS_MIN, 0, k, ret) {
if (k.k->type != KEY_TYPE_subvolume)
continue;
again_2:
id = le32_to_cpu(bkey_s_c_to_subvolume(k).v->snapshot);
ret = snapshot_lookup(&trans, id, &s);
if (ret == -EINTR) {
k = bch2_btree_iter_peek(&iter);
goto again_2;
} else if (ret == -ENOENT)
bch_err(c, "subvolume %llu points to nonexistent snapshot %u",
k.k->p.offset, id);
else if (ret)
break;
}
bch2_trans_iter_exit(&trans, &iter);
err:
bch2_trans_exit(&trans);
return ret;
}
void bch2_fs_snapshots_exit(struct bch_fs *c)
{
genradix_free(&c->snapshots);
}
int bch2_fs_snapshots_start(struct bch_fs *c)
{
struct btree_trans trans;
struct btree_iter iter;
struct bkey_s_c k;
bool have_deleted = false;
int ret = 0;
bch2_trans_init(&trans, c, 0, 0);
for_each_btree_key(&trans, iter, BTREE_ID_snapshots,
POS_MIN, 0, k, ret) {
if (bkey_cmp(k.k->p, POS(0, U32_MAX)) > 0)
break;
if (k.k->type != KEY_TYPE_snapshot) {
bch_err(c, "found wrong key type %u in snapshot node table",
k.k->type);
continue;
}
if (BCH_SNAPSHOT_DELETED(bkey_s_c_to_snapshot(k).v))
have_deleted = true;
ret = bch2_mark_snapshot(c, bkey_s_c_null, k, 0, 0);
if (ret)
break;
}
bch2_trans_iter_exit(&trans, &iter);
if (ret)
goto err;
ret = bch2_snapshots_set_equiv(&trans);
if (ret)
goto err;
err:
bch2_trans_exit(&trans);
if (!ret && have_deleted) {
bch_info(c, "restarting deletion of dead snapshots");
if (c->opts.fsck) {
bch2_delete_dead_snapshots_work(&c->snapshot_delete_work);
} else {
bch2_delete_dead_snapshots(c);
}
}
return ret;
}
/*
* Mark a snapshot as deleted, for future cleanup:
*/
static int bch2_snapshot_node_set_deleted(struct btree_trans *trans, u32 id)
{
struct btree_iter iter;
struct bkey_s_c k;
struct bkey_i_snapshot *s;
int ret = 0;
bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id),
BTREE_ITER_INTENT);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_snapshot) {
bch2_fs_inconsistent(trans->c, "missing snapshot %u", id);
ret = -ENOENT;
goto err;
}
/* already deleted? */
if (BCH_SNAPSHOT_DELETED(bkey_s_c_to_snapshot(k).v))
goto err;
s = bch2_trans_kmalloc(trans, sizeof(*s));
ret = PTR_ERR_OR_ZERO(s);
if (ret)
goto err;
bkey_reassemble(&s->k_i, k);
SET_BCH_SNAPSHOT_DELETED(&s->v, true);
ret = bch2_trans_update(trans, &iter, &s->k_i, 0);
if (ret)
goto err;
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static int bch2_snapshot_node_delete(struct btree_trans *trans, u32 id)
{
struct btree_iter iter, p_iter = (struct btree_iter) { NULL };
struct bkey_s_c k;
struct bkey_s_c_snapshot s;
struct bkey_i_snapshot *parent;
u32 parent_id;
unsigned i;
int ret = 0;
bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots, POS(0, id),
BTREE_ITER_INTENT);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_snapshot) {
bch2_fs_inconsistent(trans->c, "missing snapshot %u", id);
ret = -ENOENT;
goto err;
}
s = bkey_s_c_to_snapshot(k);
BUG_ON(!BCH_SNAPSHOT_DELETED(s.v));
parent_id = le32_to_cpu(s.v->parent);
if (parent_id) {
bch2_trans_iter_init(trans, &p_iter, BTREE_ID_snapshots,
POS(0, parent_id),
BTREE_ITER_INTENT);
k = bch2_btree_iter_peek_slot(&p_iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_snapshot) {
bch2_fs_inconsistent(trans->c, "missing snapshot %u", parent_id);
ret = -ENOENT;
goto err;
}
parent = bch2_trans_kmalloc(trans, sizeof(*parent));
ret = PTR_ERR_OR_ZERO(parent);
if (ret)
goto err;
bkey_reassemble(&parent->k_i, k);
for (i = 0; i < 2; i++)
if (le32_to_cpu(parent->v.children[i]) == id)
break;
if (i == 2)
bch_err(trans->c, "snapshot %u missing child pointer to %u",
parent_id, id);
else
parent->v.children[i] = 0;
if (le32_to_cpu(parent->v.children[0]) <
le32_to_cpu(parent->v.children[1]))
swap(parent->v.children[0],
parent->v.children[1]);
ret = bch2_trans_update(trans, &p_iter, &parent->k_i, 0);
if (ret)
goto err;
}
ret = bch2_btree_delete_at(trans, &iter, 0);
err:
bch2_trans_iter_exit(trans, &p_iter);
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static int bch2_snapshot_node_create(struct btree_trans *trans, u32 parent,
u32 *new_snapids,
u32 *snapshot_subvols,
unsigned nr_snapids)
{
struct btree_iter iter;
struct bkey_i_snapshot *n;
struct bkey_s_c k;
unsigned i;
int ret = 0;
bch2_trans_iter_init(trans, &iter, BTREE_ID_snapshots,
POS_MIN, BTREE_ITER_INTENT);
k = bch2_btree_iter_peek(&iter);
ret = bkey_err(k);
if (ret)
goto err;
for (i = 0; i < nr_snapids; i++) {
k = bch2_btree_iter_prev_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (!k.k || !k.k->p.offset) {
ret = -ENOSPC;
goto err;
}
n = bch2_trans_kmalloc(trans, sizeof(*n));
ret = PTR_ERR_OR_ZERO(n);
if (ret)
return ret;
bkey_snapshot_init(&n->k_i);
n->k.p = iter.pos;
n->v.flags = 0;
n->v.parent = cpu_to_le32(parent);
n->v.subvol = cpu_to_le32(snapshot_subvols[i]);
n->v.pad = 0;
SET_BCH_SNAPSHOT_SUBVOL(&n->v, true);
bch2_trans_update(trans, &iter, &n->k_i, 0);
ret = bch2_mark_snapshot(trans->c, bkey_s_c_null, bkey_i_to_s_c(&n->k_i), 0, 0);
if (ret)
break;
new_snapids[i] = iter.pos.offset;
}
if (parent) {
bch2_btree_iter_set_pos(&iter, POS(0, parent));
k = bch2_btree_iter_peek(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_snapshot) {
bch_err(trans->c, "snapshot %u not found", parent);
ret = -ENOENT;
goto err;
}
n = bch2_trans_kmalloc(trans, sizeof(*n));
ret = PTR_ERR_OR_ZERO(n);
if (ret)
return ret;
bkey_reassemble(&n->k_i, k);
if (n->v.children[0] || n->v.children[1]) {
bch_err(trans->c, "Trying to add child snapshot nodes to parent that already has children");
ret = -EINVAL;
goto err;
}
n->v.children[0] = cpu_to_le32(new_snapids[0]);
n->v.children[1] = cpu_to_le32(new_snapids[1]);
SET_BCH_SNAPSHOT_SUBVOL(&n->v, false);
bch2_trans_update(trans, &iter, &n->k_i, 0);
}
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
/* List of snapshot IDs that are being deleted: */
struct snapshot_id_list {
u32 nr;
u32 size;
u32 *d;
};
static bool snapshot_list_has_id(struct snapshot_id_list *s, u32 id)
{
unsigned i;
for (i = 0; i < s->nr; i++)
if (id == s->d[i])
return true;
return false;
}
static int snapshot_id_add(struct snapshot_id_list *s, u32 id)
{
BUG_ON(snapshot_list_has_id(s, id));
if (s->nr == s->size) {
size_t new_size = max(8U, s->size * 2);
void *n = krealloc(s->d,
new_size * sizeof(s->d[0]),
GFP_KERNEL);
if (!n) {
pr_err("error allocating snapshot ID list");
return -ENOMEM;
}
s->d = n;
s->size = new_size;
};
s->d[s->nr++] = id;
return 0;
}
static int bch2_snapshot_delete_keys_btree(struct btree_trans *trans,
struct snapshot_id_list *deleted,
enum btree_id btree_id)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct bkey_s_c k;
struct snapshot_id_list equiv_seen = { 0 };
struct bpos last_pos = POS_MIN;
int ret = 0;
/*
* XXX: We should also delete whiteouts that no longer overwrite
* anything
*/
bch2_trans_iter_init(trans, &iter, btree_id, POS_MIN,
BTREE_ITER_INTENT|
BTREE_ITER_PREFETCH|
BTREE_ITER_NOT_EXTENTS|
BTREE_ITER_ALL_SNAPSHOTS);
while ((bch2_trans_begin(trans),
(k = bch2_btree_iter_peek(&iter)).k) &&
!(ret = bkey_err(k))) {
u32 equiv = snapshot_t(c, k.k->p.snapshot)->equiv;
if (bkey_cmp(k.k->p, last_pos))
equiv_seen.nr = 0;
last_pos = k.k->p;
if (snapshot_list_has_id(deleted, k.k->p.snapshot) ||
snapshot_list_has_id(&equiv_seen, equiv)) {
if (btree_id == BTREE_ID_inodes &&
bch2_btree_key_cache_flush(trans, btree_id, iter.pos))
continue;
ret = __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL,
bch2_btree_iter_traverse(&iter) ?:
bch2_btree_delete_at(trans, &iter,
BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE));
if (ret)
break;
} else {
ret = snapshot_id_add(&equiv_seen, equiv);
if (ret)
break;
}
bch2_btree_iter_advance(&iter);
}
bch2_trans_iter_exit(trans, &iter);
kfree(equiv_seen.d);
return ret;
}
static void bch2_delete_dead_snapshots_work(struct work_struct *work)
{
struct bch_fs *c = container_of(work, struct bch_fs, snapshot_delete_work);
struct btree_trans trans;
struct btree_iter iter;
struct bkey_s_c k;
struct bkey_s_c_snapshot snap;
struct snapshot_id_list deleted = { 0 };
u32 i, id, children[2];
int ret = 0;
bch2_trans_init(&trans, c, 0, 0);
/*
* For every snapshot node: If we have no live children and it's not
* pointed to by a subvolume, delete it:
*/
for_each_btree_key(&trans, iter, BTREE_ID_snapshots,
POS_MIN, 0, k, ret) {
if (k.k->type != KEY_TYPE_snapshot)
continue;
snap = bkey_s_c_to_snapshot(k);
if (BCH_SNAPSHOT_DELETED(snap.v) ||
BCH_SNAPSHOT_SUBVOL(snap.v))
continue;
children[0] = le32_to_cpu(snap.v->children[0]);
children[1] = le32_to_cpu(snap.v->children[1]);
ret = snapshot_live(&trans, children[0]) ?:
snapshot_live(&trans, children[1]);
if (ret < 0)
break;
if (ret)
continue;
ret = __bch2_trans_do(&trans, NULL, NULL, 0,
bch2_snapshot_node_set_deleted(&trans, iter.pos.offset));
if (ret) {
bch_err(c, "error deleting snapshot %llu: %i", iter.pos.offset, ret);
break;
}
}
bch2_trans_iter_exit(&trans, &iter);
if (ret) {
bch_err(c, "error walking snapshots: %i", ret);
goto err;
}
ret = bch2_snapshots_set_equiv(&trans);
if (ret)
goto err;
for_each_btree_key(&trans, iter, BTREE_ID_snapshots,
POS_MIN, 0, k, ret) {
if (k.k->type != KEY_TYPE_snapshot)
continue;
snap = bkey_s_c_to_snapshot(k);
if (BCH_SNAPSHOT_DELETED(snap.v)) {
ret = snapshot_id_add(&deleted, k.k->p.offset);
if (ret)
break;
}
}
bch2_trans_iter_exit(&trans, &iter);
if (ret) {
bch_err(c, "error walking snapshots: %i", ret);
goto err;
}
for (id = 0; id < BTREE_ID_NR; id++) {
if (!btree_type_has_snapshots(id))
continue;
ret = bch2_snapshot_delete_keys_btree(&trans, &deleted, id);
if (ret) {
bch_err(c, "error deleting snapshot keys: %i", ret);
goto err;
}
}
for (i = 0; i < deleted.nr; i++) {
ret = __bch2_trans_do(&trans, NULL, NULL, 0,
bch2_snapshot_node_delete(&trans, deleted.d[i]));
if (ret) {
bch_err(c, "error deleting snapshot %u: %i",
deleted.d[i], ret);
goto err;
}
}
err:
kfree(deleted.d);
bch2_trans_exit(&trans);
percpu_ref_put(&c->writes);
}
static void bch2_delete_dead_snapshots(struct bch_fs *c)
{
if (unlikely(!percpu_ref_tryget(&c->writes)))
return;
if (!queue_work(system_long_wq, &c->snapshot_delete_work))
percpu_ref_put(&c->writes);
}
static int bch2_delete_dead_snapshots_hook(struct btree_trans *trans,
struct btree_trans_commit_hook *h)
{
bch2_delete_dead_snapshots(trans->c);
return 0;
}
/* Subvolumes: */
const char *bch2_subvolume_invalid(const struct bch_fs *c, struct bkey_s_c k)
{
if (bkey_cmp(k.k->p, SUBVOL_POS_MIN) < 0)
return "invalid pos";
if (bkey_cmp(k.k->p, SUBVOL_POS_MAX) > 0)
return "invalid pos";
if (bkey_val_bytes(k.k) != sizeof(struct bch_subvolume))
return "bad val size";
return NULL;
}
void bch2_subvolume_to_text(struct printbuf *out, struct bch_fs *c,
struct bkey_s_c k)
{
struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k);
pr_buf(out, "root %llu snapshot id %u",
le64_to_cpu(s.v->inode),
le32_to_cpu(s.v->snapshot));
}
int bch2_subvolume_get_snapshot(struct btree_trans *trans, u32 subvol,
u32 *snapid)
{
struct btree_iter iter;
struct bkey_s_c k;
int ret;
bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes,
POS(0, subvol),
BTREE_ITER_CACHED|
BTREE_ITER_WITH_UPDATES);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_subvolume) {
bch2_fs_inconsistent(trans->c, "missing subvolume %u", subvol);
ret = -EIO;
goto err;
}
*snapid = le32_to_cpu(bkey_s_c_to_subvolume(k).v->snapshot);
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
/* XXX: mark snapshot id for deletion, walk btree and delete: */
int bch2_subvolume_delete(struct btree_trans *trans, u32 subvolid,
int deleting_snapshot)
{
struct btree_iter iter;
struct bkey_s_c k;
struct bkey_s_c_subvolume subvol;
struct btree_trans_commit_hook *h;
struct bkey_i *delete;
u32 snapid;
int ret = 0;
bch2_trans_iter_init(trans, &iter, BTREE_ID_subvolumes,
POS(0, subvolid),
BTREE_ITER_CACHED|
BTREE_ITER_INTENT);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_subvolume) {
bch2_fs_inconsistent(trans->c, "missing subvolume %u", subvolid);
ret = -EIO;
goto err;
}
subvol = bkey_s_c_to_subvolume(k);
snapid = le32_to_cpu(subvol.v->snapshot);
if (deleting_snapshot >= 0 &&
deleting_snapshot != BCH_SUBVOLUME_SNAP(subvol.v)) {
ret = -ENOENT;
goto err;
}
delete = bch2_trans_kmalloc(trans, sizeof(*delete));
ret = PTR_ERR_OR_ZERO(delete);
if (ret)
goto err;
bkey_init(&delete->k);
delete->k.p = iter.pos;
ret = bch2_trans_update(trans, &iter, delete, 0);
if (ret)
goto err;
ret = bch2_snapshot_node_set_deleted(trans, snapid);
h = bch2_trans_kmalloc(trans, sizeof(*h));
ret = PTR_ERR_OR_ZERO(h);
if (ret)
goto err;
h->fn = bch2_delete_dead_snapshots_hook;
bch2_trans_commit_hook(trans, h);
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
int bch2_subvolume_create(struct btree_trans *trans, u64 inode,
u32 src_subvolid,
u32 *new_subvolid,
u32 *new_snapshotid,
bool ro)
{
struct btree_iter dst_iter, src_iter = (struct btree_iter) { NULL };
struct bkey_i_subvolume *new_subvol = NULL;
struct bkey_i_subvolume *src_subvol = NULL;
struct bkey_s_c k;
u32 parent = 0, new_nodes[2], snapshot_subvols[2];
int ret = 0;
for_each_btree_key(trans, dst_iter, BTREE_ID_subvolumes, SUBVOL_POS_MIN,
BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) {
if (bkey_cmp(k.k->p, SUBVOL_POS_MAX) > 0)
break;
if (bkey_deleted(k.k))
goto found_slot;
}
if (!ret)
ret = -ENOSPC;
goto err;
found_slot:
snapshot_subvols[0] = dst_iter.pos.offset;
snapshot_subvols[1] = src_subvolid;
if (src_subvolid) {
/* Creating a snapshot: */
src_subvol = bch2_trans_kmalloc(trans, sizeof(*src_subvol));
ret = PTR_ERR_OR_ZERO(src_subvol);
if (ret)
goto err;
bch2_trans_iter_init(trans, &src_iter, BTREE_ID_subvolumes,
POS(0, src_subvolid),
BTREE_ITER_CACHED|
BTREE_ITER_INTENT);
k = bch2_btree_iter_peek_slot(&src_iter);
ret = bkey_err(k);
if (ret)
goto err;
if (k.k->type != KEY_TYPE_subvolume) {
bch_err(trans->c, "subvolume %u not found", src_subvolid);
ret = -ENOENT;
goto err;
}
bkey_reassemble(&src_subvol->k_i, k);
parent = le32_to_cpu(src_subvol->v.snapshot);
}
ret = bch2_snapshot_node_create(trans, parent, new_nodes,
snapshot_subvols,
src_subvolid ? 2 : 1);
if (ret)
goto err;
if (src_subvolid) {
src_subvol->v.snapshot = cpu_to_le32(new_nodes[1]);
bch2_trans_update(trans, &src_iter, &src_subvol->k_i, 0);
}
new_subvol = bch2_trans_kmalloc(trans, sizeof(*new_subvol));
ret = PTR_ERR_OR_ZERO(new_subvol);
if (ret)
goto err;
bkey_subvolume_init(&new_subvol->k_i);
new_subvol->v.flags = 0;
new_subvol->v.snapshot = cpu_to_le32(new_nodes[0]);
new_subvol->v.inode = cpu_to_le64(inode);
SET_BCH_SUBVOLUME_RO(&new_subvol->v, ro);
SET_BCH_SUBVOLUME_SNAP(&new_subvol->v, src_subvolid != 0);
new_subvol->k.p = dst_iter.pos;
bch2_trans_update(trans, &dst_iter, &new_subvol->k_i, 0);
*new_subvolid = new_subvol->k.p.offset;
*new_snapshotid = new_nodes[0];
err:
bch2_trans_iter_exit(trans, &src_iter);
bch2_trans_iter_exit(trans, &dst_iter);
return ret;
}
int bch2_fs_subvolumes_init(struct bch_fs *c)
{
INIT_WORK(&c->snapshot_delete_work, bch2_delete_dead_snapshots_work);
return 0;
}

77
fs/bcachefs/subvolume.h Normal file
View File

@ -0,0 +1,77 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_SUBVOLUME_H
#define _BCACHEFS_SUBVOLUME_H
void bch2_snapshot_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
const char *bch2_snapshot_invalid(const struct bch_fs *, struct bkey_s_c);
#define bch2_bkey_ops_snapshot (struct bkey_ops) { \
.key_invalid = bch2_snapshot_invalid, \
.val_to_text = bch2_snapshot_to_text, \
}
int bch2_mark_snapshot(struct bch_fs *, struct bkey_s_c,
struct bkey_s_c, u64, unsigned);
static inline struct snapshot_t *snapshot_t(struct bch_fs *c, u32 id)
{
return genradix_ptr(&c->snapshots, U32_MAX - id);
}
static inline u32 bch2_snapshot_parent(struct bch_fs *c, u32 id)
{
return snapshot_t(c, id)->parent;
}
static inline u32 bch2_snapshot_internal_node(struct bch_fs *c, u32 id)
{
struct snapshot_t *s = snapshot_t(c, id);
return s->children[0] || s->children[1];
}
static inline u32 bch2_snapshot_sibling(struct bch_fs *c, u32 id)
{
struct snapshot_t *s;
u32 parent = bch2_snapshot_parent(c, id);
if (!parent)
return 0;
s = snapshot_t(c, bch2_snapshot_parent(c, id));
if (id == s->children[0])
return s->children[1];
if (id == s->children[1])
return s->children[0];
return 0;
}
static inline bool bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor)
{
while (id && id < ancestor)
id = bch2_snapshot_parent(c, id);
return id == ancestor;
}
int bch2_fs_snapshots_check(struct bch_fs *);
void bch2_fs_snapshots_exit(struct bch_fs *);
int bch2_fs_snapshots_start(struct bch_fs *);
const char *bch2_subvolume_invalid(const struct bch_fs *, struct bkey_s_c);
void bch2_subvolume_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
#define bch2_bkey_ops_subvolume (struct bkey_ops) { \
.key_invalid = bch2_subvolume_invalid, \
.val_to_text = bch2_subvolume_to_text, \
}
int bch2_subvolume_get_snapshot(struct btree_trans *, u32, u32 *);
int bch2_subvolume_delete(struct btree_trans *, u32, int);
int bch2_subvolume_create(struct btree_trans *, u64, u32,
u32 *, u32 *, bool);
int bch2_fs_subvolumes_init(struct bch_fs *);
#endif /* _BCACHEFS_SUBVOLUME_H */

4
fs/bcachefs/super.c
View File

@ -39,6 +39,7 @@
#include "rebalance.h"
#include "recovery.h"
#include "replicas.h"
#include "subvolume.h"
#include "super.h"
#include "super-io.h"
#include "sysfs.h"
@ -475,6 +476,7 @@ static void __bch2_fs_free(struct bch_fs *c)
for (i = 0; i < BCH_TIME_STAT_NR; i++)
bch2_time_stats_exit(&c->times[i]);
bch2_fs_snapshots_exit(c);
bch2_fs_quota_exit(c);
bch2_fs_fsio_exit(c);
bch2_fs_ec_exit(c);
@ -694,6 +696,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
mutex_init(&c->usage_scratch_lock);
mutex_init(&c->bio_bounce_pages_lock);
mutex_init(&c->snapshot_table_lock);
spin_lock_init(&c->btree_write_error_lock);
@ -797,6 +800,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
bch2_fs_btree_key_cache_init(&c->btree_key_cache) ||
bch2_fs_btree_iter_init(c) ||
bch2_fs_btree_interior_update_init(c) ||
bch2_fs_subvolumes_init(c) ||
bch2_fs_io_init(c) ||
bch2_fs_encryption_init(c) ||
bch2_fs_compress_init(c) ||