RepoMirrors/btrfs-progs
1
0
Fork 0
mirror of https://github.com/kdave/btrfs-progs synced 2024-12-25 15:42:23 +00:00
Code Issues Packages Projects Releases Wiki Activity

Revert "libbtrfs: remove the support for fs without uuid tree"

Browse Source 
This reverts commit 83ab92512e.

The commit removed some old code that seemed to be unused but this
actually broke snapper. Revert the changes completely to the v6.3 ABI
level.

Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1212217
Issue: #672
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2023-09-01 12:01:33 +02:00
parent 7a0da24f52
commit f9b0da8e78
2 changed files with 412 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

392
libbtrfs/send-utils.c
View File

@ -199,6 +199,73 @@ static int btrfs_read_root_item(int mnt_fd, u64 root_id,
return 0;
}
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
static struct rb_node *tree_insert(struct rb_root *root,
struct subvol_info *si,
enum subvol_search_type type)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
struct subvol_info *entry;
__s64 comp;
while (*p) {
parent = *p;
if (type == subvol_search_by_received_uuid) {
entry = rb_entry(parent, struct subvol_info,
rb_received_node);
comp = memcmp(entry->received_uuid, si->received_uuid,
BTRFS_UUID_SIZE);
if (!comp) {
if (entry->stransid < si->stransid)
comp = -1;
else if (entry->stransid > si->stransid)
comp = 1;
else
comp = 0;
}
} else if (type == subvol_search_by_uuid) {
entry = rb_entry(parent, struct subvol_info,
rb_local_node);
comp = memcmp(entry->uuid, si->uuid, BTRFS_UUID_SIZE);
} else if (type == subvol_search_by_root_id) {
entry = rb_entry(parent, struct subvol_info,
rb_root_id_node);
comp = entry->root_id - si->root_id;
} else if (type == subvol_search_by_path) {
entry = rb_entry(parent, struct subvol_info,
rb_path_node);
comp = strcmp(entry->path, si->path);
} else {
BUG();
}
if (comp < 0)
p = &(*p)->rb_left;
else if (comp > 0)
p = &(*p)->rb_right;
else
return parent;
}
if (type == subvol_search_by_received_uuid) {
rb_link_node(&si->rb_received_node, parent, p);
rb_insert_color(&si->rb_received_node, root);
} else if (type == subvol_search_by_uuid) {
rb_link_node(&si->rb_local_node, parent, p);
rb_insert_color(&si->rb_local_node, root);
} else if (type == subvol_search_by_root_id) {
rb_link_node(&si->rb_root_id_node, parent, p);
rb_insert_color(&si->rb_root_id_node, root);
} else if (type == subvol_search_by_path) {
rb_link_node(&si->rb_path_node, parent, p);
rb_insert_color(&si->rb_path_node, root);
}
return NULL;
}
#endif
int btrfs_subvolid_resolve(int fd, char *path, size_t path_len, u64 subvol_id)
{
if (path_len < 1)
@ -297,6 +364,116 @@ static int btrfs_subvolid_resolve_sub(int fd, char *path, size_t *path_len,
return 0;
}
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
static int count_bytes(void *buf, int len, char b)
{
int cnt = 0;
int i;
for (i = 0; i < len; i++) {
if (((char *)buf)[i] == b)
cnt++;
}
return cnt;
}
void subvol_uuid_search_add(struct subvol_uuid_search *s,
struct subvol_info *si);
void subvol_uuid_search_add(struct subvol_uuid_search *s,
struct subvol_info *si)
{
int cnt;
tree_insert(&s->root_id_subvols, si, subvol_search_by_root_id);
tree_insert(&s->path_subvols, si, subvol_search_by_path);
cnt = count_bytes(si->uuid, BTRFS_UUID_SIZE, 0);
if (cnt != BTRFS_UUID_SIZE)
tree_insert(&s->local_subvols, si, subvol_search_by_uuid);
cnt = count_bytes(si->received_uuid, BTRFS_UUID_SIZE, 0);
if (cnt != BTRFS_UUID_SIZE)
tree_insert(&s->received_subvols, si,
subvol_search_by_received_uuid);
}
static struct subvol_info *tree_search(struct rb_root *root,
u64 root_id, const u8 *uuid,
u64 stransid, const char *path,
enum subvol_search_type type)
{
struct rb_node *n = root->rb_node;
struct subvol_info *entry;
__s64 comp;
while (n) {
if (type == subvol_search_by_received_uuid) {
entry = rb_entry(n, struct subvol_info,
rb_received_node);
comp = memcmp(entry->received_uuid, uuid,
BTRFS_UUID_SIZE);
if (!comp) {
if (entry->stransid < stransid)
comp = -1;
else if (entry->stransid > stransid)
comp = 1;
else
comp = 0;
}
} else if (type == subvol_search_by_uuid) {
entry = rb_entry(n, struct subvol_info, rb_local_node);
comp = memcmp(entry->uuid, uuid, BTRFS_UUID_SIZE);
} else if (type == subvol_search_by_root_id) {
entry = rb_entry(n, struct subvol_info,
rb_root_id_node);
comp = entry->root_id - root_id;
} else if (type == subvol_search_by_path) {
entry = rb_entry(n, struct subvol_info, rb_path_node);
comp = strcmp(entry->path, path);
} else {
BUG();
}
if (comp < 0)
n = n->rb_left;
else if (comp > 0)
n = n->rb_right;
else
return entry;
}
return NULL;
}
/*
* this function will be only called if kernel doesn't support uuid tree.
*/
static struct subvol_info *subvol_uuid_search_old(struct subvol_uuid_search *s,
u64 root_id, const u8 *uuid, u64 transid,
const char *path,
enum subvol_search_type type)
{
struct rb_root *root;
if (type == subvol_search_by_received_uuid)
root = &s->received_subvols;
else if (type == subvol_search_by_uuid)
root = &s->local_subvols;
else if (type == subvol_search_by_root_id)
root = &s->root_id_subvols;
else if (type == subvol_search_by_path)
root = &s->path_subvols;
else
return NULL;
return tree_search(root, root_id, uuid, transid, path, type);
}
#else
void subvol_uuid_search_add(struct subvol_uuid_search *s,
struct subvol_info *si)
{
if (si) {
free(si->path);
free(si);
}
}
#endif
static struct subvol_info *subvol_uuid_search2(struct subvol_uuid_search *s,
u64 root_id, const u8 *uuid, u64 transid,
const char *path,
@ -394,6 +571,11 @@ static struct subvol_info *subvol_uuid_search2(struct subvol_uuid_search *s,
struct btrfs_root_item root_item;
struct subvol_info *info = NULL;
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
if (!s->uuid_tree_existed)
return subvol_uuid_search_old(s, root_id, uuid, transid,
path, type);
#endif
switch (type) {
case subvol_search_by_received_uuid:
ret = btrfs_uuid_tree_lookup_any(s->mnt_fd, uuid,
@ -461,9 +643,219 @@ out:
return info;
}
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
static int is_uuid_tree_supported(int fd)
{
int ret;
struct btrfs_ioctl_search_args args;
struct btrfs_ioctl_search_key *sk = &args.key;
memset(&args, 0, sizeof(args));
sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
sk->min_objectid = BTRFS_UUID_TREE_OBJECTID;
sk->max_objectid = BTRFS_UUID_TREE_OBJECTID;
sk->max_type = BTRFS_ROOT_ITEM_KEY;
sk->min_type = BTRFS_ROOT_ITEM_KEY;
sk->max_offset = (u64)-1;
sk->max_transid = (u64)-1;
sk->nr_items = 1;
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
if (ret < 0)
return ret;
/* the ioctl returns the number of item it found in nr_items */
if (sk->nr_items == 0)
return 0;
return 1;
}
/*
* this function is mainly used to read all root items
* it will be only used when we use older kernel which uuid
* tree is not supported yet
*/
int subvol_uuid_search_init(int mnt_fd, struct subvol_uuid_search *s)
{
int ret;
struct btrfs_ioctl_search_args args;
struct btrfs_ioctl_search_key *sk = &args.key;
struct btrfs_ioctl_search_header *sh;
struct btrfs_root_item *root_item_ptr;
struct btrfs_root_item root_item = {};
struct subvol_info *si = NULL;
int root_item_valid = 0;
unsigned long off = 0;
int i;
s->mnt_fd = mnt_fd;
s->root_id_subvols = RB_ROOT;
s->local_subvols = RB_ROOT;
s->received_subvols = RB_ROOT;
s->path_subvols = RB_ROOT;
ret = is_uuid_tree_supported(mnt_fd);
if (ret < 0) {
fprintf(stderr,
"ERROR: check if we support uuid tree fails - %m\n");
return ret;
} else if (ret) {
/* uuid tree is supported */
s->uuid_tree_existed = 1;
return 0;
}
memset(&args, 0, sizeof(args));
sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
sk->max_objectid = (u64)-1;
sk->max_offset = (u64)-1;
sk->max_transid = (u64)-1;
sk->min_type = BTRFS_ROOT_ITEM_KEY;
sk->max_type = BTRFS_ROOT_BACKREF_KEY;
sk->nr_items = 4096;
while (1) {
ret = ioctl(mnt_fd, BTRFS_IOC_TREE_SEARCH, &args);
if (ret < 0) {
fprintf(stderr, "ERROR: can't perform the search - %m\n");
return ret;
}
if (sk->nr_items == 0)
break;
off = 0;
for (i = 0; i < sk->nr_items; i++) {
sh = (struct btrfs_ioctl_search_header *)(args.buf +
off);
off += sizeof(*sh);
if ((btrfs_search_header_objectid(sh) != 5 &&
btrfs_search_header_objectid(sh)
< BTRFS_FIRST_FREE_OBJECTID) ||
btrfs_search_header_objectid(sh)
> BTRFS_LAST_FREE_OBJECTID) {
goto skip;
}
if (btrfs_search_header_type(sh)
== BTRFS_ROOT_ITEM_KEY) {
/* older kernels don't have uuids+times */
if (btrfs_search_header_len(sh)
< sizeof(root_item)) {
root_item_valid = 0;
goto skip;
}
root_item_ptr = (struct btrfs_root_item *)
(args.buf + off);
memcpy(&root_item, root_item_ptr,
sizeof(root_item));
root_item_valid = 1;
} else if (btrfs_search_header_type(sh)
== BTRFS_ROOT_BACKREF_KEY ||
root_item_valid) {
char path_buf[PATH_MAX];
char *path;
if (!root_item_valid)
goto skip;
ret = btrfs_subvolid_resolve(mnt_fd, path_buf,
sizeof(path_buf),
btrfs_search_header_objectid(sh));
if (ret < 0) {
errno = -ret;
fprintf(stderr, "ERROR: unable to "
"resolve path "
"for root %llu: %m\n",
btrfs_search_header_objectid(sh));
goto out;
}
path = strdup(path_buf);
si = calloc(1, sizeof(*si));
si->root_id = btrfs_search_header_objectid(sh);
memcpy(si->uuid, root_item.uuid,
BTRFS_UUID_SIZE);
memcpy(si->parent_uuid, root_item.parent_uuid,
BTRFS_UUID_SIZE);
memcpy(si->received_uuid,
root_item.received_uuid,
BTRFS_UUID_SIZE);
si->ctransid = btrfs_root_ctransid(&root_item);
si->otransid = btrfs_root_otransid(&root_item);
si->stransid = btrfs_root_stransid(&root_item);
si->rtransid = btrfs_root_rtransid(&root_item);
si->path = path;
subvol_uuid_search_add(s, si);
root_item_valid = 0;
} else {
goto skip;
}
skip:
off += btrfs_search_header_len(sh);
/*
* record the mins in sk so we can make sure the
* next search doesn't repeat this root
*/
sk->min_objectid = btrfs_search_header_objectid(sh);
sk->min_offset = btrfs_search_header_offset(sh);
sk->min_type = btrfs_search_header_type(sh);
}
sk->nr_items = 4096;
if (sk->min_offset < (u64)-1)
sk->min_offset++;
else if (sk->min_objectid < (u64)-1) {
sk->min_objectid++;
sk->min_offset = 0;
sk->min_type = 0;
} else
break;
}
out:
return ret;
}
void subvol_uuid_search_finit(struct subvol_uuid_search *s);
void subvol_uuid_search_finit(struct subvol_uuid_search *s)
{
struct rb_root *root = &s->root_id_subvols;
struct rb_node *node;
if (!s->uuid_tree_existed)
return;
while ((node = rb_first(root))) {
struct subvol_info *entry =
rb_entry(node, struct subvol_info, rb_root_id_node);
free(entry->path);
rb_erase(node, root);
free(entry);
}
s->root_id_subvols = RB_ROOT;
s->local_subvols = RB_ROOT;
s->received_subvols = RB_ROOT;
s->path_subvols = RB_ROOT;
}
#else
int subvol_uuid_search_init(int mnt_fd, struct subvol_uuid_search *s)
{
s->mnt_fd = mnt_fd;
return 0;
}
void subvol_uuid_search_finit(struct subvol_uuid_search *s)
{
}
#endif

20
libbtrfs/send-utils.h
View File

@ -35,6 +35,12 @@
extern "C" {
#endif
/*
* Compatibility code for kernels < 3.12; the UUID tree is not available there
* and we have to do the slow search. This should be deprecated someday.
*/
#define BTRFS_COMPAT_SEND_NO_UUID_TREE 1
enum subvol_search_type {
subvol_search_by_root_id,
subvol_search_by_uuid,
@ -43,6 +49,12 @@ enum subvol_search_type {
};
struct subvol_info {
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
struct rb_node rb_root_id_node;
struct rb_node rb_local_node;
struct rb_node rb_received_node;
struct rb_node rb_path_node;
#endif
u64 root_id;
u8 uuid[BTRFS_UUID_SIZE];
@ -58,6 +70,14 @@ struct subvol_info {
struct subvol_uuid_search {
int mnt_fd;
#ifdef BTRFS_COMPAT_SEND_NO_UUID_TREE
int uuid_tree_existed;
struct rb_root root_id_subvols;
struct rb_root local_subvols;
struct rb_root received_subvols;
struct rb_root path_subvols;
#endif
};
int subvol_uuid_search_init(int mnt_fd, struct subvol_uuid_search *s);