New feature to list up subvolume/snapshots under
specified tree of file is introduced to btrfsctl.
This patch should apply with corresponding patch
for kernel.
Signed-off-by: TARUISI Hiroaki <taruishi.hir...@jp.fujitsu.com>
---
btrfsctl.c | 191 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
ioctl.h | 32 ++++++++++
2 files changed, 223 insertions(+)
Index: b/btrfsctl.c
===================================================================
--- a/btrfsctl.c 2009-11-16 11:18:57.000000000 +0900
+++ b/btrfsctl.c 2009-11-18 12:09:37.000000000 +0900
@@ -47,6 +47,7 @@ static void print_usage(void)
{
printf("usage: btrfsctl [ -d file|dir] [ -s snap_name subvol|tree ]\n");
printf(" [-r size] [-A device] [-a] [-c] [-D dir .]\n");
+ printf(" [-l dir]\n");
printf("\t-d filename: defragments one file\n");
printf("\t-d directory: defragments the entire Btree\n");
printf("\t-s snap_name dir: creates a new snapshot of dir\n");
@@ -56,6 +57,7 @@ static void print_usage(void)
printf("\t-a: scans all devices for Btrfs filesystems\n");
printf("\t-c: forces a single FS sync\n");
printf("\t-D: delete snapshot\n");
+ printf("\t-l file: listing snapshot/subvolume under a subvolume\n");
printf("%s\n", BTRFS_BUILD_VERSION);
exit(1);
}
@@ -88,6 +90,169 @@ static int open_file_or_dir(const char *
}
return fd;
}
+
+static noinline int btrfs_gather_under_one_subvolume(int fd,
+ unsigned long command,
+ struct btrfs_ioctl_subvol_args *svargs,
+ u64 tree_id,
+ struct list_head *list,
+ int len)
+{
+ u64 last_tree = 0ULL;
+ int i, ret = 1, local_size;
+
+ while (ret > 0) {
+
+ svargs->leaf = malloc(len);
+ if (!svargs->leaf)
+ return -1;
+ svargs->len = len;
+ svargs->leaf->len = len;
+ svargs->leaf->nritems = 0;
+ svargs->leaf->last_tree = last_tree;
+ svargs->leaf->parent_tree = tree_id;
+
+again:
+ ret = ioctl(fd, command, svargs);
+ if (ret < 0) {
+ free(svargs->leaf);
+ svargs->leaf = NULL;
+ return -1;
+ }
+ if (svargs->leaf->nritems == 0) {
+ free(svargs->leaf);
+ if (ret > 0) {
+ local_size = (svargs->next_len + 1) * 2 +
+ offsetof(struct
btrfs_ioctl_subvol_leaf, items) +
+ sizeof(struct
btrfs_ioctl_subvol_items)*2;
+ svargs->leaf = malloc(local_size);
+ if (!svargs->leaf)
+ return -1;
+ svargs->len = local_size;
+ svargs->leaf->len = local_size;
+ svargs->leaf->last_tree = last_tree;
+ svargs->leaf->parent_tree = tree_id;
+ goto again;
+ }
+ } else {
+ for (i = 0; i < svargs->leaf->nritems; i++)
+
INIT_LIST_HEAD(&svargs->leaf->items[i].children);
+ list_add_tail(&svargs->leaf->brother, list);
+ last_tree = svargs->leaf->last_tree;
+ }
+ }
+ return 0;
+}
+
+int btrfs_gather_subvolumes(int fd, unsigned long command,
+ struct btrfs_ioctl_subvol_args *svargs,
+ u64 tree_id, struct list_head *list_top, int len)
+{
+ struct btrfs_ioctl_subvol_leaf *cur;
+ int i;
+
+ if (btrfs_gather_under_one_subvolume(fd, command, svargs, tree_id,
+ list_top, len))
+ return -1;
+ list_for_each_entry(cur, list_top, brother) {
+ for(i = 0; i < cur->nritems; i++) {
+ if (btrfs_gather_subvolumes( fd, command, svargs,
+ cur->items[i].tree_id, &cur->items[i].children,
len))
+ return -1;
+ }
+ }
+ return 0;
+}
+
+int btrfs_free_subvolume_info(struct list_head *list_top)
+{
+ struct btrfs_ioctl_subvol_leaf *cur, *tmp;
+ int i;
+
+ list_for_each_entry_safe(cur, tmp, list_top, brother) {
+ for(i = 0; i < cur->nritems; i++) {
+ if (!list_empty(&cur->items[i].children))
+
btrfs_free_subvolume_info(&cur->items[i].children);
+ }
+ list_del(&cur->brother);
+ free(cur);
+ }
+ return 0;
+}
+
+int btrfs_show_subvolume(struct list_head *list_top, char *path,
+ int *seq)
+{
+ int nr = *seq, i;
+ int base_path_len, path_len;
+ struct btrfs_ioctl_subvol_leaf *cur;
+
+ base_path_len = strlen(path);
+ list_for_each_entry(cur, list_top, brother) {
+ for (i = 0; i < cur->nritems; i++) {
+ nr++;
+ path_len = strlen((char *)cur +
+ cur->items[i].path_offset);
+ if (base_path_len + path_len + 1 > BTRFS_PATH_NAME_MAX)
+ return -1;
+ strcpy(path+base_path_len,
+ (char *)cur+cur->items[i].path_offset);
+ strcat(path+base_path_len, "/");
+ printf("%5d\t%10llu\t%s\n", nr,
+ cur->items[i].tree_id, path);
+ if (!list_empty(&cur->items[i].children))
+ if
(btrfs_show_subvolume(&cur->items[i].children,
+ path, &nr))
+ return -1;
+ }
+ }
+ *seq = nr;
+ return 0;
+}
+
+
+int btrfs_list_subvolumes(int fd, unsigned long command)
+{
+ struct btrfs_ioctl_subvol_args *svargs;
+ int len, seq = 0, ret = 0;
+ char *path;
+
+ svargs = malloc(sizeof(struct btrfs_ioctl_subvol_args)
+ + BTRFS_PATH_NAME_MAX + 1);
+ if (!svargs)
+ return -1;
+ INIT_LIST_HEAD(&svargs->list_top);
+ svargs->base_path = (char *)(svargs+1);
+
+ len = (BTRFS_SUBVOL_LEAF_SIZE_MIN + getpagesize() - 1) &
+ ~(getpagesize() - 1);
+
+ if (btrfs_gather_subvolumes(fd, command, svargs, 0,
+ &svargs->list_top, len)) {
+ ret = -1;
+ goto out;
+ }
+
+ printf(" Base path = %s\n", svargs->base_path);
+ printf(" No.\t Tree ID\tSubvolume Relative Path\n");
+
+ path = malloc(BTRFS_PATH_NAME_MAX + 1);
+ if (!path) {
+ ret = -1;
+ goto out;
+ }
+ path[0]='\0';
+ if(btrfs_show_subvolume(&svargs->list_top, path, &seq)) {
+ ret = -1;
+ goto out;
+ }
+ if (seq == 0)
+ printf("\t\tNo Subvolumes\n");
+out:
+ btrfs_free_subvolume_info(&svargs->list_top);
+ return ret;
+}
+
int main(int ac, char **av)
{
char *fname = NULL;
@@ -191,6 +356,30 @@ int main(int ac, char **av)
command = BTRFS_IOC_RESIZE;
} else if (strcmp(av[i], "-c") == 0) {
command = BTRFS_IOC_SYNC;
+ } else if (strcmp(av[i], "-l") == 0) {
+ if (i >= ac - 1) {
+ fprintf(stderr, "-l requires an arg\n");
+ print_usage();
+ }
+ fullpath = av[i + 1];
+ snap_location = strdup(fullpath);
+ snap_fd = open_file_or_dir(snap_location);
+
+ name = strdup(fullpath);
+ name = basename(name);
+ len = strlen(name);
+
+ if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+ fprintf(stderr,
+ "listing subvolume name zero length or
too long\n");
+ exit(1);
+ }
+ if (strchr(name, '/')) {
+ fprintf(stderr,
+ "error: / not allowed in names\n");
+ exit(1);
+ }
+ command = BTRFS_IOC_SNAP_LISTING;
}
}
if (command == 0) {
@@ -219,6 +408,8 @@ int main(int ac, char **av)
if (command == BTRFS_IOC_SNAP_CREATE) {
args.fd = fd;
ret = ioctl(snap_fd, command, &args);
+ } else if (command == BTRFS_IOC_SNAP_LISTING) {
+ ret = btrfs_list_subvolumes(snap_fd, command);
} else
ret = ioctl(fd, command, &args);
if (ret < 0) {
Index: b/ioctl.h
===================================================================
--- a/ioctl.h 2009-11-16 11:18:57.000000000 +0900
+++ b/ioctl.h 2009-11-18 10:21:22.000000000 +0900
@@ -20,16 +20,46 @@
#define __IOCTL_
#include <asm/types.h>
#include <linux/ioctl.h>
+#include "kerncompat.h"
+#include "list.h"
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_VOL_NAME_MAX 255
#define BTRFS_PATH_NAME_MAX 4087
+#define BTRFS_SUBVOL_LIST_MAX 3
struct btrfs_ioctl_vol_args {
__s64 fd;
char name[BTRFS_PATH_NAME_MAX + 1];
};
+struct btrfs_ioctl_subvol_args {
+ int len;
+ int next_len;
+ char *base_path;
+ struct btrfs_ioctl_subvol_leaf *leaf;
+ struct list_head list_top;
+};
+
+struct btrfs_ioctl_subvol_items {
+ u64 tree_id;
+ struct list_head children;
+ int path_offset;
+ int len;
+};
+
+struct btrfs_ioctl_subvol_leaf {
+ int len;
+ int nritems;
+ u64 parent_tree;
+ u64 last_tree;
+ struct list_head brother;
+ struct btrfs_ioctl_subvol_items items[];
+};
+
+#define BTRFS_SUBVOL_LEAF_SIZE_MIN sizeof(struct btrfs_ioctl_subvol_leaf) + \
+ sizeof(struct btrfs_ioctl_subvol_items)
+
#define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \
struct btrfs_ioctl_vol_args)
#define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \
@@ -59,4 +89,6 @@ struct btrfs_ioctl_vol_args {
#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
struct btrfs_ioctl_vol_args)
+#define BTRFS_IOC_SNAP_LISTING _IOWR(BTRFS_IOCTL_MAGIC, 16, \
+ struct btrfs_ioctl_subvol_args)
#endif
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