From: Goffredo Baroncelli <kreij...@inwind.it>
Use the new ioctl BTRFS_IOC_GET_CHUNK_INFO in load_chunk_info() instead of the
BTRFS_IOC_TREE_SEARCH. The old method is still present as fallback for
compatibility reason.
The goal is to avoid BTRFS_IOC_GET_CHUNK_INFO because it requires root
privileges.
Signed-off-by: Goffredo Baroncelli <kreij...@inwind.it>
---
cmds-fi-usage.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
ioctl.h | 60 +++++++++++++++++++++++++++++++
2 files changed, 165 insertions(+), 3 deletions(-)
diff --git a/cmds-fi-usage.c b/cmds-fi-usage.c
index 6c846c15..6a101e28 100644
--- a/cmds-fi-usage.c
+++ b/cmds-fi-usage.c
@@ -36,7 +36,7 @@
/*
* Add the chunk info to the chunk_info list
*/
-static int add_info_to_list(struct chunk_info **info_ptr,
+static int legacy_add_info_to_list(struct chunk_info **info_ptr,
int *info_count,
struct btrfs_chunk *chunk)
{
@@ -127,7 +127,8 @@ static int cmp_chunk_info(const void *a, const void *b)
((struct chunk_info *)b)->type);
}
-static int load_chunk_info(int fd, struct chunk_info **info_ptr, int
*info_count)
+static int legacy_load_chunk_info(int fd, struct chunk_info **info_ptr,
+ int *info_count)
{
int ret;
struct btrfs_ioctl_search_args args;
@@ -180,7 +181,7 @@ static int load_chunk_info(int fd, struct chunk_info
**info_ptr, int *info_count
off += sizeof(*sh);
item = (struct btrfs_chunk *)(args.buf + off);
- ret = add_info_to_list(info_ptr, info_count, item);
+ ret = legacy_add_info_to_list(info_ptr, info_count,
item);
if (ret) {
*info_ptr = NULL;
return 1;
@@ -213,6 +214,107 @@ static int load_chunk_info(int fd, struct chunk_info
**info_ptr, int *info_count
return 0;
}
+/*
+ * Add the chunk info to the chunk_info list
+ */
+static int add_info_to_list(struct chunk_info **info_ptr,
+ int *info_count,
+ struct btrfs_chunk_info *chunk)
+{
+
+ u64 type = chunk->type;
+ u64 size = chunk->length;
+ int num_stripes = chunk->num_stripes;
+ int j;
+
+ for (j = 0 ; j < num_stripes ; j++) {
+ int i;
+ struct chunk_info *p = NULL;
+ u64 devid;
+
+ devid = chunk->stripes[j].devid;
+
+ for (i = 0 ; i < *info_count ; i++)
+ if ((*info_ptr)[i].type == type &&
+ (*info_ptr)[i].devid == devid &&
+ (*info_ptr)[i].num_stripes == num_stripes) {
+ p = (*info_ptr) + i;
+ break;
+ }
+
+ if (!p) {
+ int tmp = sizeof(struct btrfs_chunk) *
+ (*info_count + 1);
+ struct chunk_info *res = realloc(*info_ptr, tmp);
+
+ if (!res) {
+ free(*info_ptr);
+ error("not enough memory");
+ return -ENOMEM;
+ }
+
+ *info_ptr = res;
+ p = res + *info_count;
+ (*info_count)++;
+
+ p->devid = devid;
+ p->type = type;
+ p->size = 0;
+ p->num_stripes = num_stripes;
+ }
+
+ p->size += size;
+
+ }
+
+ return 0;
+
+}
+
+static int load_chunk_info(int fd, struct chunk_info **info_ptr,
+ int *info_count)
+{
+
+ char buf[4096];
+ struct btrfs_ioctl_chunk_info *bici =
+ (struct btrfs_ioctl_chunk_info *)buf;
+ int cont;
+
+ bici->buf_size = sizeof(buf);
+ bici->offset = (u64)0;
+
+ do {
+ int i;
+ struct btrfs_chunk_info *ci;
+ int ret;
+
+ cont = false;
+ ret = ioctl(fd, BTRFS_IOC_GET_CHUNK_INFO, bici);
+ if (ret < 0) {
+ int e = errno;
+
+ if (e == ENOTTY)
+ return legacy_load_chunk_info(fd, info_ptr,
+ info_count);
+ else if (e == EAGAIN)
+ cont = true;
+ else
+ return -e;
+ }
+
+ ci = btrfs_first_chunk_info(bici);
+ for (i = 0 ; i < bici->items_count ; i++) {
+ add_info_to_list(info_ptr, info_count, ci);
+ ci = btrfs_next_chunk_info(ci);
+ }
+
+ } while (cont);
+
+ qsort(*info_ptr, *info_count, sizeof(struct chunk_info),
+ cmp_chunk_info);
+
+ return 0;
+}
/*
* Helper to sort the struct btrfs_ioctl_space_info
*/
diff --git a/ioctl.h b/ioctl.h
index 709e996f..11a2c239 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -672,6 +672,64 @@ BUILD_ASSERT(sizeof(struct btrfs_ioctl_send_args_64) ==
72);
#define BTRFS_IOC_SEND_64_COMPAT_DEFINED 1
+struct btrfs_chunk_info_stripe {
+ __u64 devid;
+ __u64 offset;
+ __u8 dev_uuid[BTRFS_UUID_SIZE];
+};
+
+struct btrfs_chunk_info {
+ /* logical start of this chunk */
+ __u64 offset;
+ /* size of this chunk in bytes */
+ __u64 length;
+
+ __u64 stripe_len;
+ __u64 type;
+
+ /* 2^16 stripes is quite a lot, a second limit is the size of a single
+ * item in the btree
+ */
+ __u16 num_stripes;
+
+ /* sub stripes only matter for raid10 */
+ __u16 sub_stripes;
+
+ struct btrfs_chunk_info_stripe stripes[1];
+ /* additional stripes go here */
+};
+
+struct btrfs_ioctl_chunk_info {
+ /* offset to start the search; after the ioctl, this field contains
+ * the next offset to start a search
+ */
+ u64 offset; /* in/out */
+ /* size of the passed buffer, including btrfs_ioctl_chunk_info */
+ u32 buf_size; /* in */
+ /* number of items returned */
+ u32 items_count; /* out */
+};
+
+static inline struct btrfs_chunk_info *
+btrfs_first_chunk_info(struct btrfs_ioctl_chunk_info *bici)
+{
+ return (struct btrfs_chunk_info *)((char *)bici +
+ sizeof(struct btrfs_ioctl_chunk_info));
+}
+
+static inline int btrfs_chunk_info_size(struct btrfs_chunk_info *ci)
+{
+ return sizeof(struct btrfs_chunk_info) +
+ sizeof(struct btrfs_chunk_info_stripe) * (ci->num_stripes-1);
+}
+
+static inline struct btrfs_chunk_info *
+btrfs_next_chunk_info(struct btrfs_chunk_info *ci)
+{
+ return (struct btrfs_chunk_info *)((char *)ci +
+ btrfs_chunk_info_size(ci));
+}
+
/* Error codes as returned by the kernel */
enum btrfs_err_code {
notused,
@@ -828,6 +886,8 @@ static inline char *btrfs_err_str(enum btrfs_err_code
err_code)
struct btrfs_ioctl_feature_flags[3])
#define BTRFS_IOC_RM_DEV_V2 _IOW(BTRFS_IOCTL_MAGIC, 58, \
struct btrfs_ioctl_vol_args_v2)
+#define BTRFS_IOC_GET_CHUNK_INFO _IOR(BTRFS_IOCTL_MAGIC, 59, \
+ struct btrfs_ioctl_chunk_info)
#ifdef __cplusplus
}
#endif
--
2.14.1
--
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