The user land progs needs a simple way to see
the raw list of disks and its parameters as seen
by the btrfs kernel.
As of now btrfs-devlist uses this ioctl.
Signed-off-by: Anand Jain <anand.j...@oracle.com>
---
fs/btrfs/super.c | 86 +++++++++++++++++++++++++++
fs/btrfs/volumes.c | 145 +++++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/volumes.h | 3 +
include/uapi/linux/btrfs.h | 53 ++++++++++++++++-
4 files changed, 286 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 59172ed..f3660f5 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1957,6 +1957,89 @@ static struct file_system_type btrfs_fs_type = {
};
MODULE_ALIAS_FS("btrfs");
+static int btrfs_ioc_get_devlist(void __user *arg)
+{
+ int ret = 0;
+ u64 sz_devlist_arg;
+ u64 sz_devlist;
+ u64 u_sz_devlist_arg;
+ u64 u_sz_devlist;
+ u64 sz_out;
+
+ struct btrfs_ioctl_devlist_args *devlist_arg;
+ struct btrfs_ioctl_devlist_args *tmp_devlist_arg;
+ struct btrfs_ioctl_devlist *devlist;
+
+ u64 cnt = 0, ucnt;
+
+ sz_devlist_arg = sizeof(*devlist_arg);
+ sz_devlist = sizeof(*devlist);
+
+ /* Check if the user land and kernel ioctl struct match */
+ if (copy_from_user(&u_sz_devlist_arg,
+ (struct btrfs_ioctl_devlist_args __user *)(arg +
+ offsetof(struct btrfs_ioctl_devlist_args, sz_self)),
+ sizeof(u_sz_devlist_arg)))
+ return -EFAULT;
+
+ if (copy_from_user(&u_sz_devlist,
+ (struct btrfs_ioctl_devlist_args __user *)(arg +
+ sz_devlist_arg +
+ offsetof(struct btrfs_ioctl_devlist, sz_self)),
+ sizeof(u_sz_devlist)))
+ return -EFAULT;
+
+ if (u_sz_devlist_arg != sz_devlist_arg ||
+ u_sz_devlist != sz_devlist) {
+ if (copy_to_user(arg +
+ offsetof(struct btrfs_ioctl_devlist_args, sz_self),
+ &sz_devlist_arg, sizeof(sz_devlist_arg)))
+ return -EFAULT;
+ if (copy_to_user(arg +
+ sz_devlist_arg +
+ offsetof(struct btrfs_ioctl_devlist, sz_self),
+ &sz_devlist, sizeof(sz_devlist)))
+ return -EFAULT;
+ return 2;
+ }
+
+ if (copy_from_user(&ucnt,
+ (struct btrfs_ioctl_devlist_args __user *)(arg +
+ offsetof(struct btrfs_ioctl_devlist_args, count)),
+ sizeof(ucnt)))
+ return -EFAULT;
+
+ cnt = btrfs_get_devlist_cnt();
+
+ if (cnt > ucnt) {
+ if (copy_to_user(arg +
+ offsetof(struct btrfs_ioctl_devlist_args, count),
+ &cnt, sizeof(cnt)))
+ return -EFAULT;
+ return 1;
+ }
+
+ sz_out = sz_devlist_arg + sz_devlist * cnt;
+
+ tmp_devlist_arg = devlist_arg = memdup_user(arg, sz_out);
+ if (IS_ERR(devlist_arg))
+ return PTR_ERR(devlist_arg);
+
+ devlist = (struct btrfs_ioctl_devlist *) (++tmp_devlist_arg);
+ cnt = btrfs_get_devlist(devlist, cnt);
+ devlist_arg->count = cnt;
+
+ if (copy_to_user(arg, devlist_arg, sz_out)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ ret = 0;
+out:
+ kfree(devlist_arg);
+ return ret;
+
+}
+
static int btrfs_ioc_get_fslist(void __user *arg)
{
int ret = 0;
@@ -2019,6 +2102,9 @@ static long btrfs_control_ioctl(struct file *file,
unsigned int cmd,
return -EPERM;
switch (cmd) {
+ case BTRFS_IOC_GET_DEVS:
+ ret = btrfs_ioc_get_devlist(argp);
+ break;
case BTRFS_IOC_SCAN_DEV:
vol = memdup_user((void __user *)arg, sizeof(*vol));
if (IS_ERR(vol))
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 92b3d4d..15c533d 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -229,6 +229,151 @@ error:
return ret;
}
+int btrfs_get_devlist_cnt(void)
+{
+ int cnt = 0;
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices;
+ struct btrfs_fs_devices *cur_fs_devices;
+
+ mutex_lock(&uuid_mutex);
+ list_for_each_entry(cur_fs_devices, &fs_uuids, list) {
+
+ fs_devices = cur_fs_devices;
+again_dev_cnt:
+ list_for_each_entry(device, &fs_devices->devices, dev_list)
+ cnt++;
+
+ fs_devices = fs_devices->seed;
+ if (fs_devices)
+ goto again_dev_cnt;
+ }
+
+ mutex_unlock(&uuid_mutex);
+
+ return cnt;
+}
+
+u64 btrfs_get_devlist(struct btrfs_ioctl_devlist *dev, u64 alloc_cnt)
+{
+ u64 cnt = 0;
+
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices;
+ struct btrfs_fs_devices *cur_fs_devices;
+ struct btrfs_fs_devices *sprout_fs_devices;
+
+ mutex_lock(&uuid_mutex);
+ /* Todo: there must be better way of doing this */
+ list_for_each_entry(cur_fs_devices, &fs_uuids, list) {
+
+ mutex_lock(&cur_fs_devices->device_list_mutex);
+
+ fs_devices = cur_fs_devices;
+ sprout_fs_devices = NULL;
+
+again_dev:
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+
+ if (!(cnt < alloc_cnt))
+ break;
+
+ dev->dev_root_addr = (u64)device->dev_root;
+ if (device->dev_root)
+ memcpy(dev->root_fsid,
+ device->dev_root->fs_info->fsid,
+ BTRFS_FSID_SIZE);
+ dev->fs_addr = (u64)fs_devices;
+ dev->dev_addr = (u64)device;
+ memcpy(dev->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
+
+ if (fs_devices->seed) {
+ memcpy(dev->seed_fsid, fs_devices->seed->fsid,
+ BTRFS_FSID_SIZE);
+ dev->seed_fs_addr = (u64)fs_devices->seed;
+ } else
+ memset(dev->seed_fsid, 0, BTRFS_FSID_SIZE);
+
+ if (sprout_fs_devices) {
+ memcpy(dev->sprout_fsid,
sprout_fs_devices->fsid,
+ BTRFS_FSID_SIZE);
+ dev->sprout_fs_addr = (u64)sprout_fs_devices;
+ } else
+ memset(dev->sprout_fsid, 0, BTRFS_FSID_SIZE);
+
+ dev->fs_num_devices = fs_devices->num_devices;
+ dev->fs_open_devices = fs_devices->open_devices;
+ dev->fs_rw_devices = fs_devices->rw_devices;
+ dev->fs_missing_devices = fs_devices->missing_devices;
+ dev->fs_total_rw_bytes = fs_devices->total_rw_bytes;
+ dev->fs_num_can_discard = fs_devices->num_can_discard;
+ dev->fs_total_devices = fs_devices->total_devices;
+
+ dev->flags = 0;
+
+ if (fs_devices->opened)
+ dev->flags |= BTRFS_FS_MOUNTED;
+ if (fs_devices->seeding)
+ dev->flags |= BTRFS_FS_SEEDING;
+ if (fs_devices->rotating)
+ dev->flags |= BTRFS_FS_ROTATING;
+
+ dev->gen = device->generation;
+ dev->devid = device->devid;
+ dev->total_bytes = device->total_bytes;
+ dev->disk_total_bytes = device->disk_total_bytes;
+ dev->bytes_used = device->bytes_used;
+ dev->type = device->type;
+ dev->io_align = device->io_align;
+ dev->io_width = device->io_width;
+ dev->sector_size = device->sector_size;
+ dev->fmode = device->mode;
+
+ if (device->writeable)
+ dev->flags |= BTRFS_DEV_WRITEABLE;
+ if (device->in_fs_metadata)
+ dev->flags |= BTRFS_DEV_IN_FS_MD;
+ if (device->missing)
+ dev->flags |= BTRFS_DEV_MISSING;
+ if (device->can_discard)
+ dev->flags |= BTRFS_DEV_CAN_DISCARD;
+ if (device->is_tgtdev_for_dev_replace)
+ dev->flags |= BTRFS_DEV_REPLACE_TGT;
+ if (device->running_pending)
+ dev->flags |= BTRFS_DEV_RUN_PENDING;
+ if (device->nobarriers)
+ dev->flags |= BTRFS_DEV_NOBARRIERS;
+ if (device->dev_stats_valid)
+ dev->flags |= BTRFS_DEV_STATS_VALID;
+ if (device->bdev)
+ dev->flags |= BTRFS_DEV_BDEV;
+
+ memcpy(dev->uuid, device->uuid, BTRFS_UUID_SIZE);
+ if (device->name) {
+ rcu_read_lock();
+ memcpy(dev->name, rcu_str_deref(device->name),
+ BTRFS_PATH_NAME_MAX);
+ rcu_read_unlock();
+ } else {
+ memset(dev->name, 0, BTRFS_PATH_NAME_MAX);
+ }
+ dev++;
+ cnt++;
+ }
+
+ if (fs_devices->seed) {
+ sprout_fs_devices = fs_devices;
+ fs_devices = fs_devices->seed;
+ goto again_dev;
+ }
+
+ mutex_unlock(&cur_fs_devices->device_list_mutex);
+ }
+ mutex_unlock(&uuid_mutex);
+
+ return cnt;
+}
+
static void requeue_list(struct btrfs_pending_bios *pending_bios,
struct bio *head, struct bio *tail)
{
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index c602416..e71dc9e 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -281,6 +281,9 @@ struct btrfs_balance_control {
struct btrfs_balance_progress stat;
};
+int btrfs_get_devlist_cnt(void);
+u64 btrfs_get_devlist(struct btrfs_ioctl_devlist *devlist, u64 ucnt);
+
int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
u64 end, u64 *length);
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index f8c4bd6..3175e38 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -534,6 +534,8 @@ static inline char *btrfs_err_str(enum btrfs_err_code
err_code)
/* fs flags */
#define BTRFS_FS_MOUNTED (1LLU << 0)
+#define BTRFS_FS_SEEDING (1LLU << 1)
+#define BTRFS_FS_ROTATING (1LLU << 2)
struct btrfs_ioctl_fslist {
__u64 self_sz; /* in/out */
@@ -549,6 +551,54 @@ struct btrfs_ioctl_fslist_args {
__u64 count; /* out */
};
+#define BTRFS_DEV_WRITEABLE (1LLU << 8)
+#define BTRFS_DEV_IN_FS_MD (1LLU << 9)
+#define BTRFS_DEV_MISSING (1LLU << 10)
+#define BTRFS_DEV_CAN_DISCARD (1LLU << 11)
+#define BTRFS_DEV_REPLACE_TGT (1LLU << 12)
+#define BTRFS_DEV_RUN_PENDING (1LLU << 13)
+#define BTRFS_DEV_NOBARRIERS (1LLU << 14)
+#define BTRFS_DEV_STATS_VALID (1LLU << 15)
+#define BTRFS_DEV_BDEV (1LLU << 16)
+
+struct btrfs_ioctl_devlist {
+ __u64 sz_self;
+ __u64 dev_root_addr;
+ __u64 fs_addr;
+ __u64 dev_addr;
+ __u64 seed_fs_addr;
+ __u64 sprout_fs_addr;
+ __u64 fs_num_devices;
+ __u64 fs_open_devices;
+ __u64 fs_rw_devices;
+ __u64 fs_missing_devices;
+ __u64 fs_total_rw_bytes;
+ __u64 fs_num_can_discard;
+ __u64 fs_total_devices;
+ __u64 gen;
+ __u64 flags;
+ __u64 devid;
+ __u64 total_bytes;
+ __u64 disk_total_bytes;
+ __u64 bytes_used;
+ __u64 type;
+ __u64 fmode;
+ __u32 io_align;
+ __u32 io_width;
+ __u32 sector_size;
+ __u8 fsid[BTRFS_FSID_SIZE];
+ __u8 uuid[BTRFS_UUID_SIZE];
+ __u8 seed_fsid[BTRFS_FSID_SIZE];
+ __u8 sprout_fsid[BTRFS_UUID_SIZE];
+ __u8 root_fsid[BTRFS_FSID_SIZE];
+ __u8 name[BTRFS_PATH_NAME_MAX];
+}__attribute__ ((__packed__));
+
+struct btrfs_ioctl_devlist_args {
+ __u64 sz_self; /* in/out */
+ __u64 count; /* in/out */
+};
+
#define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \
struct btrfs_ioctl_vol_args)
#define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \
@@ -653,5 +703,6 @@ struct btrfs_ioctl_fslist_args {
struct btrfs_ioctl_feature_flags[2])
#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \
struct btrfs_ioctl_feature_flags[3])
-
+#define BTRFS_IOC_GET_DEVS _IOWR(BTRFS_IOCTL_MAGIC, 59, \
+ struct btrfs_ioctl_devlist_args)
#endif /* _UAPI_LINUX_BTRFS_H */
--
2.0.0.153.g79dcccc
--
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