blob: fcedc43ef291a208128da00409219faf0e390984 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/slab.h>
#include <linux/ratelimit.h>
#include <linux/kthread.h>
#include <linux/semaphore.h>
#include <linux/uuid.h>
#include <linux/list_sort.h>
#include <linux/namei.h>
#include "misc.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "volumes.h"
#include "raid56.h"
#include "rcu-string.h"
#include "dev-replace.h"
#include "sysfs.h"
#include "tree-checker.h"
#include "space-info.h"
#include "block-group.h"
#include "discard.h"
#include "zoned.h"
#include "fs.h"
#include "accessors.h"
#include "uuid-tree.h"
#include "ioctl.h"
#include "relocation.h"
#include "scrub.h"
#include "super.h"
#include "raid-stripe-tree.h"
#define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \
BTRFS_BLOCK_GROUP_RAID10 | \
BTRFS_BLOCK_GROUP_RAID56_MASK)
struct btrfs_io_geometry {
u32 stripe_index;
u32 stripe_nr;
int mirror_num;
int num_stripes;
u64 stripe_offset;
u64 raid56_full_stripe_start;
int max_errors;
enum btrfs_map_op op;
};
const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
[BTRFS_RAID_RAID10] = {
.sub_stripes = 2,
.dev_stripes = 1,
.devs_max = 0, /* 0 == as many as possible */
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 2,
.ncopies = 2,
.nparity = 0,
.raid_name = "raid10",
.bg_flag = BTRFS_BLOCK_GROUP_RAID10,
.mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 2,
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 2,
.ncopies = 2,
.nparity = 0,
.raid_name = "raid1",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1,
.mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1C3] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 3,
.devs_min = 3,
.tolerated_failures = 2,
.devs_increment = 3,
.ncopies = 3,
.nparity = 0,
.raid_name = "raid1c3",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1C3,
.mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1C4] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 4,
.devs_min = 4,
.tolerated_failures = 3,
.devs_increment = 4,
.ncopies = 4,
.nparity = 0,
.raid_name = "raid1c4",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1C4,
.mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET,
},
[BTRFS_RAID_DUP] = {
.sub_stripes = 1,
.dev_stripes = 2,
.devs_max = 1,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 2,
.nparity = 0,
.raid_name = "dup",
.bg_flag = BTRFS_BLOCK_GROUP_DUP,
.mindev_error = 0,
},
[BTRFS_RAID_RAID0] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 1,
.nparity = 0,
.raid_name = "raid0",
.bg_flag = BTRFS_BLOCK_GROUP_RAID0,
.mindev_error = 0,
},
[BTRFS_RAID_SINGLE] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 1,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 1,
.nparity = 0,
.raid_name = "single",
.bg_flag = 0,
.mindev_error = 0,
},
[BTRFS_RAID_RAID5] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 1,
.ncopies = 1,
.nparity = 1,
.raid_name = "raid5",
.bg_flag = BTRFS_BLOCK_GROUP_RAID5,
.mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
},
[BTRFS_RAID_RAID6] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 3,
.tolerated_failures = 2,
.devs_increment = 1,
.ncopies = 1,
.nparity = 2,
.raid_name = "raid6",
.bg_flag = BTRFS_BLOCK_GROUP_RAID6,
.mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
},
};
/*
* Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
* can be used as index to access btrfs_raid_array[].
*/
enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags)
{
const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK);
if (!profile)
return BTRFS_RAID_SINGLE;
return BTRFS_BG_FLAG_TO_INDEX(profile);
}
const char *btrfs_bg_type_to_raid_name(u64 flags)
{
const int index = btrfs_bg_flags_to_raid_index(flags);
if (index >= BTRFS_NR_RAID_TYPES)
return NULL;
return btrfs_raid_array[index].raid_name;
}
int btrfs_nr_parity_stripes(u64 type)
{
enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
return btrfs_raid_array[index].nparity;
}
/*
* Fill @buf with textual description of @bg_flags, no more than @size_buf
* bytes including terminating null byte.
*/
void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
{
int i;
int ret;
char *bp = buf;
u64 flags = bg_flags;
u32 size_bp = size_buf;
if (!flags) {
strcpy(bp, "NONE");
return;
}
#define DESCRIBE_FLAG(flag, desc) \
do { \
if (flags & (flag)) { \
ret = snprintf(bp, size_bp, "%s|", (desc)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
flags &= ~(flag); \
} \
} while (0)
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
btrfs_raid_array[i].raid_name);
#undef DESCRIBE_FLAG
if (flags) {
ret = snprintf(bp, size_bp, "0x%llx|", flags);
size_bp -= ret;
}
if (size_bp < size_buf)
buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
/*
* The text is trimmed, it's up to the caller to provide sufficiently
* large buffer
*/
out_overflow:;
}
static int init_first_rw_device(struct btrfs_trans_handle *trans);
static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
/*
* Device locking
* ==============
*
* There are several mutexes that protect manipulation of devices and low-level
* structures like chunks but not block groups, extents or files
*
* uuid_mutex (global lock)
* ------------------------
* protects the fs_uuids list that tracks all per-fs fs_devices, resulting from
* the SCAN_DEV ioctl registration or from mount either implicitly (the first
* device) or requested by the device= mount option
*
* the mutex can be very coarse and can cover long-running operations
*
* protects: updates to fs_devices counters like missing devices, rw devices,
* seeding, structure cloning, opening/closing devices at mount/umount time
*
* global::fs_devs - add, remove, updates to the global list
*
* does not protect: manipulation of the fs_devices::devices list in general
* but in mount context it could be used to exclude list modifications by eg.
* scan ioctl
*
* btrfs_device::name - renames (write side), read is RCU
*
* fs_devices::device_list_mutex (per-fs, with RCU)
* ------------------------------------------------
* protects updates to fs_devices::devices, ie. adding and deleting
*
* simple list traversal with read-only actions can be done with RCU protection
*
* may be used to exclude some operations from running concurrently without any
* modifications to the list (see write_all_supers)
*
* Is not required at mount and close times, because our device list is
* protected by the uuid_mutex at that point.
*
* balance_mutex
* -------------
* protects balance structures (status, state) and context accessed from
* several places (internally, ioctl)
*
* chunk_mutex
* -----------
* protects chunks, adding or removing during allocation, trim or when a new
* device is added/removed. Additionally it also protects post_commit_list of
* individual devices, since they can be added to the transaction's
* post_commit_list only with chunk_mutex held.
*
* cleaner_mutex
* -------------
* a big lock that is held by the cleaner thread and prevents running subvolume
* cleaning together with relocation or delayed iputs
*
*
* Lock nesting
* ============
*
* uuid_mutex
* device_list_mutex
* chunk_mutex
* balance_mutex
*
*
* Exclusive operations
* ====================
*
* Maintains the exclusivity of the following operations that apply to the
* whole filesystem and cannot run in parallel.
*
* - Balance (*)
* - Device add
* - Device remove
* - Device replace (*)
* - Resize
*
* The device operations (as above) can be in one of the following states:
*
* - Running state
* - Paused state
* - Completed state
*
* Only device operations marked with (*) can go into the Paused state for the
* following reasons:
*
* - ioctl (only Balance can be Paused through ioctl)
* - filesystem remounted as read-only
* - filesystem unmounted and mounted as read-only
* - system power-cycle and filesystem mounted as read-only
* - filesystem or device errors leading to forced read-only
*
* The status of exclusive operation is set and cleared atomically.
* During the course of Paused state, fs_info::exclusive_operation remains set.
* A device operation in Paused or Running state can be canceled or resumed
* either by ioctl (Balance only) or when remounted as read-write.
* The exclusive status is cleared when the device operation is canceled or
* completed.
*/
DEFINE_MUTEX(uuid_mutex);
static LIST_HEAD(fs_uuids);
struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
{
return &fs_uuids;
}
/*
* Allocate new btrfs_fs_devices structure identified by a fsid.
*
* @fsid: if not NULL, copy the UUID to fs_devices::fsid and to
* fs_devices::metadata_fsid
*
* Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
* The returned struct is not linked onto any lists and can be destroyed with
* kfree() right away.
*/
static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
{
struct btrfs_fs_devices *fs_devs;
fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
if (!fs_devs)
return ERR_PTR(-ENOMEM);
mutex_init(&fs_devs->device_list_mutex);
INIT_LIST_HEAD(&fs_devs->devices);
INIT_LIST_HEAD(&fs_devs->alloc_list);
INIT_LIST_HEAD(&fs_devs->fs_list);
INIT_LIST_HEAD(&fs_devs->seed_list);
if (fsid) {
memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
}
return fs_devs;
}
static void btrfs_free_device(struct btrfs_device *device)
{
WARN_ON(!list_empty(&device->post_commit_list));
rcu_string_free(device->name);
extent_io_tree_release(&device->alloc_state);
btrfs_destroy_dev_zone_info(device);
kfree(device);
}
static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *device;
WARN_ON(fs_devices->opened);
while (!list_empty(&fs_devices->devices)) {
device = list_entry(fs_devices->devices.next,
struct btrfs_device, dev_list);
list_del(&device->dev_list);
btrfs_free_device(device);
}
kfree(fs_devices);
}
void __exit btrfs_cleanup_fs_uuids(void)
{
struct btrfs_fs_devices *fs_devices;
while (!list_empty(&fs_uuids)) {
fs_devices = list_entry(fs_uuids.next,
struct btrfs_fs_devices, fs_list);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
static bool match_fsid_fs_devices(const struct btrfs_fs_devices *fs_devices,
const u8 *fsid, const u8 *metadata_fsid)
{
if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0)
return false;
if (!metadata_fsid)
return true;
if (memcmp(metadata_fsid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE) != 0)
return false;
return true;
}
static noinline struct btrfs_fs_devices *find_fsid(
const u8 *fsid, const u8 *metadata_fsid)
{
struct btrfs_fs_devices *fs_devices;
ASSERT(fsid);
/* Handle non-split brain cases */
list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
if (match_fsid_fs_devices(fs_devices, fsid, metadata_fsid))
return fs_devices;
}
return NULL;
}
static int
btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder,
int flush, struct file **bdev_file,
struct btrfs_super_block **disk_super)
{
struct block_device *bdev;
int ret;
*bdev_file = bdev_file_open_by_path(device_path, flags, holder, NULL);
if (IS_ERR(*bdev_file)) {
ret = PTR_ERR(*bdev_file);
goto error;
}
bdev = file_bdev(*bdev_file);
if (flush)
sync_blockdev(bdev);
if (holder) {
ret = set_blocksize(*bdev_file, BTRFS_BDEV_BLOCKSIZE);
if (ret) {
fput(*bdev_file);
goto error;
}
}
invalidate_bdev(bdev);
*disk_super = btrfs_read_dev_super(bdev);
if (IS_ERR(*disk_super)) {
ret = PTR_ERR(*disk_super);
fput(*bdev_file);
goto error;
}
return 0;
error:
*disk_super = NULL;
*bdev_file = NULL;
return ret;
}
/*
* Search and remove all stale devices (which are not mounted). When both
* inputs are NULL, it will search and release all stale devices.
*
* @devt: Optional. When provided will it release all unmounted devices
* matching this devt only.
* @skip_device: Optional. Will skip this device when searching for the stale
* devices.
*
* Return: 0 for success or if @devt is 0.
* -EBUSY if @devt is a mounted device.
* -ENOENT if @devt does not match any device in the list.
*/
static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device)
{
struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;
struct btrfs_device *device, *tmp_device;
int ret;
bool freed = false;
lockdep_assert_held(&uuid_mutex);
/* Return good status if there is no instance of devt. */
ret = 0;
list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry_safe(device, tmp_device,
&fs_devices->devices, dev_list) {
if (skip_device && skip_device == device)
continue;
if (devt && devt != device->devt)
continue;
if (fs_devices->opened) {
if (devt)
ret = -EBUSY;
break;
}
/* delete the stale device */
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
freed = true;
}
mutex_unlock(&fs_devices->device_list_mutex);
if (fs_devices->num_devices == 0) {
btrfs_sysfs_remove_fsid(fs_devices);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
/* If there is at least one freed device return 0. */
if (freed)
return 0;
return ret;
}
static struct btrfs_fs_devices *find_fsid_by_device(
struct btrfs_super_block *disk_super,
dev_t devt, bool *same_fsid_diff_dev)
{
struct btrfs_fs_devices *fsid_fs_devices;
struct btrfs_fs_devices *devt_fs_devices;
const bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
bool found_by_devt = false;
/* Find the fs_device by the usual method, if found use it. */
fsid_fs_devices = find_fsid(disk_super->fsid,
has_metadata_uuid ? disk_super->metadata_uuid : NULL);
/* The temp_fsid feature is supported only with single device filesystem. */
if (btrfs_super_num_devices(disk_super) != 1)
return fsid_fs_devices;
/*
* A seed device is an integral component of the sprout device, which
* functions as a multi-device filesystem. So, temp-fsid feature is
* not supported.
*/
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)
return fsid_fs_devices;
/* Try to find a fs_devices by matching devt. */
list_for_each_entry(devt_fs_devices, &fs_uuids, fs_list) {
struct btrfs_device *device;
list_for_each_entry(device, &devt_fs_devices->devices, dev_list) {
if (device->devt == devt) {
found_by_devt = true;
break;
}
}
if (found_by_devt)
break;
}
if (found_by_devt) {
/* Existing device. */
if (fsid_fs_devices == NULL) {
if (devt_fs_devices->opened == 0) {
/* Stale device. */
return NULL;
} else {
/* temp_fsid is mounting a subvol. */
return devt_fs_devices;
}
} else {
/* Regular or temp_fsid device mounting a subvol. */
return devt_fs_devices;
}
} else {
/* New device. */
if (fsid_fs_devices == NULL) {
return NULL;
} else {
/* sb::fsid is already used create a new temp_fsid. */
*same_fsid_diff_dev = true;
return NULL;
}
}
/* Not reached. */
}
/*
* This is only used on mount, and we are protected from competing things
* messing with our fs_devices by the uuid_mutex, thus we do not need the
* fs_devices->device_list_mutex here.
*/
static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
struct btrfs_device *device, blk_mode_t flags,
void *holder)
{
struct file *bdev_file;
struct btrfs_super_block *disk_super;
u64 devid;
int ret;
if (device->bdev)
return -EINVAL;
if (!device->name)
return -EINVAL;
ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
&bdev_file, &disk_super);
if (ret)
return ret;
devid = btrfs_stack_device_id(&disk_super->dev_item);
if (devid != device->devid)
goto error_free_page;
if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE))
goto error_free_page;
device->generation = btrfs_super_generation(disk_super);
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
if (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
pr_err(
"BTRFS: Invalid seeding and uuid-changed device detected\n");
goto error_free_page;
}
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
fs_devices->seeding = true;
} else {
if (bdev_read_only(file_bdev(bdev_file)))
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
else
set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
}
if (!bdev_nonrot(file_bdev(bdev_file)))
fs_devices->rotating = true;
if (bdev_max_discard_sectors(file_bdev(bdev_file)))
fs_devices->discardable = true;
device->bdev_file = bdev_file;
device->bdev = file_bdev(bdev_file);
clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
if (device->devt != device->bdev->bd_dev) {
btrfs_warn(NULL,
"device %s maj:min changed from %d:%d to %d:%d",
device->name->str, MAJOR(device->devt),
MINOR(device->devt), MAJOR(device->bdev->bd_dev),
MINOR(device->bdev->bd_dev));
device->devt = device->bdev->bd_dev;
}
fs_devices->open_devices++;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
device->devid != BTRFS_DEV_REPLACE_DEVID) {
fs_devices->rw_devices++;
list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
}
btrfs_release_disk_super(disk_super);
return 0;
error_free_page:
btrfs_release_disk_super(disk_super);
fput(bdev_file);
return -EINVAL;
}
const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb)
{
bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
}
/*
* Add new device to list of registered devices
*
* Returns:
* device pointer which was just added or updated when successful
* error pointer when failed
*/
static noinline struct btrfs_device *device_list_add(const char *path,
struct btrfs_super_block *disk_super,
bool *new_device_added)
{
struct btrfs_device *device;
struct btrfs_fs_devices *fs_devices = NULL;
struct rcu_string *name;
u64 found_transid = btrfs_super_generation(disk_super);
u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
dev_t path_devt;
int error;
bool same_fsid_diff_dev = false;
bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
btrfs_err(NULL,
"device %s has incomplete metadata_uuid change, please use btrfstune to complete",
path);
return ERR_PTR(-EAGAIN);
}
error = lookup_bdev(path, &path_devt);
if (error) {
btrfs_err(NULL, "failed to lookup block device for path %s: %d",
path, error);
return ERR_PTR(error);
}
fs_devices = find_fsid_by_device(disk_super, path_devt, &same_fsid_diff_dev);
if (!fs_devices) {
fs_devices = alloc_fs_devices(disk_super->fsid);
if (IS_ERR(fs_devices))
return ERR_CAST(fs_devices);
if (has_metadata_uuid)
memcpy(fs_devices->metadata_uuid,
disk_super->metadata_uuid, BTRFS_FSID_SIZE);
if (same_fsid_diff_dev) {
generate_random_uuid(fs_devices->fsid);
fs_devices->temp_fsid = true;
pr_info("BTRFS: device %s (%d:%d) using temp-fsid %pU\n",
path, MAJOR(path_devt), MINOR(path_devt),
fs_devices->fsid);
}
mutex_lock(&fs_devices->device_list_mutex);
list_add(&fs_devices->fs_list, &fs_uuids);
device = NULL;
} else {
struct btrfs_dev_lookup_args args = {
.devid = devid,
.uuid = disk_super->dev_item.uuid,
};
mutex_lock(&fs_devices->device_list_mutex);
device = btrfs_find_device(fs_devices, &args);
if (found_transid > fs_devices->latest_generation) {
memcpy(fs_devices->fsid, disk_super->fsid,
BTRFS_FSID_SIZE);
memcpy(fs_devices->metadata_uuid,
btrfs_sb_fsid_ptr(disk_super), BTRFS_FSID_SIZE);
}
}
if (!device) {
unsigned int nofs_flag;
if (fs_devices->opened) {
btrfs_err(NULL,
"device %s (%d:%d) belongs to fsid %pU, and the fs is already mounted, scanned by %s (%d)",
path, MAJOR(path_devt), MINOR(path_devt),
fs_devices->fsid, current->comm,
task_pid_nr(current));
mutex_unlock(&fs_devices->device_list_mutex);
return ERR_PTR(-EBUSY);
}
nofs_flag = memalloc_nofs_save();
device = btrfs_alloc_device(NULL, &devid,
disk_super->dev_item.uuid, path);
memalloc_nofs_restore(nofs_flag);
if (IS_ERR(device)) {
mutex_unlock(&fs_devices->device_list_mutex);
/* we can safely leave the fs_devices entry around */
return device;
}
device->devt = path_devt;
list_add_rcu(&device->dev_list, &fs_devices->devices);
fs_devices->num_devices++;
device->fs_devices = fs_devices;
*new_device_added = true;
if (disk_super->label[0])
pr_info(
"BTRFS: device label %s devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
disk_super->label, devid, found_transid, path,
MAJOR(path_devt), MINOR(path_devt),
current->comm, task_pid_nr(current));
else
pr_info(
"BTRFS: device fsid %pU devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
disk_super->fsid, devid, found_transid, path,
MAJOR(path_devt), MINOR(path_devt),
current->comm, task_pid_nr(current));
} else if (!device->name || strcmp(device->name->str, path)) {
/*
* When FS is already mounted.
* 1. If you are here and if the device->name is NULL that
* means this device was missing at time of FS mount.
* 2. If you are here and if the device->name is different
* from 'path' that means either
* a. The same device disappeared and reappeared with
* different name. or
* b. The missing-disk-which-was-replaced, has
* reappeared now.
*
* We must allow 1 and 2a above. But 2b would be a spurious
* and unintentional.
*
* Further in case of 1 and 2a above, the disk at 'path'
* would have missed some transaction when it was away and
* in case of 2a the stale bdev has to be updated as well.
* 2b must not be allowed at all time.
*/
/*
* For now, we do allow update to btrfs_fs_device through the
* btrfs dev scan cli after FS has been mounted. We're still
* tracking a problem where systems fail mount by subvolume id
* when we reject replacement on a mounted FS.
*/
if (!fs_devices->opened && found_transid < device->generation) {
/*
* That is if the FS is _not_ mounted and if you
* are here, that means there is more than one
* disk with same uuid and devid.We keep the one
* with larger generation number or the last-in if
* generation are equal.
*/
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_err(NULL,
"device %s already registered with a higher generation, found %llu expect %llu",
path, found_transid, device->generation);
return ERR_PTR(-EEXIST);
}
/*
* We are going to replace the device path for a given devid,
* make sure it's the same device if the device is mounted
*
* NOTE: the device->fs_info may not be reliable here so pass
* in a NULL to message helpers instead. This avoids a possible
* use-after-free when the fs_info and fs_info->sb are already
* torn down.
*/
if (device->bdev) {
if (device->devt != path_devt) {
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_warn_in_rcu(NULL,
"duplicate device %s devid %llu generation %llu scanned by %s (%d)",
path, devid, found_transid,
current->comm,
task_pid_nr(current));
return ERR_PTR(-EEXIST);
}
btrfs_info_in_rcu(NULL,
"devid %llu device path %s changed to %s scanned by %s (%d)",
devid, btrfs_dev_name(device),
path, current->comm,
task_pid_nr(current));
}
name = rcu_string_strdup(path, GFP_NOFS);
if (!name) {
mutex_unlock(&fs_devices->device_list_mutex);
return ERR_PTR(-ENOMEM);
}
rcu_string_free(device->name);
rcu_assign_pointer(device->name, name);
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
fs_devices->missing_devices--;
clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
}
device->devt = path_devt;
}
/*
* Unmount does not free the btrfs_device struct but would zero
* generation along with most of the other members. So just update
* it back. We need it to pick the disk with largest generation
* (as above).
*/
if (!fs_devices->opened) {
device->generation = found_transid;
fs_devices->latest_generation = max_t(u64, found_transid,
fs_devices->latest_generation);
}
fs_devices->total_devices = btrfs_super_num_devices(disk_super);
mutex_unlock(&fs_devices->device_list_mutex);
return device;
}
static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
{
struct btrfs_fs_devices *fs_devices;
struct btrfs_device *device;
struct btrfs_device *orig_dev;
int ret = 0;
lockdep_assert_held(&uuid_mutex);
fs_devices = alloc_fs_devices(orig->fsid);
if (IS_ERR(fs_devices))
return fs_devices;
fs_devices->total_devices = orig->total_devices;
list_for_each_entry(orig_dev, &orig->devices, dev_list) {
const char *dev_path = NULL;
/*
* This is ok to do without RCU read locked because we hold the
* uuid mutex so nothing we touch in here is going to disappear.
*/
if (orig_dev->name)
dev_path = orig_dev->name->str;
device = btrfs_alloc_device(NULL, &orig_dev->devid,
orig_dev->uuid, dev_path);
if (IS_ERR(device)) {
ret = PTR_ERR(device);
goto error;
}
if (orig_dev->zone_info) {
struct btrfs_zoned_device_info *zone_info;
zone_info = btrfs_clone_dev_zone_info(orig_dev);
if (!zone_info) {
btrfs_free_device(device);
ret = -ENOMEM;
goto error;
}
device->zone_info = zone_info;
}
list_add(&device->dev_list, &fs_devices->devices);
device->fs_devices = fs_devices;
fs_devices->num_devices++;
}
return fs_devices;
error:
free_fs_devices(fs_devices);
return ERR_PTR(ret);
}
static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
struct btrfs_device **latest_dev)
{
struct btrfs_device *device, *next;
/* This is the initialized path, it is safe to release the devices. */
list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) {
if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
&device->dev_state) &&
!test_bit(BTRFS_DEV_STATE_MISSING,
&device->dev_state) &&
(!*latest_dev ||
device->generation > (*latest_dev)->generation)) {
*latest_dev = device;
}
continue;
}
/*
* We have already validated the presence of BTRFS_DEV_REPLACE_DEVID,
* in btrfs_init_dev_replace() so just continue.
*/
if (device->devid == BTRFS_DEV_REPLACE_DEVID)
continue;
if (device->bdev_file) {
fput(device->bdev_file);
device->bdev = NULL;
device->bdev_file = NULL;
fs_devices->open_devices--;
}
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
list_del_init(&device->dev_alloc_list);
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
fs_devices->rw_devices--;
}
list_del_init(&device->dev_list);
fs_devices->num_devices--;
btrfs_free_device(device);
}
}
/*
* After we have read the system tree and know devids belonging to this
* filesystem, remove the device which does not belong there.
*/
void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *latest_dev = NULL;
struct btrfs_fs_devices *seed_dev;
mutex_lock(&uuid_mutex);
__btrfs_free_extra_devids(fs_devices, &latest_dev);
list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)
__btrfs_free_extra_devids(seed_dev, &latest_dev);
fs_devices->latest_dev = latest_dev;
mutex_unlock(&uuid_mutex);
}
static void btrfs_close_bdev(struct btrfs_device *device)
{
if (!device->bdev)
return;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
sync_blockdev(device->bdev);
invalidate_bdev(device->bdev);
}
fput(device->bdev_file);
}
static void btrfs_close_one_device(struct btrfs_device *device)
{
struct btrfs_fs_devices *fs_devices = device->fs_devices;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
device->devid != BTRFS_DEV_REPLACE_DEVID) {
list_del_init(&device->dev_alloc_list);
fs_devices->rw_devices--;
}
if (device->devid == BTRFS_DEV_REPLACE_DEVID)
clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
fs_devices->missing_devices--;
}
btrfs_close_bdev(device);
if (device->bdev) {
fs_devices->open_devices--;
device->bdev = NULL;
}
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
btrfs_destroy_dev_zone_info(device);
device->fs_info = NULL;
atomic_set(&device->dev_stats_ccnt, 0);
extent_io_tree_release(&device->alloc_state);
/*
* Reset the flush error record. We might have a transient flush error
* in this mount, and if so we aborted the current transaction and set
* the fs to an error state, guaranteeing no super blocks can be further
* committed. However that error might be transient and if we unmount the
* filesystem and mount it again, we should allow the mount to succeed
* (btrfs_check_rw_degradable() should not fail) - if after mounting the
* filesystem again we still get flush errors, then we will again abort
* any transaction and set the error state, guaranteeing no commits of
* unsafe super blocks.
*/
device->last_flush_error = 0;
/* Verify the device is back in a pristine state */
WARN_ON(test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state));
WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state));
WARN_ON(!list_empty(&device->dev_alloc_list));
WARN_ON(!list_empty(&device->post_commit_list));
}
static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *device, *tmp;
lockdep_assert_held(&uuid_mutex);
if (--fs_devices->opened > 0)
return;
list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
btrfs_close_one_device(device);
WARN_ON(fs_devices->open_devices);
WARN_ON(fs_devices->rw_devices);
fs_devices->opened = 0;
fs_devices->seeding = false;
fs_devices->fs_info = NULL;
}
void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
LIST_HEAD(list);
struct btrfs_fs_devices *tmp;
mutex_lock(&uuid_mutex);
close_fs_devices(fs_devices);
if (!fs_devices->opened) {
list_splice_init(&fs_devices->seed_list, &list);
/*
* If the struct btrfs_fs_devices is not assembled with any
* other device, it can be re-initialized during the next mount
* without the needing device-scan step. Therefore, it can be
* fully freed.
*/
if (fs_devices->num_devices == 1) {
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {
close_fs_devices(fs_devices);
list_del(&fs_devices->seed_list);
free_fs_devices(fs_devices);
}
mutex_unlock(&uuid_mutex);
}
static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
blk_mode_t flags, void *holder)
{
struct btrfs_device *device;
struct btrfs_device *latest_dev = NULL;
struct btrfs_device *tmp_device;
int ret = 0;
list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
dev_list) {
int ret2;
ret2 = btrfs_open_one_device(fs_devices, device, flags, holder);
if (ret2 == 0 &&
(!latest_dev || device->generation > latest_dev->generation)) {
latest_dev = device;
} else if (ret2 == -ENODATA) {
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
}
if (ret == 0 && ret2 != 0)
ret = ret2;
}
if (fs_devices->open_devices == 0) {
if (ret)
return ret;
return -EINVAL;
}
fs_devices->opened = 1;
fs_devices->latest_dev = latest_dev;
fs_devices->total_rw_bytes = 0;
fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
fs_devices->read_policy = BTRFS_READ_POLICY_PID;
return 0;
}
static int devid_cmp(void *priv, const struct list_head *a,
const struct list_head *b)
{
const struct btrfs_device *dev1, *dev2;
dev1 = list_entry(a, struct btrfs_device, dev_list);
dev2 = list_entry(b, struct btrfs_device, dev_list);
if (dev1->devid < dev2->devid)
return -1;
else if (dev1->devid > dev2->devid)
return 1;
return 0;
}
int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
blk_mode_t flags, void *holder)
{
int ret;
lockdep_assert_held(&uuid_mutex);
/*
* The device_list_mutex cannot be taken here in case opening the
* underlying device takes further locks like open_mutex.
*
* We also don't need the lock here as this is called during mount and
* exclusion is provided by uuid_mutex
*/
if (fs_devices->opened) {
fs_devices->opened++;
ret = 0;
} else {
list_sort(NULL, &fs_devices->devices, devid_cmp);
ret = open_fs_devices(fs_devices, flags, holder);
}
return ret;
}
void btrfs_release_disk_super(struct btrfs_super_block *super)
{
struct page *page = virt_to_page(super);
put_page(page);
}
static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
u64 bytenr, u64 bytenr_orig)
{
struct btrfs_super_block *disk_super;
struct page *page;
void *p;
pgoff_t index;
/* make sure our super fits in the device */
if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev))
return ERR_PTR(-EINVAL);
/* make sure our super fits in the page */
if (sizeof(*disk_super) > PAGE_SIZE)
return ERR_PTR(-EINVAL);
/* make sure our super doesn't straddle pages on disk */
index = bytenr >> PAGE_SHIFT;
if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
return ERR_PTR(-EINVAL);
/* pull in the page with our super */
page = read_cache_page_gfp(bdev->bd_mapping, index, GFP_KERNEL);
if (IS_ERR(page))
return ERR_CAST(page);
p = page_address(page);
/* align our pointer to the offset of the super block */
disk_super = p + offset_in_page(bytenr);
if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
btrfs_release_disk_super(p);
return ERR_PTR(-EINVAL);
}
if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
return disk_super;
}
int btrfs_forget_devices(dev_t devt)
{
int ret;
mutex_lock(&uuid_mutex);
ret = btrfs_free_stale_devices(devt, NULL);
mutex_unlock(&uuid_mutex);
return ret;
}
static bool btrfs_skip_registration(struct btrfs_super_block *disk_super,
const char *path, dev_t devt,
bool mount_arg_dev)
{
struct btrfs_fs_devices *fs_devices;
/*
* Do not skip device registration for mounted devices with matching
* maj:min but different paths. Booting without initrd relies on
* /dev/root initially, later replaced with the actual root device.
* A successful scan ensures grub2-probe selects the correct device.
*/
list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
struct btrfs_device *device;
mutex_lock(&fs_devices->device_list_mutex);
if (!fs_devices->opened) {
mutex_unlock(&fs_devices->device_list_mutex);
continue;
}
list_for_each_entry(device, &fs_devices->devices, dev_list) {
if (device->bdev && (device->bdev->bd_dev == devt) &&
strcmp(device->name->str, path) != 0) {
mutex_unlock(&fs_devices->device_list_mutex);
/* Do not skip registration. */
return false;
}
}
mutex_unlock(&fs_devices->device_list_mutex);
}
if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&
!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING))
return true;
return false;
}
/*
* Look for a btrfs signature on a device. This may be called out of the mount path
* and we are not allowed to call set_blocksize during the scan. The superblock
* is read via pagecache.
*
* With @mount_arg_dev it's a scan during mount time that will always register
* the device or return an error. Multi-device and seeding devices are registered
* in both cases.
*/
struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
bool mount_arg_dev)
{
struct btrfs_super_block *disk_super;
bool new_device_added = false;
struct btrfs_device *device = NULL;
struct file *bdev_file;
u64 bytenr;
dev_t devt;
int ret;
lockdep_assert_held(&uuid_mutex);
/*
* Avoid an exclusive open here, as the systemd-udev may initiate the
* device scan which may race with the user's mount or mkfs command,
* resulting in failure.
* Since the device scan is solely for reading purposes, there is no
* need for an exclusive open. Additionally, the devices are read again
* during the mount process. It is ok to get some inconsistent
* values temporarily, as the device paths of the fsid are the only
* required information for assembling the volume.
*/
bdev_file = bdev_file_open_by_path(path, flags, NULL, NULL);
if (IS_ERR(bdev_file))
return ERR_CAST(bdev_file);
/*
* We would like to check all the super blocks, but doing so would
* allow a mount to succeed after a mkfs from a different filesystem.
* Currently, recovery from a bad primary btrfs superblock is done
* using the userspace command 'btrfs check --super'.
*/
ret = btrfs_sb_log_location_bdev(file_bdev(bdev_file), 0, READ, &bytenr);
if (ret) {
device = ERR_PTR(ret);
goto error_bdev_put;
}
disk_super = btrfs_read_disk_super(file_bdev(bdev_file), bytenr,
btrfs_sb_offset(0));
if (IS_ERR(disk_super)) {
device = ERR_CAST(disk_super);
goto error_bdev_put;
}
devt = file_bdev(bdev_file)->bd_dev;
if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) {
pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",
path, MAJOR(devt), MINOR(devt));
btrfs_free_stale_devices(devt, NULL);
device = NULL;
goto free_disk_super;
}
device = device_list_add(path, disk_super, &new_device_added);
if (!IS_ERR(device) && new_device_added)
btrfs_free_stale_devices(device->devt, device);
free_disk_super:
btrfs_release_disk_super(disk_super);
error_bdev_put:
fput(bdev_file);
return device;
}
/*
* Try to find a chunk that intersects [start, start + len] range and when one
* such is found, record the end of it in *start
*/
static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
u64 len)
{
u64 physical_start, physical_end;
lockdep_assert_held(&device->fs_info->chunk_mutex);
if (find_first_extent_bit(&device->alloc_state, *start,
&physical_start, &physical_end,
CHUNK_ALLOCATED, NULL)) {
if (in_range(physical_start, *start, len) ||
in_range(*start, physical_start,
physical_end + 1 - physical_start)) {
*start = physical_end + 1;
return true;
}
}
return false;
}
static u64 dev_extent_search_start(struct btrfs_device *device)
{
switch (device->fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
return BTRFS_DEVICE_RANGE_RESERVED;
case BTRFS_CHUNK_ALLOC_ZONED:
/*
* We don't care about the starting region like regular
* allocator, because we anyway use/reserve the first two zones
* for superblock logging.
*/
return 0;
default:
BUG();
}
}
static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
u64 *hole_start, u64 *hole_size,
u64 num_bytes)
{
u64 zone_size = device->zone_info->zone_size;
u64 pos;
int ret;
bool changed = false;
ASSERT(IS_ALIGNED(*hole_start, zone_size));
while (*hole_size > 0) {
pos = btrfs_find_allocatable_zones(device, *hole_start,
*hole_start + *hole_size,
num_bytes);
if (pos != *hole_start) {
*hole_size = *hole_start + *hole_size - pos;
*hole_start = pos;
changed = true;
if (*hole_size < num_bytes)
break;
}
ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
/* Range is ensured to be empty */
if (!ret)
return changed;
/* Given hole range was invalid (outside of device) */
if (ret == -ERANGE) {
*hole_start += *hole_size;
*hole_size = 0;
return true;
}
*hole_start += zone_size;
*hole_size -= zone_size;
changed = true;
}
return changed;
}
/*
* Check if specified hole is suitable for allocation.
*
* @device: the device which we have the hole
* @hole_start: starting position of the hole
* @hole_size: the size of the hole
* @num_bytes: the size of the free space that we need
*
* This function may modify @hole_start and @hole_size to reflect the suitable
* position for allocation. Returns 1 if hole position is updated, 0 otherwise.
*/
static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
u64 *hole_size, u64 num_bytes)
{
bool changed = false;
u64 hole_end = *hole_start + *hole_size;
for (;;) {
/*
* Check before we set max_hole_start, otherwise we could end up
* sending back this offset anyway.
*/
if (contains_pending_extent(device, hole_start, *hole_size)) {
if (hole_end >= *hole_start)
*hole_size = hole_end - *hole_start;
else
*hole_size = 0;
changed = true;
}
switch (device->fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
/* No extra check */
break;
case BTRFS_CHUNK_ALLOC_ZONED:
if (dev_extent_hole_check_zoned(device, hole_start,
hole_size, num_bytes)) {
changed = true;
/*
* The changed hole can contain pending extent.
* Loop again to check that.
*/
continue;
}
break;
default:
BUG();
}
break;
}
return changed;
}
/*
* Find free space in the specified device.
*
* @device: the device which we search the free space in
* @num_bytes: the size of the free space that we need
* @search_start: the position from which to begin the search
* @start: store the start of the free space.
* @len: the size of the free space. that we find, or the size
* of the max free space if we don't find suitable free space
*
* This does a pretty simple search, the expectation is that it is called very
* infrequently and that a given device has a small number of extents.
*
* @start is used to store the start of the free space if we find. But if we
* don't find suitable free space, it will be used to store the start position
* of the max free space.
*
* @len is used to store the size of the free space that we find.
* But if we don't find suitable free space, it is used to store the size of
* the max free space.
*
* NOTE: This function will search *commit* root of device tree, and does extra
* check to ensure dev extents are not double allocated.
* This makes the function safe to allocate dev extents but may not report
* correct usable device space, as device extent freed in current transaction
* is not reported as available.
*/
static int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
u64 *start, u64 *len)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_key key;
struct btrfs_dev_extent *dev_extent;
struct btrfs_path *path;
u64 search_start;
u64 hole_size;
u64 max_hole_start;
u64 max_hole_size = 0;
u64 extent_end;
u64 search_end = device->total_bytes;
int ret;
int slot;
struct extent_buffer *l;
search_start = dev_extent_search_start(device);
max_hole_start = search_start;
WARN_ON(device->zone_info &&
!IS_ALIGNED(num_bytes, device->zone_info->zone_size));
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
again:
if (search_start >= search_end ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
ret = -ENOSPC;
goto out;
}
path->reada = READA_FORWARD;
path->search_commit_root = 1;
path->skip_locking = 1;
key.objectid = device->devid;
key.offset = search_start;
key.type = BTRFS_DEV_EXTENT_KEY;
ret = btrfs_search_backwards(root, &key, path);
if (ret < 0)
goto out;
while (search_start < search_end) {
l = path->nodes[0];
slot = path->slots[0];
if (slot >= btrfs_header_nritems(l)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto out;
break;
}
btrfs_item_key_to_cpu(l, &key, slot);
if (key.objectid < device->devid)
goto next;
if (key.objectid > device->devid)
break;
if (key.type != BTRFS_DEV_EXTENT_KEY)
goto next;
if (key.offset > search_end)
break;
if (key.offset > search_start) {
hole_size = key.offset - search_start;
dev_extent_hole_check(device, &search_start, &hole_size,
num_bytes);
if (hole_size > max_hole_size) {
max_hole_start = search_start;
max_hole_size = hole_size;
}
/*
* If this free space is greater than which we need,
* it must be the max free space that we have found
* until now, so max_hole_start must point to the start
* of this free space and the length of this free space
* is stored in max_hole_size. Thus, we return
* max_hole_start and max_hole_size and go back to the
* caller.
*/
if (hole_size >= num_bytes) {
ret = 0;
goto out;
}
}
dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
extent_end = key.offset + btrfs_dev_extent_length(l,
dev_extent);
if (extent_end > search_start)
search_start = extent_end;
next:
path->slots[0]++;
cond_resched();
}
/*
* At this point, search_start should be the end of
* allocated dev extents, and when shrinking the device,
* search_end may be smaller than search_start.
*/
if (search_end > search_start) {
hole_size = search_end - search_start;
if (dev_extent_hole_check(device, &search_start, &hole_size,
num_bytes)) {
btrfs_release_path(path);
goto again;
}
if (hole_size > max_hole_size) {
max_hole_start = search_start;
max_hole_size = hole_size;
}
}
/* See above. */
if (max_hole_size < num_bytes)
ret = -ENOSPC;
else
ret = 0;
ASSERT(max_hole_start + max_hole_size <= search_end);
out:
btrfs_free_path(path);
*start = max_hole_start;
if (len)
*len = max_hole_size;
return ret;
}
static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
struct btrfs_device *device,
u64 start, u64 *dev_extent_len)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_root *root = fs_info->dev_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_key found_key;
struct extent_buffer *leaf = NULL;
struct btrfs_dev_extent *extent = NULL;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = device->devid;
key.offset = start;
key.type = BTRFS_DEV_EXTENT_KEY;
again:
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = btrfs_previous_item(root, path, key.objectid,
BTRFS_DEV_EXTENT_KEY);
if (ret)
goto out;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
extent = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_extent);
BUG_ON(found_key.offset > start || found_key.offset +
btrfs_dev_extent_length(leaf, extent) < start);
key = found_key;
btrfs_release_path(path);
goto again;
} else if (ret == 0) {
leaf = path->nodes[0];
extent = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_extent);
} else {
goto out;
}
*dev_extent_len = btrfs_dev_extent_length(leaf, extent);
ret = btrfs_del_item(trans, root, path);
if (ret == 0)
set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
out:
btrfs_free_path(path);
return ret;
}
static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
{
struct rb_node *n;
u64 ret = 0;
read_lock(&fs_info->mapping_tree_lock);
n = rb_last(&fs_info->mapping_tree.rb_root);
if (n) {
struct btrfs_chunk_map *map;
map = rb_entry(n, struct btrfs_chunk_map, rb_node);
ret = map->start + map->chunk_len;
}
read_unlock(&fs_info->mapping_tree_lock);
return ret;
}
static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
u64 *devid_ret)
{
int ret;
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_path *path;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
if (ret < 0)
goto error;
if (ret == 0) {
/* Corruption */
btrfs_err(fs_info, "corrupted chunk tree devid -1 matched");
ret = -EUCLEAN;
goto error;
}
ret = btrfs_previous_item(fs_info->chunk_root, path,
BTRFS_DEV_ITEMS_OBJECTID,
BTRFS_DEV_ITEM_KEY);
if (ret) {
*devid_ret = 1;
} else {
btrfs_item_key_to_cpu(path->nodes[0], &found_key,
path->slots[0]);
*devid_ret = found_key.offset + 1;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
/*
* the device information is stored in the chunk root
* the btrfs_device struct should be fully filled in
*/
static int btrfs_add_dev_item(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
int ret;
struct btrfs_path *path;
struct btrfs_dev_item *dev_item;
struct extent_buffer *leaf;
struct btrfs_key key;
unsigned long ptr;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
btrfs_reserve_chunk_metadata(trans, true);
ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path,
&key, sizeof(*dev_item));
btrfs_trans_release_chunk_metadata(trans);
if (ret)
goto out;
leaf = path->nodes[0];
dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
btrfs_set_device_id(leaf, dev_item, device->devid);
btrfs_set_device_generation(leaf, dev_item, 0);
btrfs_set_device_type(leaf, dev_item, device->type);
btrfs_set_device_io_align(leaf, dev_item, device->io_align);
btrfs_set_device_io_width(leaf, dev_item, device->io_width);
btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
btrfs_set_device_total_bytes(leaf, dev_item,
btrfs_device_get_disk_total_bytes(device));
btrfs_set_device_bytes_used(leaf, dev_item,
btrfs_device_get_bytes_used(device));
btrfs_set_device_group(leaf, dev_item, 0);
btrfs_set_device_seek_speed(leaf, dev_item, 0);
btrfs_set_device_bandwidth(leaf, dev_item, 0);
btrfs_set_device_start_offset(leaf, dev_item, 0);
ptr = btrfs_device_uuid(dev_item);
write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
ptr = btrfs_device_fsid(dev_item);
write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid,
ptr, BTRFS_FSID_SIZE);
btrfs_mark_buffer_dirty(trans, leaf);
ret = 0;
out:
btrfs_free_path(path);
return ret;
}
/*
* Function to update ctime/mtime for a given device path.
* Mainly used for ctime/mtime based probe like libblkid.
*
* We don't care about errors here, this is just to be kind to userspace.
*/
static void update_dev_time(const char *device_path)
{
struct path path;
int ret;
ret = kern_path(device_path, LOOKUP_FOLLOW, &path);
if (ret)
return;
inode_update_time(d_inode(path.dentry), S_MTIME | S_CTIME | S_VERSION);
path_put(&path);
}
static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
struct btrfs_root *root = device->fs_info->chunk_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
btrfs_trans_release_chunk_metadata(trans);
if (ret) {
if (ret > 0)
ret = -ENOENT;
goto out;
}
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
return ret;
}
/*
* Verify that @num_devices satisfies the RAID profile constraints in the whole
* filesystem. It's up to the caller to adjust that number regarding eg. device
* replace.
*/
static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
u64 num_devices)
{
u64 all_avail;
unsigned seq;
int i;
do {
seq = read_seqbegin(&fs_info->profiles_lock);
all_avail = fs_info->avail_data_alloc_bits |
fs_info->avail_system_alloc_bits |
fs_info->avail_metadata_alloc_bits;
} while (read_seqretry(&fs_info->profiles_lock, seq));
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
if (!(all_avail & btrfs_raid_array[i].bg_flag))
continue;
if (num_devices < btrfs_raid_array[i].devs_min)
return btrfs_raid_array[i].mindev_error;
}
return 0;
}
static struct btrfs_device * btrfs_find_next_active_device(
struct btrfs_fs_devices *fs_devs, struct btrfs_device *device)
{
struct btrfs_device *next_device;
list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
if (next_device != device &&
!test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state)
&& next_device->bdev)
return next_device;
}
return NULL;
}
/*
* Helper function to check if the given device is part of s_bdev / latest_dev
* and replace it with the provided or the next active device, in the context
* where this function called, there should be always be another device (or
* this_dev) which is active.
*/
void __cold btrfs_assign_next_active_device(struct btrfs_device *device,
struct btrfs_device *next_device)
{
struct btrfs_fs_info *fs_info = device->fs_info;
if (!next_device)
next_device = btrfs_find_next_active_device(fs_info->fs_devices,
device);
ASSERT(next_device);
if (fs_info->sb->s_bdev &&
(fs_info->sb->s_bdev == device->bdev))
fs_info->sb->s_bdev = next_device->bdev;
if (fs_info->fs_devices->latest_dev->bdev == device->bdev)
fs_info->fs_devices->latest_dev = next_device;
}
/*
* Return btrfs_fs_devices::num_devices excluding the device that's being
* currently replaced.
*/
static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info)
{
u64 num_devices = fs_info->fs_devices->num_devices;
down_read(&fs_info->dev_replace.rwsem);
if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
ASSERT(num_devices > 1);
num_devices--;
}
up_read(&fs_info->dev_replace.rwsem);
return num_devices;
}
static void btrfs_scratch_superblock(struct btrfs_fs_info *fs_info,
struct block_device *bdev, int copy_num)
{
struct btrfs_super_block *disk_super;
const size_t len = sizeof(disk_super->magic);
const u64 bytenr = btrfs_sb_offset(copy_num);
int ret;
disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr);
if (IS_ERR(disk_super))
return;
memset(&disk_super->magic, 0, len);
folio_mark_dirty(virt_to_folio(disk_super));
btrfs_release_disk_super(disk_super);
ret = sync_blockdev_range(bdev, bytenr, bytenr + len - 1);
if (ret)
btrfs_warn(fs_info, "error clearing superblock number %d (%d)",
copy_num, ret);
}
void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device)
{
int copy_num;
struct block_device *bdev = device->bdev;
if (!bdev)
return;
for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) {
if (bdev_is_zoned(bdev))
btrfs_reset_sb_log_zones(bdev, copy_num);
else
btrfs_scratch_superblock(fs_info, bdev, copy_num);
}
/* Notify udev that device has changed */
btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
/* Update ctime/mtime for device path for libblkid */
update_dev_time(device->name->str);
}
int btrfs_rm_device(struct btrfs_fs_info *fs_info,
struct btrfs_dev_lookup_args *args,
struct file **bdev_file)
{
struct btrfs_trans_handle *trans;
struct btrfs_device *device;
struct btrfs_fs_devices *cur_devices;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
u64 num_devices;
int ret = 0;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info, "device remove not supported on extent tree v2 yet");
return -EINVAL;
}
/*
* The device list in fs_devices is accessed without locks (neither
* uuid_mutex nor device_list_mutex) as it won't change on a mounted
* filesystem and another device rm cannot run.
*/
num_devices = btrfs_num_devices(fs_info);
ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1);
if (ret)
return ret;
device = btrfs_find_device(fs_info->fs_devices, args);
if (!device) {
if (args->missing)
ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
else
ret = -ENOENT;
return ret;
}
if (btrfs_pinned_by_swapfile(fs_info, device)) {
btrfs_warn_in_rcu(fs_info,
"cannot remove device %s (devid %llu) due to active swapfile",
btrfs_dev_name(device), device->devid);
return -ETXTBSY;
}
if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
return BTRFS_ERROR_DEV_TGT_REPLACE;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
fs_info->fs_devices->rw_devices == 1)
return BTRFS_ERROR_DEV_ONLY_WRITABLE;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
mutex_lock(&fs_info->chunk_mutex);
list_del_init(&device->dev_alloc_list);
device->fs_devices->rw_devices--;
mutex_unlock(&fs_info->chunk_mutex);
}
ret = btrfs_shrink_device(device, 0);
if (ret)
goto error_undo;
trans = btrfs_start_transaction(fs_info->chunk_root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto error_undo;
}
ret = btrfs_rm_dev_item(trans, device);
if (ret) {
/* Any error in dev item removal is critical */
btrfs_crit(fs_info,
"failed to remove device item for devid %llu: %d",
device->devid, ret);
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
return ret;
}
clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
btrfs_scrub_cancel_dev(device);
/*
* the device list mutex makes sure that we don't change
* the device list while someone else is writing out all
* the device supers. Whoever is writing all supers, should
* lock the device list mutex before getting the number of
* devices in the super block (super_copy). Conversely,
* whoever updates the number of devices in the super block
* (super_copy) should hold the device list mutex.
*/
/*
* In normal cases the cur_devices == fs_devices. But in case
* of deleting a seed device, the cur_devices should point to
* its own fs_devices listed under the fs_devices->seed_list.
*/
cur_devices = device->fs_devices;
mutex_lock(&fs_devices->device_list_mutex);
list_del_rcu(&device->dev_list);
cur_devices->num_devices--;
cur_devices->total_devices--;
/* Update total_devices of the parent fs_devices if it's seed */
if (cur_devices != fs_devices)
fs_devices->total_devices--;
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
cur_devices->missing_devices--;
btrfs_assign_next_active_device(device, NULL);
if (device->bdev_file) {
cur_devices->open_devices--;
/* remove sysfs entry */
btrfs_sysfs_remove_device(device);
}
num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1;
btrfs_set_super_num_devices(fs_info->super_copy, num_devices);
mutex_unlock(&fs_devices->device_list_mutex);
/*
* At this point, the device is zero sized and detached from the
* devices list. All that's left is to zero out the old supers and
* free the device.
*
* We cannot call btrfs_close_bdev() here because we're holding the sb
* write lock, and fput() on the block device will pull in the
* ->open_mutex on the block device and it's dependencies. Instead
* just flush the device and let the caller do the final bdev_release.
*/
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
btrfs_scratch_superblocks(fs_info, device);
if (device->bdev) {
sync_blockdev(device->bdev);
invalidate_bdev(device->bdev);
}
}
*bdev_file = device->bdev_file;
synchronize_rcu();
btrfs_free_device(device);
/*
* This can happen if cur_devices is the private seed devices list. We
* cannot call close_fs_devices() here because it expects the uuid_mutex
* to be held, but in fact we don't need that for the private
* seed_devices, we can simply decrement cur_devices->opened and then
* remove it from our list and free the fs_devices.
*/
if (cur_devices->num_devices == 0) {
list_del_init(&cur_devices->seed_list);
ASSERT(cur_devices->opened == 1);
cur_devices->opened--;
free_fs_devices(cur_devices);
}
ret = btrfs_commit_transaction(trans);
return ret;
error_undo:
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
mutex_lock(&fs_info->chunk_mutex);
list_add(&device->dev_alloc_list,
&fs_devices->alloc_list);
device->fs_devices->rw_devices++;
mutex_unlock(&fs_info->chunk_mutex);
}
return ret;
}
void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev)
{
struct btrfs_fs_devices *fs_devices;
lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex);
/*
* in case of fs with no seed, srcdev->fs_devices will point
* to fs_devices of fs_info. However when the dev being replaced is
* a seed dev it will point to the seed's local fs_devices. In short
* srcdev will have its correct fs_devices in both the cases.
*/
fs_devices = srcdev->fs_devices;
list_del_rcu(&srcdev->dev_list);
list_del(&srcdev->dev_alloc_list);
fs_devices->num_devices--;
if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state))
fs_devices->missing_devices--;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state))
fs_devices->rw_devices--;
if (srcdev->bdev)
fs_devices->open_devices--;
}
void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev)
{
struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
mutex_lock(&uuid_mutex);
btrfs_close_bdev(srcdev);
synchronize_rcu();
btrfs_free_device(srcdev);
/* if this is no devs we rather delete the fs_devices */
if (!fs_devices->num_devices) {
/*
* On a mounted FS, num_devices can't be zero unless it's a
* seed. In case of a seed device being replaced, the replace
* target added to the sprout FS, so there will be no more
* device left under the seed FS.
*/
ASSERT(fs_devices->seeding);
list_del_init(&fs_devices->seed_list);
close_fs_devices(fs_devices);
free_fs_devices(fs_devices);
}
mutex_unlock(&uuid_mutex);
}
void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
{
struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
mutex_lock(&fs_devices->device_list_mutex);
btrfs_sysfs_remove_device(tgtdev);
if (tgtdev->bdev)
fs_devices->open_devices--;
fs_devices->num_devices--;
btrfs_assign_next_active_device(tgtdev, NULL);
list_del_rcu(&tgtdev->dev_list);
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev);
btrfs_close_bdev(tgtdev);
synchronize_rcu();
btrfs_free_device(tgtdev);
}
/*
* Populate args from device at path.
*
* @fs_info: the filesystem
* @args: the args to populate
* @path: the path to the device
*
* This will read the super block of the device at @path and populate @args with
* the devid, fsid, and uuid. This is meant to be used for ioctls that need to
* lookup a device to operate on, but need to do it before we take any locks.
* This properly handles the special case of "missing" that a user may pass in,
* and does some basic sanity checks. The caller must make sure that @path is
* properly NUL terminated before calling in, and must call
* btrfs_put_dev_args_from_path() in order to free up the temporary fsid and
* uuid buffers.
*
* Return: 0 for success, -errno for failure
*/
int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
struct btrfs_dev_lookup_args *args,
const char *path)
{
struct btrfs_super_block *disk_super;
struct file *bdev_file;
int ret;
if (!path || !path[0])
return -EINVAL;
if (!strcmp(path, "missing")) {
args->missing = true;
return 0;
}
args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL);
args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL);
if (!args->uuid || !args->fsid) {
btrfs_put_dev_args_from_path(args);
return -ENOMEM;
}
ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0,
&bdev_file, &disk_super);
if (ret) {
btrfs_put_dev_args_from_path(args);
return ret;
}
args->devid = btrfs_stack_device_id(&disk_super->dev_item);
memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE);
if (btrfs_fs_incompat(fs_info, METADATA_UUID))
memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE);
else
memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
btrfs_release_disk_super(disk_super);
fput(bdev_file);
return 0;
}
/*
* Only use this jointly with btrfs_get_dev_args_from_path() because we will
* allocate our ->uuid and ->fsid pointers, everybody else uses local variables
* that don't need to be freed.
*/
void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args)
{
kfree(args->uuid);
kfree(args->fsid);
args->uuid = NULL;
args->fsid = NULL;
}
struct btrfs_device *btrfs_find_device_by_devspec(
struct btrfs_fs_info *fs_info, u64 devid,
const char *device_path)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_device *device;
int ret;
if (devid) {
args.devid = devid;
device = btrfs_find_device(fs_info->fs_devices, &args);
if (!device)
return ERR_PTR(-ENOENT);
return device;
}
ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path);
if (ret)
return ERR_PTR(ret);
device = btrfs_find_device(fs_info->fs_devices, &args);
btrfs_put_dev_args_from_path(&args);
if (!device)
return ERR_PTR(-ENOENT);
return device;
}
static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_fs_devices *old_devices;
struct btrfs_fs_devices *seed_devices;
lockdep_assert_held(&uuid_mutex);
if (!fs_devices->seeding)
return ERR_PTR(-EINVAL);
/*
* Private copy of the seed devices, anchored at
* fs_info->fs_devices->seed_list
*/
seed_devices = alloc_fs_devices(NULL);
if (IS_ERR(seed_devices))
return seed_devices;
/*
* It's necessary to retain a copy of the original seed fs_devices in
* fs_uuids so that filesystems which have been seeded can successfully
* reference the seed device from open_seed_devices. This also supports
* multiple fs seed.
*/
old_devices = clone_fs_devices(fs_devices);
if (IS_ERR(old_devices)) {
kfree(seed_devices);
return old_devices;
}
list_add(&old_devices->fs_list, &fs_uuids);
memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
seed_devices->opened = 1;
INIT_LIST_HEAD(&seed_devices->devices);
INIT_LIST_HEAD(&seed_devices->alloc_list);
mutex_init(&seed_devices->device_list_mutex);
return seed_devices;
}
/*
* Splice seed devices into the sprout fs_devices.
* Generate a new fsid for the sprouted read-write filesystem.
*/
static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info,
struct btrfs_fs_devices *seed_devices)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_super_block *disk_super = fs_info->super_copy;
struct btrfs_device *device;
u64 super_flags;
/*
* We are updating the fsid, the thread leading to device_list_add()
* could race, so uuid_mutex is needed.
*/
lockdep_assert_held(&uuid_mutex);
/*
* The threads listed below may traverse dev_list but can do that without
* device_list_mutex:
* - All device ops and balance - as we are in btrfs_exclop_start.
* - Various dev_list readers - are using RCU.
* - btrfs_ioctl_fitrim() - is using RCU.
*
* For-read threads as below are using device_list_mutex:
* - Readonly scrub btrfs_scrub_dev()
* - Readonly scrub btrfs_scrub_progress()
* - btrfs_get_dev_stats()
*/
lockdep_assert_held(&fs_devices->device_list_mutex);
list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
synchronize_rcu);
list_for_each_entry(device, &seed_devices->devices, dev_list)
device->fs_devices = seed_devices;
fs_devices->seeding = false;
fs_devices->num_devices = 0;
fs_devices->open_devices = 0;
fs_devices->missing_devices = 0;
fs_devices->rotating = false;
list_add(&seed_devices->seed_list, &fs_devices->seed_list);
generate_random_uuid(fs_devices->fsid);
memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
super_flags = btrfs_super_flags(disk_super) &
~BTRFS_SUPER_FLAG_SEEDING;
btrfs_set_super_flags(disk_super, super_flags);
}
/*
* Store the expected generation for seed devices in device items.
*/
static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_dev_item *dev_item;
struct btrfs_device *device;
struct btrfs_key key;
u8 fs_uuid[BTRFS_FSID_SIZE];
u8 dev_uuid[BTRFS_UUID_SIZE];
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.offset = 0;
key.type = BTRFS_DEV_ITEM_KEY;
while (1) {
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
btrfs_trans_release_chunk_metadata(trans);
if (ret < 0)
goto error;
leaf = path->nodes[0];
next_slot:
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret > 0)
break;
if (ret < 0)
goto error;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
btrfs_release_path(path);
continue;
}
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
key.type != BTRFS_DEV_ITEM_KEY)
break;
dev_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_item);
args.devid = btrfs_device_id(leaf, dev_item);
read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
BTRFS_FSID_SIZE);
args.uuid = dev_uuid;
args.fsid = fs_uuid;
device = btrfs_find_device(fs_info->fs_devices, &args);
BUG_ON(!device); /* Logic error */
if (device->fs_devices->seeding) {
btrfs_set_device_generation(leaf, dev_item,
device->generation);
btrfs_mark_buffer_dirty(trans, leaf);
}
path->slots[0]++;
goto next_slot;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path)
{
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_trans_handle *trans;
struct btrfs_device *device;
struct file *bdev_file;
struct super_block *sb = fs_info->sb;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_fs_devices *seed_devices = NULL;
u64 orig_super_total_bytes;
u64 orig_super_num_devices;
int ret = 0;
bool seeding_dev = false;
bool locked = false;
if (sb_rdonly(sb) && !fs_devices->seeding)
return -EROFS;
bdev_file = bdev_file_open_by_path(device_path, BLK_OPEN_WRITE,
fs_info->bdev_holder, NULL);
if (IS_ERR(bdev_file))
return PTR_ERR(bdev_file);
if (!btrfs_check_device_zone_type(fs_info, file_bdev(bdev_file))) {
ret = -EINVAL;
goto error;
}
if (fs_devices->seeding) {
seeding_dev = true;
down_write(&sb->s_umount);
mutex_lock(&uuid_mutex);
locked = true;
}
sync_blockdev(file_bdev(bdev_file));
rcu_read_lock();
list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
if (device->bdev == file_bdev(bdev_file)) {
ret = -EEXIST;
rcu_read_unlock();
goto error;
}
}
rcu_read_unlock();
device = btrfs_alloc_device(fs_info, NULL, NULL, device_path);
if (IS_ERR(device)) {
/* we can safely leave the fs_devices entry around */
ret = PTR_ERR(device);
goto error;
}
device->fs_info = fs_info;
device->bdev_file = bdev_file;
device->bdev = file_bdev(bdev_file);
ret = lookup_bdev(device_path, &device->devt);
if (ret)
goto error_free_device;
ret = btrfs_get_dev_zone_info(device, false);
if (ret)
goto error_free_device;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto error_free_zone;
}
set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
device->generation = trans->transid;
device->io_width = fs_info->sectorsize;
device->io_align = fs_info->sectorsize;
device->sector_size = fs_info->sectorsize;
device->total_bytes =
round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize);
device->disk_total_bytes = device->total_bytes;
device->commit_total_bytes = device->total_bytes;
set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
device->dev_stats_valid = 1;
set_blocksize(device->bdev_file, BTRFS_BDEV_BLOCKSIZE);
if (seeding_dev) {
btrfs_clear_sb_rdonly(sb);
/* GFP_KERNEL allocation must not be under device_list_mutex */
seed_devices = btrfs_init_sprout(fs_info);
if (IS_ERR(seed_devices)) {
ret = PTR_ERR(seed_devices);
btrfs_abort_transaction(trans, ret);
goto error_trans;
}
}
mutex_lock(&fs_devices->device_list_mutex);
if (seeding_dev) {
btrfs_setup_sprout(fs_info, seed_devices);
btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev,
device);
}
device->fs_devices = fs_devices;
mutex_lock(&fs_info->chunk_mutex);
list_add_rcu(&device->dev_list, &fs_devices->devices);
list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
fs_devices->num_devices++;
fs_devices->open_devices++;
fs_devices->rw_devices++;
fs_devices->total_devices++;
fs_devices->total_rw_bytes += device->total_bytes;
atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
if (!bdev_nonrot(device->bdev))
fs_devices->rotating = true;
orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
btrfs_set_super_total_bytes(fs_info->super_copy,
round_down(orig_super_total_bytes + device->total_bytes,
fs_info->sectorsize));
orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy);
btrfs_set_super_num_devices(fs_info->super_copy,
orig_super_num_devices + 1);
/*
* we've got more storage, clear any full flags on the space
* infos
*/
btrfs_clear_space_info_full(fs_info);
mutex_unlock(&fs_info->chunk_mutex);
/* Add sysfs device entry */
btrfs_sysfs_add_device(device);
mutex_unlock(&fs_devices->device_list_mutex);
if (seeding_dev) {
mutex_lock(&fs_info->chunk_mutex);
ret = init_first_rw_device(trans);
mutex_unlock(&fs_info->chunk_mutex);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
}
ret = btrfs_add_dev_item(trans, device);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
if (seeding_dev) {
ret = btrfs_finish_sprout(trans);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
/*
* fs_devices now represents the newly sprouted filesystem and
* its fsid has been changed by btrfs_sprout_splice().
*/
btrfs_sysfs_update_sprout_fsid(fs_devices);
}
ret = btrfs_commit_transaction(trans);
if (seeding_dev) {
mutex_unlock(&uuid_mutex);
up_write(&sb->s_umount);
locked = false;
if (ret) /* transaction commit */
return ret;
ret = btrfs_relocate_sys_chunks(fs_info);
if (ret < 0)
btrfs_handle_fs_error(fs_info, ret,
"Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command.");
trans = btrfs_attach_transaction(root);
if (IS_ERR(trans)) {
if (PTR_ERR(trans) == -ENOENT)
return 0;
ret = PTR_ERR(trans);
trans = NULL;
goto error_sysfs;
}
ret = btrfs_commit_transaction(trans);
}
/*
* Now that we have written a new super block to this device, check all
* other fs_devices list if device_path alienates any other scanned
* device.
* We can ignore the return value as it typically returns -EINVAL and
* only succeeds if the device was an alien.
*/
btrfs_forget_devices(device->devt);
/* Update ctime/mtime for blkid or udev */
update_dev_time(device_path);
return ret;
error_sysfs:
btrfs_sysfs_remove_device(device);
mutex_lock(&fs_info->fs_devices->device_list_mutex);
mutex_lock(&fs_info->chunk_mutex);
list_del_rcu(&device->dev_list);
list_del(&device->dev_alloc_list);
fs_info->fs_devices->num_devices--;
fs_info->fs_devices->open_devices--;
fs_info->fs_devices->rw_devices--;
fs_info->fs_devices->total_devices--;
fs_info->fs_devices->total_rw_bytes -= device->total_bytes;
atomic64_sub(device->total_bytes, &fs_info->free_chunk_space);
btrfs_set_super_total_bytes(fs_info->super_copy,
orig_super_total_bytes);
btrfs_set_super_num_devices(fs_info->super_copy,
orig_super_num_devices);
mutex_unlock(&fs_info->chunk_mutex);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
error_trans:
if (seeding_dev)
btrfs_set_sb_rdonly(sb);
if (trans)
btrfs_end_transaction(trans);
error_free_zone:
btrfs_destroy_dev_zone_info(device);
error_free_device:
btrfs_free_device(device);
error:
fput(bdev_file);
if (locked) {
mutex_unlock(&uuid_mutex);
up_write(&sb->s_umount);
}
return ret;
}
static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
int ret;
struct btrfs_path *path;
struct btrfs_root *root = device->fs_info->chunk_root;
struct btrfs_dev_item *dev_item;
struct extent_buffer *leaf;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
if (ret < 0)
goto out;
if (ret > 0) {
ret = -ENOENT;
goto out;
}
leaf = path->nodes[0];
dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
btrfs_set_device_id(leaf, dev_item, device->devid);
btrfs_set_device_type(leaf, dev_item, device->type);
btrfs_set_device_io_align(leaf, dev_item, device->io_align);
btrfs_set_device_io_width(leaf, dev_item, device->io_width);
btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
btrfs_set_device_total_bytes(leaf, dev_item,
btrfs_device_get_disk_total_bytes(device));
btrfs_set_device_bytes_used(leaf, dev_item,
btrfs_device_get_bytes_used(device));
btrfs_mark_buffer_dirty(trans, leaf);
out:
btrfs_free_path(path);
return ret;
}
int btrfs_grow_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 new_size)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_super_block *super_copy = fs_info->super_copy;
u64 old_total;
u64 diff;
int ret;
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
return -EACCES;
new_size = round_down(new_size, fs_info->sectorsize);
mutex_lock(&fs_info->chunk_mutex);
old_total = btrfs_super_total_bytes(super_copy);
diff = round_down(new_size - device->total_bytes, fs_info->sectorsize);
if (new_size <= device->total_bytes ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
mutex_unlock(&fs_info->chunk_mutex);
return -EINVAL;
}
btrfs_set_super_total_bytes(super_copy,
round_down(old_total + diff, fs_info->sectorsize));
device->fs_devices->total_rw_bytes += diff;
atomic64_add(diff, &fs_info->free_chunk_space);
btrfs_device_set_total_bytes(device, new_size);
btrfs_device_set_disk_total_bytes(device, new_size);
btrfs_clear_space_info_full(device->fs_info);
if (list_empty(&device->post_commit_list))
list_add_tail(&device->post_commit_list,
&trans->transaction->dev_update_list);
mutex_unlock(&fs_info->chunk_mutex);
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_update_device(trans, device);
btrfs_trans_release_chunk_metadata(trans);
return ret;
}
static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->chunk_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = chunk_offset;
key.type = BTRFS_CHUNK_ITEM_KEY;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0)
goto out;
else if (ret > 0) { /* Logic error or corruption */
btrfs_err(fs_info, "failed to lookup chunk %llu when freeing",
chunk_offset);
btrfs_abort_transaction(trans, -ENOENT);
ret = -EUCLEAN;
goto out;
}
ret = btrfs_del_item(trans, root, path);
if (ret < 0) {
btrfs_err(fs_info, "failed to delete chunk %llu item", chunk_offset);
btrfs_abort_transaction(trans, ret);
goto out;
}
out:
btrfs_free_path(path);
return ret;
}
static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
{
struct btrfs_super_block *super_copy = fs_info->super_copy;
struct btrfs_disk_key *disk_key;
struct btrfs_chunk *chunk;
u8 *ptr;
int ret = 0;
u32 num_stripes;
u32 array_size;
u32 len = 0;
u32 cur;
struct btrfs_key key;
lockdep_assert_held(&fs_info->chunk_mutex);
array_size = btrfs_super_sys_array_size(super_copy);
ptr = super_copy->sys_chunk_array;
cur = 0;
while (cur < array_size) {
disk_key = (struct btrfs_disk_key *)ptr;
btrfs_disk_key_to_cpu(&key, disk_key);
len = sizeof(*disk_key);
if (key.type == BTRFS_CHUNK_ITEM_KEY) {
chunk = (struct btrfs_chunk *)(ptr + len);
num_stripes = btrfs_stack_chunk_num_stripes(chunk);
len += btrfs_chunk_item_size(num_stripes);
} else {
ret = -EIO;
break;
}
if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID &&
key.offset == chunk_offset) {
memmove(ptr, ptr + len, array_size - (cur + len));
array_size -= len;
btrfs_set_super_sys_array_size(super_copy, array_size);
} else {
ptr += len;
cur += len;
}
}
return ret;
}
struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct rb_node *node = fs_info->mapping_tree.rb_root.rb_node;
struct rb_node *prev = NULL;
struct rb_node *orig_prev;
struct btrfs_chunk_map *map;
struct btrfs_chunk_map *prev_map = NULL;
while (node) {
map = rb_entry(node, struct btrfs_chunk_map, rb_node);
prev = node;
prev_map = map;
if (logical < map->start) {
node = node->rb_left;
} else if (logical >= map->start + map->chunk_len) {
node = node->rb_right;
} else {
refcount_inc(&map->refs);
return map;
}
}
if (!prev)
return NULL;
orig_prev = prev;
while (prev && logical >= prev_map->start + prev_map->chunk_len) {
prev = rb_next(prev);
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
}
if (!prev) {
prev = orig_prev;
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
while (prev && logical < prev_map->start) {
prev = rb_prev(prev);
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
}
}
if (prev) {
u64 end = logical + length;
/*
* Caller can pass a U64_MAX length when it wants to get any
* chunk starting at an offset of 'logical' or higher, so deal
* with underflow by resetting the end offset to U64_MAX.
*/
if (end < logical)
end = U64_MAX;
if (end > prev_map->start &&
logical < prev_map->start + prev_map->chunk_len) {
refcount_inc(&prev_map->refs);
return prev_map;
}
}
return NULL;
}
struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct btrfs_chunk_map *map;
read_lock(&fs_info->mapping_tree_lock);
map = btrfs_find_chunk_map_nolock(fs_info, logical, length);
read_unlock(&fs_info->mapping_tree_lock);
return map;
}
/*
* Find the mapping containing the given logical extent.
*
* @logical: Logical block offset in bytes.
* @length: Length of extent in bytes.
*
* Return: Chunk mapping or ERR_PTR.
*/
struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct btrfs_chunk_map *map;
map = btrfs_find_chunk_map(fs_info, logical, length);
if (unlikely(!map)) {
btrfs_crit(fs_info,
"unable to find chunk map for logical %llu length %llu",
logical, length);
return ERR_PTR(-EINVAL);
}
if (unlikely(map->start > logical || map->start + map->chunk_len <= logical)) {
btrfs_crit(fs_info,
"found a bad chunk map, wanted %llu-%llu, found %llu-%llu",
logical, logical + length, map->start,
map->start + map->chunk_len);
btrfs_free_chunk_map(map);
return ERR_PTR(-EINVAL);
}
/* Callers are responsible for dropping the reference. */
return map;
}
static int remove_chunk_item(struct btrfs_trans_handle *trans,
struct btrfs_chunk_map *map, u64 chunk_offset)
{
int i;
/*
* Removing chunk items and updating the device items in the chunks btree
* requires holding the chunk_mutex.
* See the comment at btrfs_chunk_alloc() for the details.
*/
lockdep_assert_held(&trans->fs_info->chunk_mutex);
for (i = 0; i < map->num_stripes; i++) {
int ret;
ret = btrfs_update_device(trans, map->stripes[i].dev);
if (ret)
return ret;
}
return btrfs_free_chunk(trans, chunk_offset);
}
int