diff options
Diffstat (limited to 'fs/btrfs/sysfs.c')
| -rw-r--r-- | fs/btrfs/sysfs.c | 1797 |
1 files changed, 1797 insertions, 0 deletions
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c new file mode 100644 index 000000000..ecf190286 --- /dev/null +++ b/fs/btrfs/sysfs.c @@ -0,0 +1,1797 @@ +// 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/spinlock.h> +#include <linux/completion.h> +#include <linux/bug.h> +#include <crypto/hash.h> + +#include "ctree.h" +#include "discard.h" +#include "disk-io.h" +#include "send.h" +#include "transaction.h" +#include "sysfs.h" +#include "volumes.h" +#include "space-info.h" +#include "block-group.h" +#include "qgroup.h" + +struct btrfs_feature_attr { + struct kobj_attribute kobj_attr; + enum btrfs_feature_set feature_set; + u64 feature_bit; +}; + +/* For raid type sysfs entries */ +struct raid_kobject { + u64 flags; + struct kobject kobj; +}; + +#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \ +{ \ + .attr = { .name = __stringify(_name), .mode = _mode }, \ + .show = _show, \ + .store = _store, \ +} + +#define BTRFS_ATTR_RW(_prefix, _name, _show, _store) \ + static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ + __INIT_KOBJ_ATTR(_name, 0644, _show, _store) + +#define BTRFS_ATTR(_prefix, _name, _show) \ + static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ + __INIT_KOBJ_ATTR(_name, 0444, _show, NULL) + +#define BTRFS_ATTR_PTR(_prefix, _name) \ + (&btrfs_attr_##_prefix##_##_name.attr) + +#define BTRFS_FEAT_ATTR(_name, _feature_set, _feature_prefix, _feature_bit) \ +static struct btrfs_feature_attr btrfs_attr_features_##_name = { \ + .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \ + btrfs_feature_attr_show, \ + btrfs_feature_attr_store), \ + .feature_set = _feature_set, \ + .feature_bit = _feature_prefix ##_## _feature_bit, \ +} +#define BTRFS_FEAT_ATTR_PTR(_name) \ + (&btrfs_attr_features_##_name.kobj_attr.attr) + +#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature) +#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature) +#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature) + +static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj); +static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj); + +static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a) +{ + return container_of(a, struct btrfs_feature_attr, kobj_attr); +} + +static struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr) +{ + return container_of(attr, struct kobj_attribute, attr); +} + +static struct btrfs_feature_attr *attr_to_btrfs_feature_attr( + struct attribute *attr) +{ + return to_btrfs_feature_attr(attr_to_btrfs_attr(attr)); +} + +static u64 get_features(struct btrfs_fs_info *fs_info, + enum btrfs_feature_set set) +{ + struct btrfs_super_block *disk_super = fs_info->super_copy; + if (set == FEAT_COMPAT) + return btrfs_super_compat_flags(disk_super); + else if (set == FEAT_COMPAT_RO) + return btrfs_super_compat_ro_flags(disk_super); + else + return btrfs_super_incompat_flags(disk_super); +} + +static void set_features(struct btrfs_fs_info *fs_info, + enum btrfs_feature_set set, u64 features) +{ + struct btrfs_super_block *disk_super = fs_info->super_copy; + if (set == FEAT_COMPAT) + btrfs_set_super_compat_flags(disk_super, features); + else if (set == FEAT_COMPAT_RO) + btrfs_set_super_compat_ro_flags(disk_super, features); + else + btrfs_set_super_incompat_flags(disk_super, features); +} + +static int can_modify_feature(struct btrfs_feature_attr *fa) +{ + int val = 0; + u64 set, clear; + switch (fa->feature_set) { + case FEAT_COMPAT: + set = BTRFS_FEATURE_COMPAT_SAFE_SET; + clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; + break; + case FEAT_COMPAT_RO: + set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; + clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; + break; + case FEAT_INCOMPAT: + set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; + clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; + break; + default: + pr_warn("btrfs: sysfs: unknown feature set %d\n", + fa->feature_set); + return 0; + } + + if (set & fa->feature_bit) + val |= 1; + if (clear & fa->feature_bit) + val |= 2; + + return val; +} + +static ssize_t btrfs_feature_attr_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + int val = 0; + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); + if (fs_info) { + u64 features = get_features(fs_info, fa->feature_set); + if (features & fa->feature_bit) + val = 1; + } else + val = can_modify_feature(fa); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} + +static ssize_t btrfs_feature_attr_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t count) +{ + struct btrfs_fs_info *fs_info; + struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a); + u64 features, set, clear; + unsigned long val; + int ret; + + fs_info = to_fs_info(kobj); + if (!fs_info) + return -EPERM; + + if (sb_rdonly(fs_info->sb)) + return -EROFS; + + ret = kstrtoul(skip_spaces(buf), 0, &val); + if (ret) + return ret; + + if (fa->feature_set == FEAT_COMPAT) { + set = BTRFS_FEATURE_COMPAT_SAFE_SET; + clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR; + } else if (fa->feature_set == FEAT_COMPAT_RO) { + set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET; + clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR; + } else { + set = BTRFS_FEATURE_INCOMPAT_SAFE_SET; + clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR; + } + + features = get_features(fs_info, fa->feature_set); + + /* Nothing to do */ + if ((val && (features & fa->feature_bit)) || + (!val && !(features & fa->feature_bit))) + return count; + + if ((val && !(set & fa->feature_bit)) || + (!val && !(clear & fa->feature_bit))) { + btrfs_info(fs_info, + "%sabling feature %s on mounted fs is not supported.", + val ? "En" : "Dis", fa->kobj_attr.attr.name); + return -EPERM; + } + + btrfs_info(fs_info, "%s %s feature flag", + val ? "Setting" : "Clearing", fa->kobj_attr.attr.name); + + spin_lock(&fs_info->super_lock); + features = get_features(fs_info, fa->feature_set); + if (val) + features |= fa->feature_bit; + else + features &= ~fa->feature_bit; + set_features(fs_info, fa->feature_set, features); + spin_unlock(&fs_info->super_lock); + + /* + * We don't want to do full transaction commit from inside sysfs + */ + btrfs_set_pending(fs_info, COMMIT); + wake_up_process(fs_info->transaction_kthread); + + return count; +} + +static umode_t btrfs_feature_visible(struct kobject *kobj, + struct attribute *attr, int unused) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + umode_t mode = attr->mode; + + if (fs_info) { + struct btrfs_feature_attr *fa; + u64 features; + + fa = attr_to_btrfs_feature_attr(attr); + features = get_features(fs_info, fa->feature_set); + + if (can_modify_feature(fa)) + mode |= S_IWUSR; + else if (!(features & fa->feature_bit)) + mode = 0; + } + + return mode; +} + +BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF); +BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL); +BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS); +BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO); +BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD); +BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA); +BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF); +BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56); +BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA); +BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES); +BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID); +BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE); +BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34); + +static struct attribute *btrfs_supported_feature_attrs[] = { + BTRFS_FEAT_ATTR_PTR(mixed_backref), + BTRFS_FEAT_ATTR_PTR(default_subvol), + BTRFS_FEAT_ATTR_PTR(mixed_groups), + BTRFS_FEAT_ATTR_PTR(compress_lzo), + BTRFS_FEAT_ATTR_PTR(compress_zstd), + BTRFS_FEAT_ATTR_PTR(big_metadata), + BTRFS_FEAT_ATTR_PTR(extended_iref), + BTRFS_FEAT_ATTR_PTR(raid56), + BTRFS_FEAT_ATTR_PTR(skinny_metadata), + BTRFS_FEAT_ATTR_PTR(no_holes), + BTRFS_FEAT_ATTR_PTR(metadata_uuid), + BTRFS_FEAT_ATTR_PTR(free_space_tree), + BTRFS_FEAT_ATTR_PTR(raid1c34), + NULL +}; + +/* + * Features which depend on feature bits and may differ between each fs. + * + * /sys/fs/btrfs/features lists all available features of this kernel while + * /sys/fs/btrfs/UUID/features shows features of the fs which are enabled or + * can be changed online. + */ +static const struct attribute_group btrfs_feature_attr_group = { + .name = "features", + .is_visible = btrfs_feature_visible, + .attrs = btrfs_supported_feature_attrs, +}; + +static ssize_t rmdir_subvol_show(struct kobject *kobj, + struct kobj_attribute *ka, char *buf) +{ + return scnprintf(buf, PAGE_SIZE, "0\n"); +} +BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show); + +static ssize_t supported_checksums_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + ssize_t ret = 0; + int i; + + for (i = 0; i < btrfs_get_num_csums(); i++) { + /* + * This "trick" only works as long as 'enum btrfs_csum_type' has + * no holes in it + */ + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s", + (i == 0 ? "" : " "), btrfs_super_csum_name(i)); + + } + + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n"); + return ret; +} +BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show); + +static ssize_t send_stream_version_show(struct kobject *kobj, + struct kobj_attribute *ka, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", BTRFS_SEND_STREAM_VERSION); +} +BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show); + +static struct attribute *btrfs_supported_static_feature_attrs[] = { + BTRFS_ATTR_PTR(static_feature, rmdir_subvol), + BTRFS_ATTR_PTR(static_feature, supported_checksums), + BTRFS_ATTR_PTR(static_feature, send_stream_version), + NULL +}; + +/* + * Features which only depend on kernel version. + * + * These are listed in /sys/fs/btrfs/features along with + * btrfs_feature_attr_group + */ +static const struct attribute_group btrfs_static_feature_attr_group = { + .name = "features", + .attrs = btrfs_supported_static_feature_attrs, +}; + +#ifdef CONFIG_BTRFS_DEBUG + +/* + * Discard statistics and tunables + */ +#define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent) + +static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%lld\n", + atomic64_read(&fs_info->discard_ctl.discardable_bytes)); +} +BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show); + +static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%d\n", + atomic_read(&fs_info->discard_ctl.discardable_extents)); +} +BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show); + +static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%llu\n", + fs_info->discard_ctl.discard_bitmap_bytes); +} +BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show); + +static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%lld\n", + atomic64_read(&fs_info->discard_ctl.discard_bytes_saved)); +} +BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show); + +static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%llu\n", + fs_info->discard_ctl.discard_extent_bytes); +} +BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show); + +static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%u\n", + READ_ONCE(fs_info->discard_ctl.iops_limit)); +} + +static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t len) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; + u32 iops_limit; + int ret; + + ret = kstrtou32(buf, 10, &iops_limit); + if (ret) + return -EINVAL; + + WRITE_ONCE(discard_ctl->iops_limit, iops_limit); + + return len; +} +BTRFS_ATTR_RW(discard, iops_limit, btrfs_discard_iops_limit_show, + btrfs_discard_iops_limit_store); + +static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%u\n", + READ_ONCE(fs_info->discard_ctl.kbps_limit)); +} + +static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t len) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; + u32 kbps_limit; + int ret; + + ret = kstrtou32(buf, 10, &kbps_limit); + if (ret) + return -EINVAL; + + WRITE_ONCE(discard_ctl->kbps_limit, kbps_limit); + + return len; +} +BTRFS_ATTR_RW(discard, kbps_limit, btrfs_discard_kbps_limit_show, + btrfs_discard_kbps_limit_store); + +static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%llu\n", + READ_ONCE(fs_info->discard_ctl.max_discard_size)); +} + +static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t len) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + struct btrfs_discard_ctl *discard_ctl = &fs_info->discard_ctl; + u64 max_discard_size; + int ret; + + ret = kstrtou64(buf, 10, &max_discard_size); + if (ret) + return -EINVAL; + + WRITE_ONCE(discard_ctl->max_discard_size, max_discard_size); + + return len; +} +BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show, + btrfs_discard_max_discard_size_store); + +static const struct attribute *discard_debug_attrs[] = { + BTRFS_ATTR_PTR(discard, discardable_bytes), + BTRFS_ATTR_PTR(discard, discardable_extents), + BTRFS_ATTR_PTR(discard, discard_bitmap_bytes), + BTRFS_ATTR_PTR(discard, discard_bytes_saved), + BTRFS_ATTR_PTR(discard, discard_extent_bytes), + BTRFS_ATTR_PTR(discard, iops_limit), + BTRFS_ATTR_PTR(discard, kbps_limit), + BTRFS_ATTR_PTR(discard, max_discard_size), + NULL, +}; + +/* + * Runtime debugging exported via sysfs + * + * /sys/fs/btrfs/debug - applies to module or all filesystems + * /sys/fs/btrfs/UUID - applies only to the given filesystem + */ +static const struct attribute *btrfs_debug_mount_attrs[] = { + NULL, +}; + +static struct attribute *btrfs_debug_feature_attrs[] = { + NULL +}; + +static const struct attribute_group btrfs_debug_feature_attr_group = { + .name = "debug", + .attrs = btrfs_debug_feature_attrs, +}; + +#endif + +static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf) +{ + u64 val; + if (lock) + spin_lock(lock); + val = *value_ptr; + if (lock) + spin_unlock(lock); + return scnprintf(buf, PAGE_SIZE, "%llu\n", val); +} + +static ssize_t global_rsv_size_show(struct kobject *kobj, + struct kobj_attribute *ka, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); + struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; + return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf); +} +BTRFS_ATTR(allocation, global_rsv_size, global_rsv_size_show); + +static ssize_t global_rsv_reserved_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent); + struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; + return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf); +} +BTRFS_ATTR(allocation, global_rsv_reserved, global_rsv_reserved_show); + +#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj) +#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj) + +static ssize_t raid_bytes_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf); +BTRFS_ATTR(raid, total_bytes, raid_bytes_show); +BTRFS_ATTR(raid, used_bytes, raid_bytes_show); + +static ssize_t raid_bytes_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) + +{ + struct btrfs_space_info *sinfo = to_space_info(kobj->parent); + struct btrfs_block_group *block_group; + int index = btrfs_bg_flags_to_raid_index(to_raid_kobj(kobj)->flags); + u64 val = 0; + + down_read(&sinfo->groups_sem); + list_for_each_entry(block_group, &sinfo->block_groups[index], list) { + if (&attr->attr == BTRFS_ATTR_PTR(raid, total_bytes)) + val += block_group->length; + else + val += block_group->used; + } + up_read(&sinfo->groups_sem); + return scnprintf(buf, PAGE_SIZE, "%llu\n", val); +} + +static struct attribute *raid_attrs[] = { + BTRFS_ATTR_PTR(raid, total_bytes), + BTRFS_ATTR_PTR(raid, used_bytes), + NULL +}; +ATTRIBUTE_GROUPS(raid); + +static void release_raid_kobj(struct kobject *kobj) +{ + kfree(to_raid_kobj(kobj)); +} + +static struct kobj_type btrfs_raid_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .release = release_raid_kobj, + .default_groups = raid_groups, +}; + +#define SPACE_INFO_ATTR(field) \ +static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \ + struct kobj_attribute *a, \ + char *buf) \ +{ \ + struct btrfs_space_info *sinfo = to_space_info(kobj); \ + return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \ +} \ +BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field) + +static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_space_info *sinfo = to_space_info(kobj); + s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned); + return scnprintf(buf, PAGE_SIZE, "%lld\n", val); +} + +SPACE_INFO_ATTR(flags); +SPACE_INFO_ATTR(total_bytes); +SPACE_INFO_ATTR(bytes_used); +SPACE_INFO_ATTR(bytes_pinned); +SPACE_INFO_ATTR(bytes_reserved); +SPACE_INFO_ATTR(bytes_may_use); +SPACE_INFO_ATTR(bytes_readonly); +SPACE_INFO_ATTR(disk_used); +SPACE_INFO_ATTR(disk_total); +BTRFS_ATTR(space_info, total_bytes_pinned, + btrfs_space_info_show_total_bytes_pinned); + +static struct attribute *space_info_attrs[] = { + BTRFS_ATTR_PTR(space_info, flags), + BTRFS_ATTR_PTR(space_info, total_bytes), + BTRFS_ATTR_PTR(space_info, bytes_used), + BTRFS_ATTR_PTR(space_info, bytes_pinned), + BTRFS_ATTR_PTR(space_info, bytes_reserved), + BTRFS_ATTR_PTR(space_info, bytes_may_use), + BTRFS_ATTR_PTR(space_info, bytes_readonly), + BTRFS_ATTR_PTR(space_info, disk_used), + BTRFS_ATTR_PTR(space_info, disk_total), + BTRFS_ATTR_PTR(space_info, total_bytes_pinned), + NULL, +}; +ATTRIBUTE_GROUPS(space_info); + +static void space_info_release(struct kobject *kobj) +{ + struct btrfs_space_info *sinfo = to_space_info(kobj); + percpu_counter_destroy(&sinfo->total_bytes_pinned); + kfree(sinfo); +} + +static struct kobj_type space_info_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .release = space_info_release, + .default_groups = space_info_groups, +}; + +static const struct attribute *allocation_attrs[] = { + BTRFS_ATTR_PTR(allocation, global_rsv_reserved), + BTRFS_ATTR_PTR(allocation, global_rsv_size), + NULL, +}; + +static ssize_t btrfs_label_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + char *label = fs_info->super_copy->label; + ssize_t ret; + + spin_lock(&fs_info->super_lock); + ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label); + spin_unlock(&fs_info->super_lock); + + return ret; +} + +static ssize_t btrfs_label_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t len) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + size_t p_len; + + if (!fs_info) + return -EPERM; + + if (sb_rdonly(fs_info->sb)) + return -EROFS; + + /* + * p_len is the len until the first occurrence of either + * '\n' or '\0' + */ + p_len = strcspn(buf, "\n"); + + if (p_len >= BTRFS_LABEL_SIZE) + return -EINVAL; + + spin_lock(&fs_info->super_lock); + memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE); + memcpy(fs_info->super_copy->label, buf, p_len); + spin_unlock(&fs_info->super_lock); + + /* + * We don't want to do full transaction commit from inside sysfs + */ + btrfs_set_pending(fs_info, COMMIT); + wake_up_process(fs_info->transaction_kthread); + + return len; +} +BTRFS_ATTR_RW(, label, btrfs_label_show, btrfs_label_store); + +static ssize_t btrfs_nodesize_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize); +} + +BTRFS_ATTR(, nodesize, btrfs_nodesize_show); + +static ssize_t btrfs_sectorsize_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%u\n", + fs_info->super_copy->sectorsize); +} + +BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show); + +static ssize_t btrfs_clone_alignment_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize); +} + +BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show); + +static ssize_t quota_override_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + int quota_override; + + quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); + return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override); +} + +static ssize_t quota_override_store(struct kobject *kobj, + struct kobj_attribute *a, + const char *buf, size_t len) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + unsigned long knob; + int err; + + if (!fs_info) + return -EPERM; + + if (!capable(CAP_SYS_RESOURCE)) + return -EPERM; + + err = kstrtoul(buf, 10, &knob); + if (err) + return err; + if (knob > 1) + return -EINVAL; + + if (knob) + set_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); + else + clear_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags); + + return len; +} + +BTRFS_ATTR_RW(, quota_override, quota_override_show, quota_override_store); + +static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + + return scnprintf(buf, PAGE_SIZE, "%pU\n", + fs_info->fs_devices->metadata_uuid); +} + +BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show); + +static ssize_t btrfs_checksum_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + u16 csum_type = btrfs_super_csum_type(fs_info->super_copy); + + return scnprintf(buf, PAGE_SIZE, "%s (%s)\n", + btrfs_super_csum_name(csum_type), + crypto_shash_driver_name(fs_info->csum_shash)); +} + +BTRFS_ATTR(, checksum, btrfs_checksum_show); + +static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + struct btrfs_fs_info *fs_info = to_fs_info(kobj); + const char *str; + + switch (READ_ONCE(fs_info->exclusive_operation)) { + case BTRFS_EXCLOP_NONE: + str = "none\n"; + break; + case BTRFS_EXCLOP_BALANCE: + str = "balance\n"; + break; + case BTRFS_EXCLOP_DEV_ADD: + str = "device add\n"; + break; + case BTRFS_EXCLOP_DEV_REMOVE: + str = "device remove\n"; + break; + case BTRFS_EXCLOP_DEV_REPLACE: + str = "device replace\n"; + break; + case BTRFS_EXCLOP_RESIZE: + str = "resize\n"; + break; + case BTRFS_EXCLOP_SWAP_ACTIVATE: + str = "swap activate\n"; + break; + default: + str = "UNKNOWN\n"; + break; + } + return scnprintf(buf, PAGE_SIZE, "%s", str); +} +BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show); + +static const struct attribute *btrfs_attrs[] = { + BTRFS_ATTR_PTR(, label), + BTRFS_ATTR_PTR(, nodesize), + BTRFS_ATTR_PTR(, sectorsize), + BTRFS_ATTR_PTR(, clone_alignment), + BTRFS_ATTR_PTR(, quota_override), + BTRFS_ATTR_PTR(, metadata_uuid), + BTRFS_ATTR_PTR(, checksum), + BTRFS_ATTR_PTR(, exclusive_operation), + NULL, +}; + +static void btrfs_release_fsid_kobj(struct kobject *kobj) +{ + struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj); + + memset(&fs_devs->fsid_kobj, 0, sizeof(struct kobject)); + complete(&fs_devs->kobj_unregister); +} + +static struct kobj_type btrfs_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .release = btrfs_release_fsid_kobj, +}; + +static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj) +{ + if (kobj->ktype != &btrfs_ktype) + return NULL; + return container_of(kobj, struct btrfs_fs_devices, fsid_kobj); +} + +static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj) +{ + if (kobj->ktype != &btrfs_ktype) + return NULL; + return to_fs_devs(kobj)->fs_info; +} + +#define NUM_FEATURE_BITS 64 +#define BTRFS_FEATURE_NAME_MAX 13 +static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX]; +static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS]; + +static const u64 supported_feature_masks[FEAT_MAX] = { + [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP, + [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP, + [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP, +}; + +static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add) +{ + int set; + + for (set = 0; set < FEAT_MAX; set++) { + int i; + struct attribute *attrs[2]; + struct attribute_group agroup = { + .name = "features", + .attrs = attrs, + }; + u64 features = get_features(fs_info, set); + features &= ~supported_feature_masks[set]; + + if (!features) + continue; + + attrs[1] = NULL; + for (i = 0; i < NUM_FEATURE_BITS; i++) { + struct btrfs_feature_attr *fa; + + if (!(features & (1ULL << i))) + continue; + + fa = &btrfs_feature_attrs[set][i]; + attrs[0] = &fa->kobj_attr.attr; + if (add) { + int ret; + ret = sysfs_merge_group(&fs_info->fs_devices->fsid_kobj, + &agroup); + if (ret) + return ret; + } else + sysfs_unmerge_group(&fs_info->fs_devices->fsid_kobj, + &agroup); + } + + } + return 0; +} + +static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) +{ + if (fs_devs->devinfo_kobj) { + kobject_del(fs_devs->devinfo_kobj); + kobject_put(fs_devs->devinfo_kobj); + fs_devs->devinfo_kobj = NULL; + } + + if (fs_devs->devices_kobj) { + kobject_del(fs_devs->devices_kobj); + kobject_put(fs_devs->devices_kobj); + fs_devs->devices_kobj = NULL; + } + + if (fs_devs->fsid_kobj.state_initialized) { + kobject_del(&fs_devs->fsid_kobj); + kobject_put(&fs_devs->fsid_kobj); + wait_for_completion(&fs_devs->kobj_unregister); + } +} + +/* when fs_devs is NULL it will remove all fsid kobject */ +void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs) +{ + struct list_head *fs_uuids = btrfs_get_fs_uuids(); + + if (fs_devs) { + __btrfs_sysfs_remove_fsid(fs_devs); + return; + } + + list_for_each_entry(fs_devs, fs_uuids, fs_list) { + __btrfs_sysfs_remove_fsid(fs_devs); + } +} + +static void btrfs_sysfs_remove_fs_devices(struct btrfs_fs_devices *fs_devices) +{ + struct btrfs_device *device; + struct btrfs_fs_devices *seed; + + list_for_each_entry(device, &fs_devices->devices, dev_list) + btrfs_sysfs_remove_device(device); + + list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { + list_for_each_entry(device, &seed->devices, dev_list) + btrfs_sysfs_remove_device(device); + } +} + +void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info) +{ + struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; + + sysfs_remove_link(fsid_kobj, "bdi"); + + if (fs_info->space_info_kobj) { + sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); + kobject_del(fs_info->space_info_kobj); + kobject_put(fs_info->space_info_kobj); + } +#ifdef CONFIG_BTRFS_DEBUG + if (fs_info->discard_debug_kobj) { + sysfs_remove_files(fs_info->discard_debug_kobj, + discard_debug_attrs); + kobject_del(fs_info->discard_debug_kobj); + kobject_put(fs_info->discard_debug_kobj); + } + if (fs_info->debug_kobj) { + sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); + kobject_del(fs_info->debug_kobj); + kobject_put(fs_info->debug_kobj); + } +#endif + addrm_unknown_feature_attrs(fs_info, false); + sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); + sysfs_remove_files(fsid_kobj, btrfs_attrs); + btrfs_sysfs_remove_fs_devices(fs_info->fs_devices); +} + +static const char * const btrfs_feature_set_names[FEAT_MAX] = { + [FEAT_COMPAT] = "compat", + [FEAT_COMPAT_RO] = "compat_ro", + [FEAT_INCOMPAT] = "incompat", +}; + +const char *btrfs_feature_set_name(enum btrfs_feature_set set) +{ + return btrfs_feature_set_names[set]; +} + +char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags) +{ + size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */ + int len = 0; + int i; + char *str; + + str = kmalloc(bufsize, GFP_KERNEL); + if (!str) + return str; + + for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { + const char *name; + + if (!(flags & (1ULL << i))) + continue; + + name = btrfs_feature_attrs[set][i].kobj_attr.attr.name; + len += scnprintf(str + len, bufsize - len, "%s%s", + len ? "," : "", name); + } + + return str; +} + +static void init_feature_attrs(void) +{ + struct btrfs_feature_attr *fa; + int set, i; + + BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) != + ARRAY_SIZE(btrfs_feature_attrs)); + BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) != + ARRAY_SIZE(btrfs_feature_attrs[0])); + + memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs)); + memset(btrfs_unknown_feature_names, 0, + sizeof(btrfs_unknown_feature_names)); + + for (i = 0; btrfs_supported_feature_attrs[i]; i++) { + struct btrfs_feature_attr *sfa; + struct attribute *a = btrfs_supported_feature_attrs[i]; + int bit; + sfa = attr_to_btrfs_feature_attr(a); + bit = ilog2(sfa->feature_bit); + fa = &btrfs_feature_attrs[sfa->feature_set][bit]; + + fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name; + } + + for (set = 0; set < FEAT_MAX; set++) { + for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) { + char *name = btrfs_unknown_feature_names[set][i]; + fa = &btrfs_feature_attrs[set][i]; + + if (fa->kobj_attr.attr.name) + continue; + + snprintf(name, BTRFS_FEATURE_NAME_MAX, "%s:%u", + btrfs_feature_set_names[set], i); + + fa->kobj_attr.attr.name = name; + fa->kobj_attr.attr.mode = S_IRUGO; + fa->feature_set = set; + fa->feature_bit = 1ULL << i; + } + } +} + +/* + * Create a sysfs entry for a given block group type at path + * /sys/fs/btrfs/UUID/allocation/data/TYPE + */ +void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache) +{ + struct btrfs_fs_info *fs_info = cache->fs_info; + struct btrfs_space_info *space_info = cache->space_info; + struct raid_kobject *rkobj; + const int index = btrfs_bg_flags_to_raid_index(cache->flags); + unsigned int nofs_flag; + int ret; + + /* + * Setup a NOFS context because kobject_add(), deep in its call chain, + * does GFP_KERNEL allocations, and we are often called in a context + * where if reclaim is triggered we can deadlock (we are either holding + * a transaction handle or some lock required for a transaction + * commit). + */ + nofs_flag = memalloc_nofs_save(); + + rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS); + if (!rkobj) { + memalloc_nofs_restore(nofs_flag); + btrfs_warn(cache->fs_info, + "couldn't alloc memory for raid level kobject"); + return; + } + + rkobj->flags = cache->flags; + kobject_init(&rkobj->kobj, &btrfs_raid_ktype); + + /* + * We call this either on mount, or if we've created a block group for a + * new index type while running (i.e. when restriping). The running + * case is tricky because we could race with other threads, so we need + * to have this check to make sure we didn't already init the kobject. + * + * We don't have to protect on the free side because it only happens on + * unmount. + */ + spin_lock(&space_info->lock); + if (space_info->block_group_kobjs[index]) { + spin_unlock(&space_info->lock); + kobject_put(&rkobj->kobj); + return; + } else { + space_info->block_group_kobjs[index] = &rkobj->kobj; + } + spin_unlock(&space_info->lock); + + ret = kobject_add(&rkobj->kobj, &space_info->kobj, "%s", + btrfs_bg_type_to_raid_name(rkobj->flags)); + memalloc_nofs_restore(nofs_flag); + if (ret) { + spin_lock(&space_info->lock); + space_info->block_group_kobjs[index] = NULL; + spin_unlock(&space_info->lock); + kobject_put(&rkobj->kobj); + btrfs_warn(fs_info, + "failed to add kobject for block cache, ignoring"); + return; + } +} + +/* + * Remove sysfs directories for all block group types of a given space info and + * the space info as well + */ +void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info) +{ + int i; + + for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { + struct kobject *kobj; + + kobj = space_info->block_group_kobjs[i]; + space_info->block_group_kobjs[i] = NULL; + if (kobj) { + kobject_del(kobj); + kobject_put(kobj); + } + } + kobject_del(&space_info->kobj); + kobject_put(&space_info->kobj); +} + +static const char *alloc_name(u64 flags) +{ + switch (flags) { + case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA: + return "mixed"; + case BTRFS_BLOCK_GROUP_METADATA: + return "metadata"; + case BTRFS_BLOCK_GROUP_DATA: + return "data"; + case BTRFS_BLOCK_GROUP_SYSTEM: + return "system"; + default: + WARN_ON(1); + return "invalid-combination"; + }; +} + +/* + * Create a sysfs entry for a space info type at path + * /sys/fs/btrfs/UUID/allocation/TYPE + */ +int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info, + struct btrfs_space_info *space_info) +{ + int ret; + + ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype, + fs_info->space_info_kobj, "%s", + alloc_name(space_info->flags)); + if (ret) { + kobject_put(&space_info->kobj); + return ret; + } + + return 0; +} + +void btrfs_sysfs_remove_device(struct btrfs_device *device) +{ + struct hd_struct *disk; + struct kobject *disk_kobj; + struct kobject *devices_kobj; + + /* + * Seed fs_devices devices_kobj aren't used, fetch kobject from the + * fs_info::fs_devices. + */ + devices_kobj = device->fs_info->fs_devices->devices_kobj; + ASSERT(devices_kobj); + + if (device->bdev) { + disk = device->bdev->bd_part; + disk_kobj = &part_to_dev(disk)->kobj; + sysfs_remove_link(devices_kobj, disk_kobj->name); + } + + if (device->devid_kobj.state_initialized) { + kobject_del(&device->devid_kobj); + kobject_put(&device->devid_kobj); + wait_for_completion(&device->kobj_unregister); + } +} + +static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + int val; + struct btrfs_device *device = container_of(kobj, struct btrfs_device, + devid_kobj); + + val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} +BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show); + +static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + int val; + struct btrfs_device *device = container_of(kobj, struct btrfs_device, + devid_kobj); + + val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} +BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show); + +static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + int val; + struct btrfs_device *device = container_of(kobj, struct btrfs_device, + devid_kobj); + + val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} +BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show); + +static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + int val; + struct btrfs_device *device = container_of(kobj, struct btrfs_device, + devid_kobj); + + val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} +BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show); + +static struct attribute *devid_attrs[] = { + BTRFS_ATTR_PTR(devid, in_fs_metadata), + BTRFS_ATTR_PTR(devid, missing), + BTRFS_ATTR_PTR(devid, replace_target), + BTRFS_ATTR_PTR(devid, writeable), + NULL +}; +ATTRIBUTE_GROUPS(devid); + +static void btrfs_release_devid_kobj(struct kobject *kobj) +{ + struct btrfs_device *device = container_of(kobj, struct btrfs_device, + devid_kobj); + + memset(&device->devid_kobj, 0, sizeof(struct kobject)); + complete(&device->kobj_unregister); +} + +static struct kobj_type devid_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = devid_groups, + .release = btrfs_release_devid_kobj, +}; + +int btrfs_sysfs_add_device(struct btrfs_device *device) +{ + int ret; + unsigned int nofs_flag; + struct kobject *devices_kobj; + struct kobject *devinfo_kobj; + + /* + * Make sure we use the fs_info::fs_devices to fetch the kobjects even + * for the seed fs_devices + */ + devices_kobj = device->fs_info->fs_devices->devices_kobj; + devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj; + ASSERT(devices_kobj); + ASSERT(devinfo_kobj); + + nofs_flag = memalloc_nofs_save(); + + if (device->bdev) { + struct hd_struct *disk; + struct kobject *disk_kobj; + + disk = device->bdev->bd_part; + disk_kobj = &part_to_dev(disk)->kobj; + + ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name); + if (ret) { + btrfs_warn(device->fs_info, + "creating sysfs device link for devid %llu failed: %d", + device->devid, ret); + goto out; + } + } + + init_completion(&device->kobj_unregister); + ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype, + devinfo_kobj, "%llu", device->devid); + if (ret) { + kobject_put(&device->devid_kobj); + btrfs_warn(device->fs_info, + "devinfo init for devid %llu failed: %d", + device->devid, ret); + } + +out: + memalloc_nofs_restore(nofs_flag); + return ret; +} + +static int btrfs_sysfs_add_fs_devices(struct btrfs_fs_devices *fs_devices) +{ + int ret; + struct btrfs_device *device; + struct btrfs_fs_devices *seed; + + list_for_each_entry(device, &fs_devices->devices, dev_list) { + ret = btrfs_sysfs_add_device(device); + if (ret) + goto fail; + } + + list_for_each_entry(seed, &fs_devices->seed_list, seed_list) { + list_for_each_entry(device, &seed->devices, dev_list) { + ret = btrfs_sysfs_add_device(device); + if (ret) + goto fail; + } + } + + return 0; + +fail: + btrfs_sysfs_remove_fs_devices(fs_devices); + return ret; +} + +void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action) +{ + int ret; + + ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); + if (ret) + pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n", + action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), + &disk_to_dev(bdev->bd_disk)->kobj); +} + +void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices) + +{ + char fsid_buf[BTRFS_UUID_UNPARSED_SIZE]; + + /* + * Sprouting changes fsid of the mounted filesystem, rename the fsid + * directory + */ + snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU", fs_devices->fsid); + if (kobject_rename(&fs_devices->fsid_kobj, fsid_buf)) + btrfs_warn(fs_devices->fs_info, + "sysfs: failed to create fsid for sprout"); +} + +void btrfs_sysfs_update_devid(struct btrfs_device *device) +{ + char tmp[24]; + + snprintf(tmp, sizeof(tmp), "%llu", device->devid); + + if (kobject_rename(&device->devid_kobj, tmp)) + btrfs_warn(device->fs_devices->fs_info, + "sysfs: failed to update devid for %llu", + device->devid); +} + +/* /sys/fs/btrfs/ entry */ +static struct kset *btrfs_kset; + +/* + * Creates: + * /sys/fs/btrfs/UUID + * + * Can be called by the device discovery thread. + */ +int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs) +{ + int error; + + init_completion(&fs_devs->kobj_unregister); + fs_devs->fsid_kobj.kset = btrfs_kset; + error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL, + "%pU", fs_devs->fsid); + if (error) { + kobject_put(&fs_devs->fsid_kobj); + return error; + } + + fs_devs->devices_kobj = kobject_create_and_add("devices", + &fs_devs->fsid_kobj); + if (!fs_devs->devices_kobj) { + btrfs_err(fs_devs->fs_info, + "failed to init sysfs device interface"); + btrfs_sysfs_remove_fsid(fs_devs); + return -ENOMEM; + } + + fs_devs->devinfo_kobj = kobject_create_and_add("devinfo", + &fs_devs->fsid_kobj); + if (!fs_devs->devinfo_kobj) { + btrfs_err(fs_devs->fs_info, + "failed to init sysfs devinfo kobject"); + btrfs_sysfs_remove_fsid(fs_devs); + return -ENOMEM; + } + + return 0; +} + +int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info) +{ + int error; + struct btrfs_fs_devices *fs_devs = fs_info->fs_devices; + struct kobject *fsid_kobj = &fs_devs->fsid_kobj; + + error = btrfs_sysfs_add_fs_devices(fs_devs); + if (error) + return error; + + error = sysfs_create_files(fsid_kobj, btrfs_attrs); + if (error) { + btrfs_sysfs_remove_fs_devices(fs_devs); + return error; + } + + error = sysfs_create_group(fsid_kobj, + &btrfs_feature_attr_group); + if (error) + goto failure; + +#ifdef CONFIG_BTRFS_DEBUG + fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj); + if (!fs_info->debug_kobj) { + error = -ENOMEM; + goto failure; + } + + error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs); + if (error) + goto failure; + + /* Discard directory */ + fs_info->discard_debug_kobj = kobject_create_and_add("discard", + fs_info->debug_kobj); + if (!fs_info->discard_debug_kobj) { + error = -ENOMEM; + goto failure; + } + + error = sysfs_create_files(fs_info->discard_debug_kobj, + discard_debug_attrs); + if (error) + goto failure; +#endif + + error = addrm_unknown_feature_attrs(fs_info, true); + if (error) + goto failure; + + error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi"); + if (error) + goto failure; + + fs_info->space_info_kobj = kobject_create_and_add("allocation", + fsid_kobj); + if (!fs_info->space_info_kobj) { + error = -ENOMEM; + goto failure; + } + + error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs); + if (error) + goto failure; + + return 0; +failure: + btrfs_sysfs_remove_mounted(fs_info); + return error; +} + +static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj) +{ + return to_fs_info(kobj->parent->parent); +} + +#define QGROUP_ATTR(_member, _show_name) \ +static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \ + struct kobj_attribute *a, \ + char *buf) \ +{ \ + struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ + struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ + struct btrfs_qgroup, kobj); \ + return btrfs_show_u64(&qgroup->_member, &fs_info->qgroup_lock, buf); \ +} \ +BTRFS_ATTR(qgroup, _show_name, btrfs_qgroup_show_##_member) + +#define QGROUP_RSV_ATTR(_name, _type) \ +static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj, \ + struct kobj_attribute *a, \ + char *buf) \ +{ \ + struct btrfs_fs_info *fs_info = qgroup_kobj_to_fs_info(qgroup_kobj); \ + struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \ + struct btrfs_qgroup, kobj); \ + return btrfs_show_u64(&qgroup->rsv.values[_type], \ + &fs_info->qgroup_lock, buf); \ +} \ +BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name) + +QGROUP_ATTR(rfer, referenced); +QGROUP_ATTR(excl, exclusive); +QGROUP_ATTR(max_rfer, max_referenced); +QGROUP_ATTR(max_excl, max_exclusive); +QGROUP_ATTR(lim_flags, limit_flags); +QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA); +QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS); +QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC); + +static struct attribute *qgroup_attrs[] = { + BTRFS_ATTR_PTR(qgroup, referenced), + BTRFS_ATTR_PTR(qgroup, exclusive), + BTRFS_ATTR_PTR(qgroup, max_referenced), + BTRFS_ATTR_PTR(qgroup, max_exclusive), + BTRFS_ATTR_PTR(qgroup, limit_flags), + BTRFS_ATTR_PTR(qgroup, rsv_data), + BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans), + BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc), + NULL +}; +ATTRIBUTE_GROUPS(qgroup); + +static void qgroup_release(struct kobject *kobj) +{ + struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup, kobj); + + memset(&qgroup->kobj, 0, sizeof(*kobj)); +} + +static struct kobj_type qgroup_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .release = qgroup_release, + .default_groups = qgroup_groups, +}; + +int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup *qgroup) +{ + struct kobject *qgroups_kobj = fs_info->qgroups_kobj; + int ret; + + if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) + return 0; + if (qgroup->kobj.state_initialized) + return 0; + if (!qgroups_kobj) + return -EINVAL; + + ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj, + "%hu_%llu", btrfs_qgroup_level(qgroup->qgroupid), + btrfs_qgroup_subvolid(qgroup->qgroupid)); + if (ret < 0) + kobject_put(&qgroup->kobj); + + return ret; +} + +void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info) +{ + struct btrfs_qgroup *qgroup; + struct btrfs_qgroup *next; + + if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) + return; + + rbtree_postorder_for_each_entry_safe(qgroup, next, + &fs_info->qgroup_tree, node) + btrfs_sysfs_del_one_qgroup(fs_info, qgroup); + if (fs_info->qgroups_kobj) { + kobject_del(fs_info->qgroups_kobj); + kobject_put(fs_info->qgroups_kobj); + fs_info->qgroups_kobj = NULL; + } +} + +/* Called when qgroups get initialized, thus there is no need for locking */ +int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info) +{ + struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj; + struct btrfs_qgroup *qgroup; + struct btrfs_qgroup *next; + int ret = 0; + + if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) + return 0; + + ASSERT(fsid_kobj); + if (fs_info->qgroups_kobj) + return 0; + + fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj); + if (!fs_info->qgroups_kobj) { + ret = -ENOMEM; + goto out; + } + rbtree_postorder_for_each_entry_safe(qgroup, next, + &fs_info->qgroup_tree, node) { + ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); + if (ret < 0) + goto out; + } + +out: + if (ret < 0) + btrfs_sysfs_del_qgroups(fs_info); + return ret; +} + +void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup *qgroup) +{ + if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state)) + return; + + if (qgroup->kobj.state_initialized) { + kobject_del(&qgroup->kobj); + kobject_put(&qgroup->kobj); + } +} + +/* + * Change per-fs features in /sys/fs/btrfs/UUID/features to match current + * values in superblock. Call after any changes to incompat/compat_ro flags + */ +void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info, + u64 bit, enum btrfs_feature_set set) +{ + struct btrfs_fs_devices *fs_devs; + struct kobject *fsid_kobj; + u64 __maybe_unused features; + int __maybe_unused ret; + + if (!fs_info) + return; + + /* + * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not + * safe when called from some contexts (eg. balance) + */ + features = get_features(fs_info, set); + ASSERT(bit & supported_feature_masks[set]); + + fs_devs = fs_info->fs_devices; + fsid_kobj = &fs_devs->fsid_kobj; + + if (!fsid_kobj->state_initialized) + return; + + /* + * FIXME: this is too heavy to update just one value, ideally we'd like + * to use sysfs_update_group but some refactoring is needed first. + */ + sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group); + ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group); +} + +int __init btrfs_init_sysfs(void) +{ + int ret; + + btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); + if (!btrfs_kset) + return -ENOMEM; + + init_feature_attrs(); + ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); + if (ret) + goto out2; + ret = sysfs_merge_group(&btrfs_kset->kobj, + &btrfs_static_feature_attr_group); + if (ret) + goto out_remove_group; + +#ifdef CONFIG_BTRFS_DEBUG + ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); + if (ret) { + sysfs_unmerge_group(&btrfs_kset->kobj, + &btrfs_static_feature_attr_group); + goto out_remove_group; + } +#endif + + return 0; + +out_remove_group: + sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); +out2: + kset_unregister(btrfs_kset); + + return ret; +} + +void __cold btrfs_exit_sysfs(void) +{ + sysfs_unmerge_group(&btrfs_kset->kobj, + &btrfs_static_feature_attr_group); + sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); +#ifdef CONFIG_BTRFS_DEBUG + sysfs_remove_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group); +#endif + kset_unregister(btrfs_kset); +} + |