// 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" #include "misc.h" /* * Structure name Path * -------------------------------------------------------------------------- * btrfs_supported_static_feature_attrs /sys/fs/btrfs/features * btrfs_supported_feature_attrs /sys/fs/btrfs/features and * /sys/fs/btrfs/<uuid>/features * btrfs_attrs /sys/fs/btrfs/<uuid> * devid_attrs /sys/fs/btrfs/<uuid>/devinfo/<devid> * allocation_attrs /sys/fs/btrfs/<uuid>/allocation * qgroup_attrs /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid> * space_info_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type> * raid_attrs /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile> * * When built with BTRFS_CONFIG_DEBUG: * * btrfs_debug_feature_attrs /sys/fs/btrfs/debug * btrfs_debug_mount_attrs /sys/fs/btrfs/<uuid>/debug * discard_debug_attrs /sys/fs/btrfs/<uuid>/debug/discard */ 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_W(_prefix, _name, _store) \ static struct kobj_attribute btrfs_attr_##_prefix##_##_name = \ __INIT_KOBJ_ATTR(_name, 0200, NULL, _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 kobject *get_btrfs_kobj(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 sysfs_emit(buf, "%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(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(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); #ifdef CONFIG_BLK_DEV_ZONED BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED); #endif #ifdef CONFIG_BTRFS_DEBUG /* Remove once support for extent tree v2 is feature complete */ BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2); #endif #ifdef CONFIG_FS_VERITY BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY); #endif /* * Features which depend on feature bits and may differ between each fs. * * /sys/fs/btrfs/features - all available features implemented by this version * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or * can be changed on a mounted filesystem. */ static struct attribute *btrfs_supported_feature_attrs[] = { 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(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), #ifdef CONFIG_BLK_DEV_ZONED BTRFS_FEAT_ATTR_PTR(zoned), #endif #ifdef CONFIG_BTRFS_DEBUG BTRFS_FEAT_ATTR_PTR(extent_tree_v2), #endif #ifdef CONFIG_FS_VERITY BTRFS_FEAT_ATTR_PTR(verity), #endif NULL }; 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 sysfs_emit(buf, "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 += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "), btrfs_super_csum_name(i)); } ret += sysfs_emit_at(buf, 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 sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION); } BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show); static const char *rescue_opts[] = { "usebackuproot", "nologreplay", "ignorebadroots", "ignoredatacsums", "all", }; static ssize_t supported_rescue_options_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { ssize_t ret = 0; int i; for (i = 0; i < ARRAY_SIZE(rescue_opts); i++) ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]); ret += sysfs_emit_at(buf, ret, "\n"); return ret; } BTRFS_ATTR(static_feature, supported_rescue_options, supported_rescue_options_show); static ssize_t supported_sectorsizes_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { ssize_t ret = 0; /* An artificial limit to only support 4K and PAGE_SIZE */ if (PAGE_SIZE > SZ_4K) ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K); ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE); return ret; } BTRFS_ATTR(static_feature, supported_sectorsizes, supported_sectorsizes_show); /* * Features which only depend on kernel version. * * These are listed in /sys/fs/btrfs/features along with * btrfs_supported_feature_attrs. */ 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), BTRFS_ATTR_PTR(static_feature, supported_rescue_options), BTRFS_ATTR_PTR(static_feature, supported_sectorsizes), NULL }; 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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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); btrfs_discard_calc_delay(discard_ctl); btrfs_discard_schedule_work(discard_ctl, true); 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 sysfs_emit(buf, "%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); btrfs_discard_schedule_work(discard_ctl, true); 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 sysfs_emit(buf, "%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); /* * Per-filesystem debugging of discard (when mounted with discard=async). * * Path: /sys/fs/btrfs/<uuid>/debug/discard/ */ 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, }; /* * Per-filesystem runtime debugging exported via sysfs. * * Path: /sys/fs/btrfs/UUID/debug/ */ static const struct attribute *btrfs_debug_mount_attrs[] = { NULL, }; /* * Runtime debugging exported via sysfs, applies to all mounted filesystems. * * Path: /sys/fs/btrfs/debug */ 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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%llu\n", val); } /* * Allocation information about block group profiles. * * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>/ */ 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_chunk_size_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_space_info *sinfo = to_space_info(kobj); return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size)); } /* * Store new chunk size in space info. Can be called on a read-only filesystem. * * If the new chunk size value is larger than 10% of free space it is reduced * to match that limit. Alignment must be to 256M and the system chunk size * cannot be set. */ static ssize_t btrfs_chunk_size_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_space_info *space_info = to_space_info(kobj); struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); char *retptr; u64 val; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!fs_info->fs_devices) return -EINVAL; if (btrfs_is_zoned(fs_info)) return -EINVAL; /* System block type must not be changed. */ if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM) return -EPERM; val = memparse(buf, &retptr); /* There could be trailing '\n', also catch any typos after the value */ retptr = skip_spaces(retptr); if (*retptr != 0 || val == 0) return -EINVAL; val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE); /* Limit stripe size to 10% of available space. */ val = min(div_factor(fs_info->fs_devices->total_rw_bytes, 1), val); /* Must be multiple of 256M. */ val &= ~((u64)SZ_256M - 1); /* Must be at least 256M. */ if (val < SZ_256M) return -EINVAL; btrfs_update_space_info_chunk_size(space_info, val); return len; } #ifdef CONFIG_BTRFS_DEBUG /* * Request chunk allocation with current chunk size. */ static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_space_info *space_info = to_space_info(kobj); struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj)); struct btrfs_trans_handle *trans; bool val; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (sb_rdonly(fs_info->sb)) return -EROFS; ret = kstrtobool(buf, &val); if (ret) return ret; if (!val) return -EINVAL; /* * This is unsafe to be called from sysfs context and may cause * unexpected problems. */ trans = btrfs_start_transaction(fs_info->tree_root, 0); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_force_chunk_alloc(trans, space_info->flags); btrfs_end_transaction(trans); if (ret == 1) return len; return -ENOSPC; } BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store); #endif 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(bytes_zone_unusable); SPACE_INFO_ATTR(disk_used); SPACE_INFO_ATTR(disk_total); BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store); static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_space_info *space_info = to_space_info(kobj); ssize_t ret; ret = sysfs_emit(buf, "%d\n", READ_ONCE(space_info->bg_reclaim_threshold)); return ret; } static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_space_info *space_info = to_space_info(kobj); int thresh; int ret; ret = kstrtoint(buf, 10, &thresh); if (ret) return ret; if (thresh < 0 || thresh > 100) return -EINVAL; WRITE_ONCE(space_info->bg_reclaim_threshold, thresh); return len; } BTRFS_ATTR_RW(space_info, bg_reclaim_threshold, btrfs_sinfo_bg_reclaim_threshold_show, btrfs_sinfo_bg_reclaim_threshold_store); /* * Allocation information about block group types. * * Path: /sys/fs/btrfs/<uuid>/allocation/<bg-type>/ */ 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, bytes_zone_unusable), BTRFS_ATTR_PTR(space_info, disk_used), BTRFS_ATTR_PTR(space_info, disk_total), BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold), BTRFS_ATTR_PTR(space_info, chunk_size), #ifdef CONFIG_BTRFS_DEBUG BTRFS_ATTR_PTR(space_info, force_chunk_alloc), #endif NULL, }; ATTRIBUTE_GROUPS(space_info); static void space_info_release(struct kobject *kobj) { struct btrfs_space_info *sinfo = to_space_info(kobj); kfree(sinfo); } static struct kobj_type space_info_ktype = { .sysfs_ops = &kobj_sysfs_ops, .release = space_info_release, .default_groups = space_info_groups, }; /* * Allocation information about block groups. * * Path: /sys/fs/btrfs/<uuid>/allocation/ */ 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 = sysfs_emit(buf, 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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize); } BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show); static ssize_t btrfs_commit_stats_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_fs_info *fs_info = to_fs_info(kobj); return sysfs_emit(buf, "commits %llu\n" "last_commit_ms %llu\n" "max_commit_ms %llu\n" "total_commit_ms %llu\n", fs_info->commit_stats.commit_count, div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC), div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC), div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC)); } static ssize_t btrfs_commit_stats_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 val; int ret; if (!fs_info) return -EPERM; if (!capable(CAP_SYS_RESOURCE)) return -EPERM; ret = kstrtoul(buf, 10, &val); if (ret) return ret; if (val) return -EINVAL; WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0); return len; } BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store); 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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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_BALANCE_PAUSED: str = "balance paused\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 sysfs_emit(buf, "%s", str); } BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show); static ssize_t btrfs_generation_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_fs_info *fs_info = to_fs_info(kobj); return sysfs_emit(buf, "%llu\n", fs_info->generation); } BTRFS_ATTR(, generation, btrfs_generation_show); /* * Look for an exact string @string in @buffer with possible leading or * trailing whitespace */ static bool strmatch(const char *buffer, const char *string) { const size_t len = strlen(string); /* Skip leading whitespace */ buffer = skip_spaces(buffer); /* Match entire string, check if the rest is whitespace or empty */ if (strncmp(string, buffer, len) == 0 && strlen(skip_spaces(buffer + len)) == 0) return true; return false; } static const char * const btrfs_read_policy_name[] = { "pid" }; static ssize_t btrfs_read_policy_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); ssize_t ret = 0; int i; for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { if (fs_devices->read_policy == i) ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s[%s]", (ret == 0 ? "" : " "), btrfs_read_policy_name[i]); else ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s", (ret == 0 ? "" : " "), btrfs_read_policy_name[i]); } ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n"); return ret; } static ssize_t btrfs_read_policy_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj); int i; for (i = 0; i < BTRFS_NR_READ_POLICY; i++) { if (strmatch(buf, btrfs_read_policy_name[i])) { if (i != fs_devices->read_policy) { fs_devices->read_policy = i; btrfs_info(fs_devices->fs_info, "read policy set to '%s'", btrfs_read_policy_name[i]); } return len; } } return -EINVAL; } BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store); static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_fs_info *fs_info = to_fs_info(kobj); ssize_t ret; ret = sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold)); return ret; } static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_fs_info *fs_info = to_fs_info(kobj); int thresh; int ret; ret = kstrtoint(buf, 10, &thresh); if (ret) return ret; if (thresh != 0 && (thresh <= 50 || thresh > 100)) return -EINVAL; WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh); return len; } BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show, btrfs_bg_reclaim_threshold_store); /* * Per-filesystem information and stats. * * Path: /sys/fs/btrfs/<uuid>/ */ 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), BTRFS_ATTR_PTR(, generation), BTRFS_ATTR_PTR(, read_policy), BTRFS_ATTR_PTR(, bg_reclaim_threshold), BTRFS_ATTR_PTR(, commit_stats), 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; } static struct kobject *get_btrfs_kobj(struct kobject *kobj) { while (kobj) { if (kobj->ktype == &btrfs_ktype) return kobj; kobj = kobj->parent; } return NULL; } #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_assert(ARRAY_SIZE(btrfs_unknown_feature_names) == ARRAY_SIZE(btrfs_feature_attrs)); static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) == ARRAY_SIZE(btrfs_feature_attrs[0])); 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; 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 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) sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%d\n", val); } BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show); static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_device *device = container_of(kobj, struct btrfs_device, devid_kobj); return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max)); } static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj, struct kobj_attribute *a, const char *buf, size_t len) { struct btrfs_device *device = container_of(kobj, struct btrfs_device, devid_kobj); char *endptr; unsigned long long limit; limit = memparse(buf, &endptr); WRITE_ONCE(device->scrub_speed_max, limit); return len; } BTRFS_ATTR_RW(devid, scrub_speed_max, btrfs_devinfo_scrub_speed_max_show, btrfs_devinfo_scrub_speed_max_store); 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 sysfs_emit(buf, "%d\n", val); } BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show); static ssize_t btrfs_devinfo_fsid_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_device *device = container_of(kobj, struct btrfs_device, devid_kobj); return sysfs_emit(buf, "%pU\n", device->fs_devices->fsid); } BTRFS_ATTR(devid, fsid, btrfs_devinfo_fsid_show); static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) { struct btrfs_device *device = container_of(kobj, struct btrfs_device, devid_kobj); if (!device->dev_stats_valid) return sysfs_emit(buf, "invalid\n"); /* * Print all at once so we get a snapshot of all values from the same * time. Keep them in sync and in order of definition of * btrfs_dev_stat_values. */ return sysfs_emit(buf, "write_errs %d\n" "read_errs %d\n" "flush_errs %d\n" "corruption_errs %d\n" "generation_errs %d\n", btrfs_dev_stat_read(device, BTRFS_DEV_STAT_WRITE_ERRS), btrfs_dev_stat_read(device, BTRFS_DEV_STAT_READ_ERRS), btrfs_dev_stat_read(device, BTRFS_DEV_STAT_FLUSH_ERRS), btrfs_dev_stat_read(device, BTRFS_DEV_STAT_CORRUPTION_ERRS), btrfs_dev_stat_read(device, BTRFS_DEV_STAT_GENERATION_ERRS)); } BTRFS_ATTR(devid, error_stats, btrfs_devinfo_error_stats_show); /* * Information about one device. * * Path: /sys/fs/btrfs/<uuid>/devinfo/<devid>/ */ static struct attribute *devid_attrs[] = { BTRFS_ATTR_PTR(devid, error_stats), BTRFS_ATTR_PTR(devid, fsid), BTRFS_ATTR_PTR(devid, in_fs_metadata), BTRFS_ATTR_PTR(devid, missing), BTRFS_ATTR_PTR(devid, replace_target), BTRFS_ATTR_PTR(devid, scrub_speed_max), 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 kobject *disk_kobj = bdev_kobj(device->bdev); 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); /* * Qgroup information. * * Path: /sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>/ */ 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) goto out2; #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); }