diff options
Diffstat (limited to 'libbcachefs/bcachefs_ioctl.h')
| -rw-r--r-- | libbcachefs/bcachefs_ioctl.h | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/libbcachefs/bcachefs_ioctl.h b/libbcachefs/bcachefs_ioctl.h index 6578847b..73e5d887 100644 --- a/libbcachefs/bcachefs_ioctl.h +++ b/libbcachefs/bcachefs_ioctl.h @@ -5,6 +5,9 @@ #include <asm/ioctl.h> #include "bcachefs_format.h" +/* + * Flags common to multiple ioctls: + */ #define BCH_FORCE_IF_DATA_LOST (1 << 0) #define BCH_FORCE_IF_METADATA_LOST (1 << 1) #define BCH_FORCE_IF_DATA_DEGRADED (1 << 2) @@ -14,12 +17,23 @@ (BCH_FORCE_IF_DATA_DEGRADED| \ BCH_FORCE_IF_METADATA_DEGRADED) +/* + * If cleared, ioctl that refer to a device pass it as a pointer to a pathname + * (e.g. /dev/sda1); if set, the dev field is the device's index within the + * filesystem: + */ #define BCH_BY_INDEX (1 << 4) +/* + * For BCH_IOCTL_READ_SUPER: get superblock of a specific device, not filesystem + * wide superblock: + */ #define BCH_READ_DEV (1 << 5) /* global control dev: */ +/* These are currently broken, and probably unnecessary: */ +#if 0 #define BCH_IOCTL_ASSEMBLE _IOW(0xbc, 1, struct bch_ioctl_assemble) #define BCH_IOCTL_INCREMENTAL _IOW(0xbc, 2, struct bch_ioctl_incremental) @@ -35,12 +49,18 @@ struct bch_ioctl_incremental { __u64 pad; __u64 dev; }; +#endif /* filesystem ioctls: */ #define BCH_IOCTL_QUERY_UUID _IOR(0xbc, 1, struct bch_ioctl_query_uuid) + +/* These only make sense when we also have incremental assembly */ +#if 0 #define BCH_IOCTL_START _IOW(0xbc, 2, struct bch_ioctl_start) #define BCH_IOCTL_STOP _IO(0xbc, 3) +#endif + #define BCH_IOCTL_DISK_ADD _IOW(0xbc, 4, struct bch_ioctl_disk) #define BCH_IOCTL_DISK_REMOVE _IOW(0xbc, 5, struct bch_ioctl_disk) #define BCH_IOCTL_DISK_ONLINE _IOW(0xbc, 6, struct bch_ioctl_disk) @@ -52,14 +72,70 @@ struct bch_ioctl_incremental { #define BCH_IOCTL_DISK_GET_IDX _IOW(0xbc, 13, struct bch_ioctl_disk_get_idx) #define BCH_IOCTL_DISK_RESIZE _IOW(0xbc, 13, struct bch_ioctl_disk_resize) +/* + * BCH_IOCTL_QUERY_UUID: get filesystem UUID + * + * Returns user visible UUID, not internal UUID (which may not ever be changed); + * the filesystem's sysfs directory may be found under /sys/fs/bcachefs with + * this UUID. + */ struct bch_ioctl_query_uuid { uuid_le uuid; }; +#if 0 struct bch_ioctl_start { __u32 flags; __u32 pad; }; +#endif + +/* + * BCH_IOCTL_DISK_ADD: add a new device to an existing filesystem + * + * The specified device must not be open or in use. On success, the new device + * will be an online member of the filesystem just like any other member. + * + * The device must first be prepared by userspace by formatting with a bcachefs + * superblock, which is only used for passing in superblock options/parameters + * for that device (in struct bch_member). The new device's superblock should + * not claim to be a member of any existing filesystem - UUIDs on it will be + * ignored. + */ + +/* + * BCH_IOCTL_DISK_REMOVE: permanently remove a member device from a filesystem + * + * Any data present on @dev will be permanently deleted, and @dev will be + * removed from its slot in the filesystem's list of member devices. The device + * may be either offline or offline. + * + * Will fail removing @dev would leave us with insufficient read write devices + * or degraded/unavailable data, unless the approprate BCH_FORCE_IF_* flags are + * set. + */ + +/* + * BCH_IOCTL_DISK_ONLINE: given a disk that is already a member of a filesystem + * but is not open (e.g. because we started in degraded mode), bring it online + * + * all existing data on @dev will be available once the device is online, + * exactly as if @dev was present when the filesystem was first mounted + */ + +/* + * BCH_IOCTL_DISK_OFFLINE: offline a disk, causing the kernel to close that + * block device, without removing it from the filesystem (so it can be brought + * back online later) + * + * Data present on @dev will be unavailable while @dev is offline (unless + * replicated), but will still be intact and untouched if @dev is brought back + * online + * + * Will fail (similarly to BCH_IOCTL_DISK_SET_STATE) if offlining @dev would + * leave us with insufficient read write devices or degraded/unavailable data, + * unless the approprate BCH_FORCE_IF_* flags are set. + */ struct bch_ioctl_disk { __u32 flags; @@ -67,6 +143,16 @@ struct bch_ioctl_disk { __u64 dev; }; +/* + * BCH_IOCTL_DISK_SET_STATE: modify state of a member device of a filesystem + * + * @new_state - one of the bch_member_state states (rw, ro, failed, + * spare) + * + * Will refuse to change member state if we would then have insufficient devices + * to write to, or if it would result in degraded data (when @new_state is + * failed or spare) unless the appropriate BCH_FORCE_IF_* flags are set. + */ struct bch_ioctl_disk_set_state { __u32 flags; __u8 new_state; @@ -81,6 +167,15 @@ enum bch_data_ops { BCH_DATA_OP_NR = 3, }; +/* + * BCH_IOCTL_DATA: operations that walk and manipulate filesystem data (e.g. + * scrub, rereplicate, migrate). + * + * This ioctl kicks off a job in the background, and returns a file descriptor. + * Reading from the file descriptor returns a struct bch_ioctl_data_event, + * indicating current progress, and closing the file descriptor will stop the + * job. The file descriptor is O_CLOEXEC. + */ struct bch_ioctl_data { __u32 op; __u32 flags; @@ -93,9 +188,18 @@ struct bch_ioctl_data { __u32 dev; __u32 pad; } migrate; + struct { + __u64 pad[8]; + }; }; } __attribute__((packed, aligned(8))); +enum bch_data_event { + BCH_DATA_EVENT_PROGRESS = 0, + /* XXX: add an event for reporting errors */ + BCH_DATA_EVENT_NR = 1, +}; + struct bch_ioctl_data_progress { __u8 data_type; __u8 btree_id; @@ -106,6 +210,15 @@ struct bch_ioctl_data_progress { __u64 sectors_total; } __attribute__((packed, aligned(8))); +struct bch_ioctl_data_event { + __u8 type; + __u8 pad[7]; + union { + struct bch_ioctl_data_progress p; + __u64 pad2[15]; + }; +} __attribute__((packed, aligned(8))); + struct bch_ioctl_dev_usage { __u8 state; __u8 alive; @@ -127,6 +240,19 @@ struct bch_ioctl_fs_usage { __u64 sectors[BCH_DATA_NR][BCH_REPLICAS_MAX]; }; +/* + * BCH_IOCTL_USAGE: query filesystem disk space usage + * + * Returns disk space usage broken out by data type, number of replicas, and + * by component device + * + * @nr_devices - number of devices userspace allocated space for in @devs + * + * On success, @fs and @devs will be filled out appropriately and devs[i].alive + * will indicate if a device was present in that slot + * + * Returns -ERANGE if @nr_devices was too small + */ struct bch_ioctl_usage { __u16 nr_devices; __u16 pad[3]; @@ -135,6 +261,20 @@ struct bch_ioctl_usage { struct bch_ioctl_dev_usage devs[0]; }; +/* + * BCH_IOCTL_READ_SUPER: read filesystem superblock + * + * Equivalent to reading the superblock directly from the block device, except + * avoids racing with the kernel writing the superblock or having to figure out + * which block device to read + * + * @sb - buffer to read into + * @size - size of userspace allocated buffer + * @dev - device to read superblock for, if BCH_READ_DEV flag is + * specified + * + * Returns -ERANGE if buffer provided is too small + */ struct bch_ioctl_read_super { __u32 flags; __u32 pad; @@ -143,10 +283,22 @@ struct bch_ioctl_read_super { __u64 sb; }; +/* + * BCH_IOCTL_DISK_GET_IDX: give a path to a block device, query filesystem to + * determine if disk is a (online) member - if so, returns device's index + * + * Returns -ENOENT if not found + */ struct bch_ioctl_disk_get_idx { __u64 dev; }; +/* + * BCH_IOCTL_DISK_RESIZE: resize filesystem on a device + * + * @dev - member to resize + * @nbuckets - new number of buckets + */ struct bch_ioctl_disk_resize { __u32 flags; __u32 pad; |