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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Copyright (C) 2007 Oracle.  All rights reserved.4 */5 6#ifndef BTRFS_VOLUMES_H7#define BTRFS_VOLUMES_H8 9#include <linux/blk_types.h>10#include <linux/sizes.h>11#include <linux/atomic.h>12#include <linux/sort.h>13#include <linux/list.h>14#include <linux/mutex.h>15#include <linux/log2.h>16#include <linux/kobject.h>17#include <linux/refcount.h>18#include <linux/completion.h>19#include <linux/rbtree.h>20#include <uapi/linux/btrfs.h>21#include "messages.h"22#include "rcu-string.h"23 24struct block_device;25struct bdev_handle;26struct btrfs_fs_info;27struct btrfs_block_group;28struct btrfs_trans_handle;29struct btrfs_zoned_device_info;30 31#define BTRFS_MAX_DATA_CHUNK_SIZE	(10ULL * SZ_1G)32 33/*34 * Arbitratry maximum size of one discard request to limit potentially long time35 * spent in blkdev_issue_discard().36 */37#define BTRFS_MAX_DISCARD_CHUNK_SIZE	(SZ_1G)38 39extern struct mutex uuid_mutex;40 41#define BTRFS_STRIPE_LEN		SZ_64K42#define BTRFS_STRIPE_LEN_SHIFT		(16)43#define BTRFS_STRIPE_LEN_MASK		(BTRFS_STRIPE_LEN - 1)44 45static_assert(const_ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT);46 47/* Used by sanity check for btrfs_raid_types. */48#define const_ffs(n) (__builtin_ctzll(n) + 1)49 50/*51 * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires52 * RAID0 always to be the lowest profile bit.53 * Although it's part of on-disk format and should never change, do extra54 * compile-time sanity checks.55 */56static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) <57	      const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0));58static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) >59	      ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK));60 61/* ilog2() can handle both constants and variables */62#define BTRFS_BG_FLAG_TO_INDEX(profile)					\63	ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1))64 65enum btrfs_raid_types {66	/* SINGLE is the special one as it doesn't have on-disk bit. */67	BTRFS_RAID_SINGLE  = 0,68 69	BTRFS_RAID_RAID0   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0),70	BTRFS_RAID_RAID1   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1),71	BTRFS_RAID_DUP	   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP),72	BTRFS_RAID_RAID10  = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10),73	BTRFS_RAID_RAID5   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5),74	BTRFS_RAID_RAID6   = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6),75	BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3),76	BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4),77 78	BTRFS_NR_RAID_TYPES79};80 81/*82 * Use sequence counter to get consistent device stat data on83 * 32-bit processors.84 */85#if BITS_PER_LONG==32 && defined(CONFIG_SMP)86#include <linux/seqlock.h>87#define __BTRFS_NEED_DEVICE_DATA_ORDERED88#define btrfs_device_data_ordered_init(device)	\89	seqcount_init(&device->data_seqcount)90#else91#define btrfs_device_data_ordered_init(device) do { } while (0)92#endif93 94#define BTRFS_DEV_STATE_WRITEABLE	(0)95#define BTRFS_DEV_STATE_IN_FS_METADATA	(1)96#define BTRFS_DEV_STATE_MISSING		(2)97#define BTRFS_DEV_STATE_REPLACE_TGT	(3)98#define BTRFS_DEV_STATE_FLUSH_SENT	(4)99#define BTRFS_DEV_STATE_NO_READA	(5)100 101/* Special value encoding failure to write primary super block. */102#define BTRFS_SUPER_PRIMARY_WRITE_ERROR		(INT_MAX / 2)103 104struct btrfs_fs_devices;105 106struct btrfs_device {107	struct list_head dev_list; /* device_list_mutex */108	struct list_head dev_alloc_list; /* chunk mutex */109	struct list_head post_commit_list; /* chunk mutex */110	struct btrfs_fs_devices *fs_devices;111	struct btrfs_fs_info *fs_info;112 113	struct rcu_string __rcu *name;114 115	u64 generation;116 117	struct file *bdev_file;118	struct block_device *bdev;119 120	struct btrfs_zoned_device_info *zone_info;121 122	/*123	 * Device's major-minor number. Must be set even if the device is not124	 * opened (bdev == NULL), unless the device is missing.125	 */126	dev_t devt;127	unsigned long dev_state;128	blk_status_t last_flush_error;129 130#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED131	seqcount_t data_seqcount;132#endif133 134	/* the internal btrfs device id */135	u64 devid;136 137	/* size of the device in memory */138	u64 total_bytes;139 140	/* size of the device on disk */141	u64 disk_total_bytes;142 143	/* bytes used */144	u64 bytes_used;145 146	/* optimal io alignment for this device */147	u32 io_align;148 149	/* optimal io width for this device */150	u32 io_width;151	/* type and info about this device */152	u64 type;153 154	/*155	 * Counter of super block write errors, values larger than156	 * BTRFS_SUPER_PRIMARY_WRITE_ERROR encode primary super block write failure.157	 */158	atomic_t sb_write_errors;159 160	/* minimal io size for this device */161	u32 sector_size;162 163	/* physical drive uuid (or lvm uuid) */164	u8 uuid[BTRFS_UUID_SIZE];165 166	/*167	 * size of the device on the current transaction168	 *169	 * This variant is update when committing the transaction,170	 * and protected by chunk mutex171	 */172	u64 commit_total_bytes;173 174	/* bytes used on the current transaction */175	u64 commit_bytes_used;176 177	/* Bio used for flushing device barriers */178	struct bio flush_bio;179	struct completion flush_wait;180 181	/* per-device scrub information */182	struct scrub_ctx *scrub_ctx;183 184	/* disk I/O failure stats. For detailed description refer to185	 * enum btrfs_dev_stat_values in ioctl.h */186	int dev_stats_valid;187 188	/* Counter to record the change of device stats */189	atomic_t dev_stats_ccnt;190	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];191 192	struct extent_io_tree alloc_state;193 194	struct completion kobj_unregister;195	/* For sysfs/FSID/devinfo/devid/ */196	struct kobject devid_kobj;197 198	/* Bandwidth limit for scrub, in bytes */199	u64 scrub_speed_max;200};201 202/*203 * Block group or device which contains an active swapfile. Used for preventing204 * unsafe operations while a swapfile is active.205 *206 * These are sorted on (ptr, inode) (note that a block group or device can207 * contain more than one swapfile). We compare the pointer values because we208 * don't actually care what the object is, we just need a quick check whether209 * the object exists in the rbtree.210 */211struct btrfs_swapfile_pin {212	struct rb_node node;213	void *ptr;214	struct inode *inode;215	/*216	 * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr217	 * points to a struct btrfs_device.218	 */219	bool is_block_group;220	/*221	 * Only used when 'is_block_group' is true and it is the number of222	 * extents used by a swapfile for this block group ('ptr' field).223	 */224	int bg_extent_count;225};226 227/*228 * If we read those variants at the context of their own lock, we needn't229 * use the following helpers, reading them directly is safe.230 */231#if BITS_PER_LONG==32 && defined(CONFIG_SMP)232#define BTRFS_DEVICE_GETSET_FUNCS(name)					\233static inline u64							\234btrfs_device_get_##name(const struct btrfs_device *dev)			\235{									\236	u64 size;							\237	unsigned int seq;						\238									\239	do {								\240		seq = read_seqcount_begin(&dev->data_seqcount);		\241		size = dev->name;					\242	} while (read_seqcount_retry(&dev->data_seqcount, seq));	\243	return size;							\244}									\245									\246static inline void							\247btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\248{									\249	preempt_disable();						\250	write_seqcount_begin(&dev->data_seqcount);			\251	dev->name = size;						\252	write_seqcount_end(&dev->data_seqcount);			\253	preempt_enable();						\254}255#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)256#define BTRFS_DEVICE_GETSET_FUNCS(name)					\257static inline u64							\258btrfs_device_get_##name(const struct btrfs_device *dev)			\259{									\260	u64 size;							\261									\262	preempt_disable();						\263	size = dev->name;						\264	preempt_enable();						\265	return size;							\266}									\267									\268static inline void							\269btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\270{									\271	preempt_disable();						\272	dev->name = size;						\273	preempt_enable();						\274}275#else276#define BTRFS_DEVICE_GETSET_FUNCS(name)					\277static inline u64							\278btrfs_device_get_##name(const struct btrfs_device *dev)			\279{									\280	return dev->name;						\281}									\282									\283static inline void							\284btrfs_device_set_##name(struct btrfs_device *dev, u64 size)		\285{									\286	dev->name = size;						\287}288#endif289 290BTRFS_DEVICE_GETSET_FUNCS(total_bytes);291BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);292BTRFS_DEVICE_GETSET_FUNCS(bytes_used);293 294enum btrfs_chunk_allocation_policy {295	BTRFS_CHUNK_ALLOC_REGULAR,296	BTRFS_CHUNK_ALLOC_ZONED,297};298 299/*300 * Read policies for mirrored block group profiles, read picks the stripe based301 * on these policies.302 */303enum btrfs_read_policy {304	/* Use process PID to choose the stripe */305	BTRFS_READ_POLICY_PID,306	BTRFS_NR_READ_POLICY,307};308 309#ifdef CONFIG_BTRFS_DEBUG310/*311 * Checksum mode - offload it to workqueues or do it synchronously in312 * btrfs_submit_chunk().313 */314enum btrfs_offload_csum_mode {315	/*316	 * Choose offloading checksum or do it synchronously automatically.317	 * Do it synchronously if the checksum is fast, or offload to workqueues318	 * otherwise.319	 */320	BTRFS_OFFLOAD_CSUM_AUTO,321	/* Always offload checksum to workqueues. */322	BTRFS_OFFLOAD_CSUM_FORCE_ON,323	/* Never offload checksum to workqueues. */324	BTRFS_OFFLOAD_CSUM_FORCE_OFF,325};326#endif327 328struct btrfs_fs_devices {329	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */330 331	/*332	 * UUID written into the btree blocks:333	 *334	 * - If metadata_uuid != fsid then super block must have335	 *   BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set.336	 *337	 * - Following shall be true at all times:338	 *   - metadata_uuid == btrfs_header::fsid339	 *   - metadata_uuid == btrfs_dev_item::fsid340	 *341	 * - Relations between fsid and metadata_uuid in sb and fs_devices:342	 *   - Normal:343	 *       fs_devices->fsid == fs_devices->metadata_uuid == sb->fsid344	 *       sb->metadata_uuid == 0345	 *346	 *   - When the BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag is set:347	 *       fs_devices->fsid == sb->fsid348	 *       fs_devices->metadata_uuid == sb->metadata_uuid349	 *350	 *   - When in-memory fs_devices->temp_fsid is true351	 *	 fs_devices->fsid = random352	 *	 fs_devices->metadata_uuid == sb->fsid353	 */354	u8 metadata_uuid[BTRFS_FSID_SIZE];355 356	struct list_head fs_list;357 358	/*359	 * Number of devices under this fsid including missing and360	 * replace-target device and excludes seed devices.361	 */362	u64 num_devices;363 364	/*365	 * The number of devices that successfully opened, including366	 * replace-target, excludes seed devices.367	 */368	u64 open_devices;369 370	/* The number of devices that are under the chunk allocation list. */371	u64 rw_devices;372 373	/* Count of missing devices under this fsid excluding seed device. */374	u64 missing_devices;375	u64 total_rw_bytes;376 377	/*378	 * Count of devices from btrfs_super_block::num_devices for this fsid,379	 * which includes the seed device, excludes the transient replace-target380	 * device.381	 */382	u64 total_devices;383 384	/* Highest generation number of seen devices */385	u64 latest_generation;386 387	/*388	 * The mount device or a device with highest generation after removal389	 * or replace.390	 */391	struct btrfs_device *latest_dev;392 393	/*394	 * All of the devices in the filesystem, protected by a mutex so we can395	 * safely walk it to write out the super blocks without worrying about396	 * adding/removing by the multi-device code. Scrubbing super block can397	 * kick off supers writing by holding this mutex lock.398	 */399	struct mutex device_list_mutex;400 401	/* List of all devices, protected by device_list_mutex */402	struct list_head devices;403 404	/* Devices which can satisfy space allocation. Protected by * chunk_mutex. */405	struct list_head alloc_list;406 407	struct list_head seed_list;408 409	/* Count fs-devices opened. */410	int opened;411 412	/* Set when we find or add a device that doesn't have the nonrot flag set. */413	bool rotating;414	/* Devices support TRIM/discard commands. */415	bool discardable;416	/* The filesystem is a seed filesystem. */417	bool seeding;418	/* The mount needs to use a randomly generated fsid. */419	bool temp_fsid;420 421	struct btrfs_fs_info *fs_info;422	/* sysfs kobjects */423	struct kobject fsid_kobj;424	struct kobject *devices_kobj;425	struct kobject *devinfo_kobj;426	struct completion kobj_unregister;427 428	enum btrfs_chunk_allocation_policy chunk_alloc_policy;429 430	/* Policy used to read the mirrored stripes. */431	enum btrfs_read_policy read_policy;432 433#ifdef CONFIG_BTRFS_DEBUG434	/* Checksum mode - offload it or do it synchronously. */435	enum btrfs_offload_csum_mode offload_csum_mode;436#endif437};438 439#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info)	\440			- sizeof(struct btrfs_chunk))		\441			/ sizeof(struct btrfs_stripe) + 1)442 443#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE	\444				- 2 * sizeof(struct btrfs_disk_key)	\445				- 2 * sizeof(struct btrfs_chunk))	\446				/ sizeof(struct btrfs_stripe) + 1)447 448struct btrfs_io_stripe {449	struct btrfs_device *dev;450	/* Block mapping. */451	u64 physical;452	u64 length;453	bool rst_search_commit_root;454	/* For the endio handler. */455	struct btrfs_io_context *bioc;456};457 458struct btrfs_discard_stripe {459	struct btrfs_device *dev;460	u64 physical;461	u64 length;462};463 464/*465 * Context for IO subsmission for device stripe.466 *467 * - Track the unfinished mirrors for mirror based profiles468 *   Mirror based profiles are SINGLE/DUP/RAID1/RAID10.469 *470 * - Contain the logical -> physical mapping info471 *   Used by submit_stripe_bio() for mapping logical bio472 *   into physical device address.473 *474 * - Contain device replace info475 *   Used by handle_ops_on_dev_replace() to copy logical bios476 *   into the new device.477 *478 * - Contain RAID56 full stripe logical bytenrs479 */480struct btrfs_io_context {481	refcount_t refs;482	struct btrfs_fs_info *fs_info;483	/* Taken from struct btrfs_chunk_map::type. */484	u64 map_type;485	struct bio *orig_bio;486	atomic_t error;487	u16 max_errors;488 489	u64 logical;490	u64 size;491	/* Raid stripe tree ordered entry. */492	struct list_head rst_ordered_entry;493 494	/*495	 * The total number of stripes, including the extra duplicated496	 * stripe for replace.497	 */498	u16 num_stripes;499 500	/*501	 * The mirror_num of this bioc.502	 *503	 * This is for reads which use 0 as mirror_num, thus we should return a504	 * valid mirror_num (>0) for the reader.505	 */506	u16 mirror_num;507 508	/*509	 * The following two members are for dev-replace case only.510	 *511	 * @replace_nr_stripes:	Number of duplicated stripes which need to be512	 *			written to replace target.513	 *			Should be <= 2 (2 for DUP, otherwise <= 1).514	 * @replace_stripe_src:	The array indicates where the duplicated stripes515	 *			are from.516	 *517	 * The @replace_stripe_src[] array is mostly for RAID56 cases.518	 * As non-RAID56 stripes share the same contents of the mapped range,519	 * thus no need to bother where the duplicated ones are from.520	 *521	 * But for RAID56 case, all stripes contain different contents, thus522	 * we need a way to know the mapping.523	 *524	 * There is an example for the two members, using a RAID5 write:525	 *526	 *   num_stripes:	4 (3 + 1 duplicated write)527	 *   stripes[0]:	dev = devid 1, physical = X528	 *   stripes[1]:	dev = devid 2, physical = Y529	 *   stripes[2]:	dev = devid 3, physical = Z530	 *   stripes[3]:	dev = devid 0, physical = Y531	 *532	 * replace_nr_stripes = 1533	 * replace_stripe_src = 1	<- Means stripes[1] is involved in replace.534	 *				   The duplicated stripe index would be535	 *				   (@num_stripes - 1).536	 *537	 * Note, that we can still have cases replace_nr_stripes = 2 for DUP.538	 * In that case, all stripes share the same content, thus we don't539	 * need to bother @replace_stripe_src value at all.540	 */541	u16 replace_nr_stripes;542	s16 replace_stripe_src;543	/*544	 * Logical bytenr of the full stripe start, only for RAID56 cases.545	 *546	 * When this value is set to other than (u64)-1, the stripes[] should547	 * follow this pattern:548	 *549	 * (real_stripes = num_stripes - replace_nr_stripes)550	 * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1))551	 *552	 * stripes[0]:			The first data stripe553	 * stripes[1]:			The second data stripe554	 * ...555	 * stripes[data_stripes - 1]:	The last data stripe556	 * stripes[data_stripes]:	The P stripe557	 * stripes[data_stripes + 1]:	The Q stripe (only for RAID6).558	 */559	u64 full_stripe_logical;560	struct btrfs_io_stripe stripes[];561};562 563struct btrfs_device_info {564	struct btrfs_device *dev;565	u64 dev_offset;566	u64 max_avail;567	u64 total_avail;568};569 570struct btrfs_raid_attr {571	u8 sub_stripes;		/* sub_stripes info for map */572	u8 dev_stripes;		/* stripes per dev */573	u8 devs_max;		/* max devs to use */574	u8 devs_min;		/* min devs needed */575	u8 tolerated_failures;	/* max tolerated fail devs */576	u8 devs_increment;	/* ndevs has to be a multiple of this */577	u8 ncopies;		/* how many copies to data has */578	u8 nparity;		/* number of stripes worth of bytes to store579				 * parity information */580	u8 mindev_error;	/* error code if min devs requisite is unmet */581	const char raid_name[8]; /* name of the raid */582	u64 bg_flag;		/* block group flag of the raid */583};584 585extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];586 587struct btrfs_chunk_map {588	struct rb_node rb_node;589	/* For mount time dev extent verification. */590	int verified_stripes;591	refcount_t refs;592	u64 start;593	u64 chunk_len;594	u64 stripe_size;595	u64 type;596	int io_align;597	int io_width;598	int num_stripes;599	int sub_stripes;600	struct btrfs_io_stripe stripes[];601};602 603#define btrfs_chunk_map_size(n) (sizeof(struct btrfs_chunk_map) + \604				 (sizeof(struct btrfs_io_stripe) * (n)))605 606static inline void btrfs_free_chunk_map(struct btrfs_chunk_map *map)607{608	if (map && refcount_dec_and_test(&map->refs)) {609		ASSERT(RB_EMPTY_NODE(&map->rb_node));610		kfree(map);611	}612}613 614struct btrfs_balance_control {615	struct btrfs_balance_args data;616	struct btrfs_balance_args meta;617	struct btrfs_balance_args sys;618 619	u64 flags;620 621	struct btrfs_balance_progress stat;622};623 624/*625 * Search for a given device by the set parameters626 */627struct btrfs_dev_lookup_args {628	u64 devid;629	u8 *uuid;630	u8 *fsid;631	bool missing;632};633 634/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */635#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 }636 637#define BTRFS_DEV_LOOKUP_ARGS(name) \638	struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT639 640enum btrfs_map_op {641	BTRFS_MAP_READ,642	BTRFS_MAP_WRITE,643	BTRFS_MAP_GET_READ_MIRRORS,644};645 646static inline enum btrfs_map_op btrfs_op(struct bio *bio)647{648	switch (bio_op(bio)) {649	case REQ_OP_WRITE:650	case REQ_OP_ZONE_APPEND:651		return BTRFS_MAP_WRITE;652	default:653		WARN_ON_ONCE(1);654		fallthrough;655	case REQ_OP_READ:656		return BTRFS_MAP_READ;657	}658}659 660static inline unsigned long btrfs_chunk_item_size(int num_stripes)661{662	ASSERT(num_stripes);663	return sizeof(struct btrfs_chunk) +664		sizeof(struct btrfs_stripe) * (num_stripes - 1);665}666 667/*668 * Do the type safe conversion from stripe_nr to offset inside the chunk.669 *670 * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger671 * than 4G.  This does the proper type cast to avoid overflow.672 */673static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr)674{675	return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT;676}677 678void btrfs_get_bioc(struct btrfs_io_context *bioc);679void btrfs_put_bioc(struct btrfs_io_context *bioc);680int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,681		    u64 logical, u64 *length,682		    struct btrfs_io_context **bioc_ret,683		    struct btrfs_io_stripe *smap, int *mirror_num_ret);684int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,685			   struct btrfs_io_stripe *smap, u64 logical,686			   u32 length, int mirror_num);687struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,688					       u64 logical, u64 *length_ret,689					       u32 *num_stripes);690int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);691int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);692struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,693					    u64 type);694void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info);695int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,696		       blk_mode_t flags, void *holder);697struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,698					   bool mount_arg_dev);699int btrfs_forget_devices(dev_t devt);700void btrfs_close_devices(struct btrfs_fs_devices *fs_devices);701void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);702void btrfs_assign_next_active_device(struct btrfs_device *device,703				     struct btrfs_device *this_dev);704struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,705						  u64 devid,706						  const char *devpath);707int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,708				 struct btrfs_dev_lookup_args *args,709				 const char *path);710struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,711					const u64 *devid, const u8 *uuid,712					const char *path);713void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);714int btrfs_rm_device(struct btrfs_fs_info *fs_info,715		    struct btrfs_dev_lookup_args *args,716		    struct file **bdev_file);717void __exit btrfs_cleanup_fs_uuids(void);718int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);719int btrfs_grow_device(struct btrfs_trans_handle *trans,720		      struct btrfs_device *device, u64 new_size);721struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,722				       const struct btrfs_dev_lookup_args *args);723int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);724int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);725int btrfs_balance(struct btrfs_fs_info *fs_info,726		  struct btrfs_balance_control *bctl,727		  struct btrfs_ioctl_balance_args *bargs);728void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);729int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);730int btrfs_recover_balance(struct btrfs_fs_info *fs_info);731int btrfs_pause_balance(struct btrfs_fs_info *fs_info);732int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset);733int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);734bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset);735void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);736int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,737			struct btrfs_ioctl_get_dev_stats *stats);738int btrfs_init_devices_late(struct btrfs_fs_info *fs_info);739int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);740int btrfs_run_dev_stats(struct btrfs_trans_handle *trans);741void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);742void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);743void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);744int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,745			   u64 logical, u64 len);746unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,747				    u64 logical);748u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map);749int btrfs_nr_parity_stripes(u64 type);750int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,751				     struct btrfs_block_group *bg);752int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);753 754#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS755struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp);756int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);757#endif758 759struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,760					     u64 logical, u64 length);761struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,762						    u64 logical, u64 length);763struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,764					    u64 logical, u64 length);765void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map);766void btrfs_release_disk_super(struct btrfs_super_block *super);767 768static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,769				      int index)770{771	atomic_inc(dev->dev_stat_values + index);772	/*773	 * This memory barrier orders stores updating statistics before stores774	 * updating dev_stats_ccnt.775	 *776	 * It pairs with smp_rmb() in btrfs_run_dev_stats().777	 */778	smp_mb__before_atomic();779	atomic_inc(&dev->dev_stats_ccnt);780}781 782static inline int btrfs_dev_stat_read(struct btrfs_device *dev,783				      int index)784{785	return atomic_read(dev->dev_stat_values + index);786}787 788static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,789						int index)790{791	int ret;792 793	ret = atomic_xchg(dev->dev_stat_values + index, 0);794	/*795	 * atomic_xchg implies a full memory barriers as per atomic_t.txt:796	 * - RMW operations that have a return value are fully ordered;797	 *798	 * This implicit memory barriers is paired with the smp_rmb in799	 * btrfs_run_dev_stats800	 */801	atomic_inc(&dev->dev_stats_ccnt);802	return ret;803}804 805static inline void btrfs_dev_stat_set(struct btrfs_device *dev,806				      int index, unsigned long val)807{808	atomic_set(dev->dev_stat_values + index, val);809	/*810	 * This memory barrier orders stores updating statistics before stores811	 * updating dev_stats_ccnt.812	 *813	 * It pairs with smp_rmb() in btrfs_run_dev_stats().814	 */815	smp_mb__before_atomic();816	atomic_inc(&dev->dev_stats_ccnt);817}818 819static inline const char *btrfs_dev_name(const struct btrfs_device *device)820{821	if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))822		return "<missing disk>";823	else824		return rcu_str_deref(device->name);825}826 827void btrfs_commit_device_sizes(struct btrfs_transaction *trans);828 829struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);830bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,831					struct btrfs_device *failing_dev);832void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device);833 834enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags);835int btrfs_bg_type_to_factor(u64 flags);836const char *btrfs_bg_type_to_raid_name(u64 flags);837int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);838bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);839 840bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);841const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb);842 843#endif844