diff options
| -rw-r--r-- | Documentation/device-mapper/dm-integrity.txt | 189 | ||||
| -rw-r--r-- | drivers/md/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/md/Makefile | 1 | ||||
| -rw-r--r-- | drivers/md/dm-integrity.c | 3085 |
4 files changed, 3285 insertions, 0 deletions
diff --git a/Documentation/device-mapper/dm-integrity.txt b/Documentation/device-mapper/dm-integrity.txt new file mode 100644 index 000000000000..2406f56501dc --- /dev/null +++ b/Documentation/device-mapper/dm-integrity.txt @@ -0,0 +1,189 @@ +The dm-integrity target emulates a block device that has additional +per-sector tags that can be used for storing integrity information. + +A general problem with storing integrity tags with every sector is that +writing the sector and the integrity tag must be atomic - i.e. in case of +crash, either both sector and integrity tag or none of them is written. + +To guarantee write atomicity, the dm-integrity target uses journal, it +writes sector data and integrity tags into a journal, commits the journal +and then copies the data and integrity tags to their respective location. + +The dm-integrity target can be used with the dm-crypt target - in this +situation the dm-crypt target creates the integrity data and passes them +to the dm-integrity target via bio_integrity_payload attached to the bio. +In this mode, the dm-crypt and dm-integrity targets provide authenticated +disk encryption - if the attacker modifies the encrypted device, an I/O +error is returned instead of random data. + +The dm-integrity target can also be used as a standalone target, in this +mode it calculates and verifies the integrity tag internally. In this +mode, the dm-integrity target can be used to detect silent data +corruption on the disk or in the I/O path. + + +When loading the target for the first time, the kernel driver will format +the device. But it will only format the device if the superblock contains +zeroes. If the superblock is neither valid nor zeroed, the dm-integrity +target can't be loaded. + +To use the target for the first time: +1. overwrite the superblock with zeroes +2. load the dm-integrity target with one-sector size, the kernel driver + will format the device +3. unload the dm-integrity target +4. read the "provided_data_sectors" value from the superblock +5. load the dm-integrity target with the the target size + "provided_data_sectors" +6. if you want to use dm-integrity with dm-crypt, load the dm-crypt target + with the size "provided_data_sectors" + + +Target arguments: + +1. the underlying block device + +2. the number of reserved sector at the beginning of the device - the + dm-integrity won't read of write these sectors + +3. the size of the integrity tag (if "-" is used, the size is taken from + the internal-hash algorithm) + +4. mode: + D - direct writes (without journal) - in this mode, journaling is + not used and data sectors and integrity tags are written + separately. In case of crash, it is possible that the data + and integrity tag doesn't match. + J - journaled writes - data and integrity tags are written to the + journal and atomicity is guaranteed. In case of crash, + either both data and tag or none of them are written. The + journaled mode degrades write throughput twice because the + data have to be written twice. + +5. the number of additional arguments + +Additional arguments: + +journal-sectors:number + The size of journal, this argument is used only if formatting the + device. If the device is already formatted, the value from the + superblock is used. + +interleave-sectors:number + The number of interleaved sectors. This values is rounded down to + a power of two. If the device is already formatted, the value from + the superblock is used. + +buffer-sectors:number + The number of sectors in one buffer. The value is rounded down to + a power of two. + + The tag area is accessed using buffers, the buffer size is + configurable. The large buffer size means that the I/O size will + be larger, but there could be less I/Os issued. + +journal-watermark:number + The journal watermark in percents. When the size of the journal + exceeds this watermark, the thread that flushes the journal will + be started. + +commit-time:number + Commit time in milliseconds. When this time passes, the journal is + written. The journal is also written immediatelly if the FLUSH + request is received. + +internal-hash:algorithm(:key) (the key is optional) + Use internal hash or crc. + When this argument is used, the dm-integrity target won't accept + integrity tags from the upper target, but it will automatically + generate and verify the integrity tags. + + You can use a crc algorithm (such as crc32), then integrity target + will protect the data against accidental corruption. + You can also use a hmac algorithm (for example + "hmac(sha256):0123456789abcdef"), in this mode it will provide + cryptographic authentication of the data without encryption. + + When this argument is not used, the integrity tags are accepted + from an upper layer target, such as dm-crypt. The upper layer + target should check the validity of the integrity tags. + +journal-crypt:algorithm(:key) (the key is optional) + Encrypt the journal using given algorithm to make sure that the + attacker can't read the journal. You can use a block cipher here + (such as "cbc(aes)") or a stream cipher (for example "chacha20", + "salsa20", "ctr(aes)" or "ecb(arc4)"). + + The journal contains history of last writes to the block device, + an attacker reading the journal could see the last sector nubmers + that were written. From the sector numbers, the attacker can infer + the size of files that were written. To protect against this + situation, you can encrypt the journal. + +journal-mac:algorithm(:key) (the key is optional) + Protect sector numbers in the journal from accidental or malicious + modification. To protect against accidental modification, use a + crc algorithm, to protect against malicious modification, use a + hmac algorithm with a key. + + This option is not needed when using internal-hash because in this + mode, the integrity of journal entries is checked when replaying + the journal. Thus, modified sector number would be detected at + this stage. + + +The journal mode (D/J), buffer-sectors, journal-watermark, commit-time can +be changed when reloading the target (load an inactive table and swap the +tables with suspend and resume). The other arguments should not be changed +when reloading the target because the layout of disk data depend on them +and the reloaded target would be non-functional. + + +The layout of the formatted block device: +* reserved sectors (they are not used by this target, they can be used for + storing LUKS metadata or for other purpose), the size of the reserved + area is specified in the target arguments +* superblock (4kiB) + * magic string - identifies that the device was formatted + * version + * log2(interleave sectors) + * integrity tag size + * the number of journal sections + * provided data sectors - the number of sectors that this target + provides (i.e. the size of the device minus the size of all + metadata and padding). The user of this target should not send + bios that access data beyond the "provided data sectors" limit. + * flags - a flag is set if journal-mac is used +* journal + The journal is divided into sections, each section contains: + * metadata area (4kiB), it contains journal entries + every journal entry contains: + * logical sector (specifies where the data and tag should + be written) + * last 8 bytes of data + * integrity tag (the size is specified in the superblock) + every metadata sector ends with + * mac (8-bytes), all the macs in 8 metadata sectors form a + 64-byte value. It is used to store hmac of sector + numbers in the journal section, to protect against a + possibility that the attacker tampers with sector + numbers in the journal. + * commit id + * data area (the size is variable; it depends on how many journal + entries fit into the metadata area) + every sector in the data area contains: + * data (504 bytes of data, the last 8 bytes are stored in + the journal entry) + * commit id + To test if the whole journal section was written correctly, every + 512-byte sector of the journal ends with 8-byte commit id. If the + commit id matches on all sectors in a journal section, then it is + assumed that the section was written correctly. If the commit id + doesn't match, the section was written partially and it should not + be replayed. +* one or more runs of interleaved tags and data. Each run contains: + * tag area - it contains integrity tags. There is one tag for each + sector in the data area + * data area - it contains data sectors. The number of data sectors + in one run must be a power of two. log2 of this value is stored + in the superblock. diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 982cd0626bc7..5c5ed97c9fda 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -500,4 +500,14 @@ config DM_LOG_WRITES If unsure, say N. +config DM_INTEGRITY + tristate "Integrity target" + depends on BLK_DEV_DM + select BLK_DEV_INTEGRITY + select DM_BUFIO + select CRYPTO + select ASYNC_XOR + ---help--- + This is the integrity target. + endif # MD diff --git a/drivers/md/Makefile b/drivers/md/Makefile index 2801b2fb452d..39cf2a1b5f90 100644 --- a/drivers/md/Makefile +++ b/drivers/md/Makefile @@ -59,6 +59,7 @@ obj-$(CONFIG_DM_CACHE) += dm-cache.o obj-$(CONFIG_DM_CACHE_SMQ) += dm-cache-smq.o obj-$(CONFIG_DM_ERA) += dm-era.o obj-$(CONFIG_DM_LOG_WRITES) += dm-log-writes.o +obj-$(CONFIG_DM_INTEGRITY) += dm-integrity.o ifeq ($(CONFIG_DM_UEVENT),y) dm-mod-objs += dm-uevent.o diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c new file mode 100644 index 000000000000..ea779cca8b45 --- /dev/null +++ b/drivers/md/dm-integrity.c @@ -0,0 +1,3085 @@ +/* + * Copyright (C) 2016-2017 Red Hat, Inc. All rights reserved. + * Copyright (C) 2016-2017 Milan Broz + * Copyright (C) 2016-2017 Mikulas Patocka + * + * This file is released under the GPL. + */ + +#include <linux/module.h> +#include <linux/device-mapper.h> +#include <linux/dm-io.h> +#include <linux/vmalloc.h> +#include <linux/sort.h> +#include <linux/rbtree.h> +#include <linux/delay.h> +#include <linux/random.h> +#include <crypto/hash.h> +#include <crypto/skcipher.h> +#include <linux/async_tx.h> +#include "dm-bufio.h" + +#define DM_MSG_PREFIX "integrity" + +#define DEFAULT_INTERLEAVE_SECTORS 32768 +#define DEFAULT_JOURNAL_SIZE_FACTOR 7 +#define DEFAULT_BUFFER_SECTORS 128 +#define DEFAULT_JOURNAL_WATERMARK 50 +#define DEFAULT_SYNC_MSEC 10000 +#define DEFAULT_MAX_JOURNAL_SECTORS 131072 +#define MIN_INTERLEAVE_SECTORS 3 +#define MAX_INTERLEAVE_SECTORS 31 +#define METADATA_WORKQUEUE_MAX_ACTIVE 16 + +/* + * Warning - DEBUG_PRINT prints security-sensitive data to the log, + * so it should not be enabled in the official kernel + */ +//#define DEBUG_PRINT +//#define INTERNAL_VERIFY + +/* + * On disk structures + */ + +#define SB_MAGIC "integrt" +#define SB_VERSION 1 +#define SB_SECTORS 8 + +struct superblock { + __u8 magic[8]; + __u8 version; + __u8 log2_interleave_sectors; + __u16 integrity_tag_size; + __u32 journal_sections; + __u64 provided_data_sectors; /* userspace uses this value */ + __u32 flags; +}; + +#define SB_FLAG_HAVE_JOURNAL_MAC 0x1 + +#define JOURNAL_ENTRY_ROUNDUP 8 + +typedef __u64 commit_id_t; +#define JOURNAL_MAC_PER_SECTOR 8 + +struct journal_entry { + union { + struct { + __u32 sector_lo; + __u32 sector_hi; + } s; + __u64 sector; + } u; + commit_id_t last_bytes; + __u8 tag[0]; +}; + +#if BITS_PER_LONG == 64 +#define journal_entry_set_sector(je, x) do { smp_wmb(); ACCESS_ONCE((je)->u.sector) = cpu_to_le64(x); } while (0) +#define journal_entry_get_sector(je) le64_to_cpu((je)->u.sector) +#elif defined(CONFIG_LBDAF) +#define journal_entry_set_sector(je, x) do { (je)->u.s.sector_lo = cpu_to_le32(x); smp_wmb(); ACCESS_ONCE((je)->u.s.sector_hi) = cpu_to_le32((x) >> 32); } while (0) +#define journal_entry_get_sector(je) le64_to_cpu((je)->u.sector) +#else +#define journal_entry_set_sector(je, x) do { (je)->u.s.sector_lo = cpu_to_le32(x); smp_wmb(); ACCESS_ONCE((je)->u.s.sector_hi) = cpu_to_le32(0); } while (0) +#define journal_entry_get_sector(je) le32_to_cpu((je)->u.s.sector_lo) +#endif +#define journal_entry_is_unused(je) ((je)->u.s.sector_hi == cpu_to_le32(-1)) +#define journal_entry_set_unused(je) do { ((je)->u.s.sector_hi = cpu_to_le32(-1)); } while (0) +#define journal_entry_is_inprogress(je) ((je)->u.s.sector_hi == cpu_to_le32(-2)) +#define journal_entry_set_inprogress(je) do { ((je)->u.s.sector_hi = cpu_to_le32(-2)); } while (0) + +#define JOURNAL_BLOCK_SECTORS 8 +#define JOURNAL_SECTOR_DATA ((1 << SECTOR_SHIFT) - sizeof(commit_id_t)) +#define JOURNAL_MAC_SIZE (JOURNAL_MAC_PER_SECTOR * JOURNAL_BLOCK_SECTORS) + +struct journal_sector { + __u8 entries[JOURNAL_SECTOR_DATA - JOURNAL_MAC_PER_SECTOR]; + __u8 mac[JOURNAL_MAC_PER_SECTOR]; + commit_id_t commit_id; +}; + +#define MAX_TAG_SIZE (JOURNAL_SECTOR_DATA - JOURNAL_MAC_PER_SECTOR - offsetof(struct journal_entry, tag)) + +#define METADATA_PADDING_SECTORS 8 + +#define N_COMMIT_IDS 4 + +static unsigned char prev_commit_seq(unsigned char seq) +{ + return (seq + N_COMMIT_IDS - 1) % N_COMMIT_IDS; +} + +static unsigned char next_commit_seq(unsigned char seq) +{ + return (seq + 1) % N_COMMIT_IDS; +} + +/* + * In-memory structures + */ + +struct journal_node { + struct rb_node node; + sector_t sector; +}; + +struct alg_spec { + char *alg_string; + char *key_string; + __u8 *key; + unsigned key_size; +}; + +struct dm_integrity_c { + struct dm_dev *dev; + unsigned tag_size; + __s8 log2_tag_size; + sector_t start; + mempool_t *journal_io_mempool; + struct dm_io_client *io; + struct dm_bufio_client *bufio; + struct workqueue_struct *metadata_wq; + struct superblock *sb; + unsigned journal_pages; + struct page_list *journal; + struct page_list *journal_io; + struct page_list *journal_xor; + + struct crypto_skcipher *journal_crypt; + struct scatterlist **journal_scatterlist; + struct scatterlist **journal_io_scatterlist; + struct skcipher_request **sk_requests; + + struct crypto_shash *journal_mac; + + struct journal_node *journal_tree; + struct rb_root journal_tree_root; + + sector_t provided_data_sectors; + + unsigned short journal_entry_size; + unsigned char journal_entries_per_sector; + unsigned char journal_section_entries; + unsigned char journal_section_sectors; + unsigned journal_sections; + unsigned journal_entries; + sector_t device_sectors; + unsigned initial_sectors; + unsigned metadata_run; + __s8 log2_metadata_run; + __u8 log2_buffer_sectors; + + unsigned char mode; + bool suspending; + + int failed; + + struct crypto_shash *internal_hash; + + /* these variables are locked with endio_wait.lock */ + struct rb_root in_progress; + wait_queue_head_t endio_wait; + struct workqueue_struct *wait_wq; + + unsigned char commit_seq; + commit_id_t commit_ids[N_COMMIT_IDS]; + + unsigned committed_section; + unsigned n_committed_sections; + + unsigned uncommitted_section; + unsigned n_uncommitted_sections; + + unsigned free_section; + unsigned char free_section_entry; + unsigned free_sectors; + + unsigned free_sectors_threshold; + + struct workqueue_struct *commit_wq; + struct work_struct commit_work; + + struct workqueue_struct *writer_wq; + struct work_struct writer_work; + + struct bio_list flush_bio_list; + + unsigned long autocommit_jiffies; + struct timer_list autocommit_timer; + unsigned autocommit_msec; + + wait_queue_head_t copy_to_journal_wait; + + struct completion crypto_backoff; + + bool journal_uptodate; + bool just_formatted; + + struct alg_spec internal_hash_alg; + struct alg_spec journal_crypt_alg; + struct alg_spec journal_mac_alg; +}; + +struct dm_integrity_range { + sector_t logical_sector; + unsigned n_sectors; + struct rb_node node; +}; + +struct dm_integrity_io { + struct work_struct work; + + struct dm_integrity_c *ic; + bool write; + bool fua; + + struct dm_integrity_range range; + + sector_t metadata_block; + unsigned metadata_offset; + + atomic_t in_flight; + int bi_error; + + struct completion *completion; + + struct block_device *orig_bi_bdev; + bio_end_io_t *orig_bi_end_io; + struct bio_integrity_payload *orig_bi_integrity; + struct bvec_iter orig_bi_iter; +}; + +struct journal_completion { + struct dm_integrity_c *ic; + atomic_t in_flight; + struct completion comp; +}; + +struct journal_io { + struct dm_integrity_range range; + struct journal_completion *comp; +}; + +static struct kmem_cache *journal_io_cache; + +#define JOURNAL_IO_MEMPOOL 32 + +#ifdef DEBUG_PRINT +#define DEBUG_print(x, ...) printk(KERN_DEBUG x, ##__VA_ARGS__) +static void __DEBUG_bytes(__u8 *bytes, size_t len, const char *msg, ...) +{ + va_list args; + va_start(args, msg); + vprintk(msg, args); + va_end(args); + if (len) + pr_cont(":"); + while (len) { + pr_cont(" %02x", *bytes); + bytes++; + len--; + } + pr_cont("\n"); +} +#define DEBUG_bytes(bytes, len, msg, ...) __DEBUG_bytes(bytes, len, KERN_DEBUG msg, ##__VA_ARGS__) +#else +#define DEBUG_print(x, ...) do { } while (0) +#define DEBUG_bytes(bytes, len, msg, ...) do { } while (0) +#endif + +/* + * DM Integrity profile, protection is performed layer above (dm-crypt) + */ +static struct blk_integrity_profile dm_integrity_profile = { + .name = "DM-DIF-EXT-TAG", + .generate_fn = NULL, + .verify_fn = NULL, +}; + +static void dm_integrity_map_continue(struct dm_integrity_io *dio, bool from_map); +static void integrity_bio_wait(struct work_struct *w); +static void dm_integrity_dtr(struct dm_target *ti); + +static void dm_integrity_io_error(struct dm_integrity_c *ic, const char *msg, int err) +{ + if (!cmpxchg(&ic->failed, 0, err)) + DMERR("Error on %s: %d", msg, err); +} + +static int dm_integrity_failed(struct dm_integrity_c *ic) +{ + return ACCESS_ONCE(ic->failed); +} + +static commit_id_t dm_integrity_commit_id(struct dm_integrity_c *ic, unsigned i, + unsigned j, unsigned char seq) +{ + /* + * Xor the number with section and sector, so that if a piece of + * journal is written at wrong place, it is detected. + */ + return ic->commit_ids[seq] ^ cpu_to_le64(((__u64)i << 32) ^ j); +} + +static void get_area_and_offset(struct dm_integrity_c *ic, sector_t data_sector, + sector_t *area, sector_t *offset) +{ + __u8 log2_interleave_sectors = ic->sb->log2_interleave_sectors; + + *area = data_sector >> log2_interleave_sectors; + *offset = (unsigned)data_sector & ((1U << log2_interleave_sectors) - 1); +} + +static __u64 get_metadata_sector_and_offset(struct dm_integrity_c *ic, sector_t area, + sector_t offset, unsigned *metadata_offset) +{ + __u64 ms; + unsigned mo; + + ms = area << ic->sb->log2_interleave_sectors; + if (likely(ic->log2_metadata_run >= 0)) + ms += area << ic->log2_metadata_run; + else + ms += area * ic->metadata_run; + ms >>= ic->log2_buffer_sectors; + + if (likely(ic->log2_tag_size >= 0)) { + ms += offset >> (SECTOR_SHIFT + ic->log2_buffer_sectors - ic->log2_tag_size); + mo = (offset << ic->log2_tag_size) & ((1U << SECTOR_SHIFT << ic->log2_buffer_sectors) - 1); + } else { + ms += (__u64)offset * ic->tag_size >> (SECTOR_SHIFT + ic->log2_buffer_sectors); + mo = (offset * ic->tag_size) & ((1U << SECTOR_SHIFT << ic->log2_buffer_sectors) - 1); + } + *metadata_offset = mo; + return ms; +} + +static sector_t get_data_sector(struct dm_integrity_c *ic, sector_t area, sector_t offset) +{ + sector_t result; + + result = area << ic->sb->log2_interleave_sectors; + if (likely(ic->log2_metadata_run >= 0)) + result += (area + 1) << ic->log2_metadata_run; + else + result += (area + 1) * ic->metadata_run; + + result += (sector_t)ic->initial_sectors + offset; + return result; +} + +static void wraparound_section(struct dm_integrity_c *ic, unsigned *sec_ptr) +{ + if (unlikely(*sec_ptr >= ic->journal_sections)) + *sec_ptr -= ic->journal_sections; +} + +static int sync_rw_sb(struct dm_integrity_c *ic, int op, int op_flags) +{ + struct dm_io_request io_req; + struct dm_io_region io_loc; + + io_req.bi_op = op; + io_req.bi_op_flags = op_flags; + io_req.mem.type = DM_IO_KMEM; + io_req.mem.ptr.addr = ic->sb; + io_req.notify.fn = NULL; + io_req.client = ic->io; + io_loc.bdev = ic->dev->bdev; + io_loc.sector = ic->start; + io_loc.count = SB_SECTORS; + + return dm_io(&io_req, 1, &io_loc, NULL); +} + +static void access_journal_check(struct dm_integrity_c *ic, unsigned section, unsigned offset, + bool e, const char *function) +{ +#if defined(CONFIG_DM_DEBUG) || defined(INTERNAL_VERIFY) + unsigned limit = e ? ic->journal_section_entries : ic->journal_section_sectors; + + if (unlikely(section >= ic->journal_sections) || + unlikely(offset >= limit)) { + printk(KERN_CRIT "%s: invalid access at (%u,%u), limit (%u,%u)\n", + function, section, offset, ic->journal_sections, limit); + BUG(); + } +#endif +} + +static void page_list_location(struct dm_integrity_c *ic, unsigned section, unsigned offset, + unsigned *pl_index, unsigned *pl_offset) +{ + unsigned sector; + + access_journal_check(ic, section, offset, false, "access_journal"); + + sector = section * ic->journal_section_sectors + offset; + + *pl_index = sector >> (PAGE_SHIFT - SECTOR_SHIFT); + *pl_offset = (sector << SECTOR_SHIFT) & (PAGE_SIZE - 1); +} + +static struct journal_sector *access_page_list(struct dm_integrity_c *ic, struct page_list *pl, + unsigned section, unsigned offset, unsigned *n_sectors) +{ + unsigned pl_index, pl_offset; + char *va; + + page_list_location(ic, section, offset, &pl_index, &pl_offset); + + if (n_sectors) + *n_sectors = (PAGE_SIZE - pl_offset) >> SECTOR_SHIFT; + + va = lowmem_page_address(pl[pl_index].page); + + return (struct journal_sector *)(va + pl_offset); +} + +static struct journal_sector *access_journal(struct dm_integrity_c *ic, unsigned section, unsigned offset) +{ + return access_page_list(ic, ic->journal, section, offset, NULL); +} + +static struct journal_entry *access_journal_entry(struct dm_integrity_c *ic, unsigned section, unsigned n) +{ + unsigned rel_sector, offset; + struct journal_sector *js; + + access_journal_check(ic, section, n, true, "access_journal_entry"); + + rel_sector = n % JOURNAL_BLOCK_SECTORS; + offset = n / JOURNAL_BLOCK_SECTORS; + + js = access_journal(ic, section, rel_sector); + return (struct journal_entry *)((char *)js + offset * ic->journal_entry_size); +} + +static struct journal_sector *access_journal_data(struct dm_integrity_c *ic, unsigned section, unsigned n) +{ + access_journal_check(ic, section, n, true, "access_journal_data"); + + return access_journal(ic, section, n + JOURNAL_BLOCK_SECTORS); +} + +static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result[JOURNAL_MAC_SIZE]) +{ + SHASH_DESC_ON_STACK(desc, ic->journal_mac); + int r; + unsigned j, size; + + desc->tfm = ic->journal_mac; + desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; + + r = crypto_shash_init(desc); + if (unlikely(r)) { + dm_integrity_io_error(ic, "crypto_shash_init", r); + goto err; + } + + for (j = 0; j < ic->journal_section_entries; j++) { + struct journal_entry *je = access_journal_entry(ic, section, j); + r = crypto_shash_update(desc, (__u8 *)&je->u.sector, sizeof je->u.sector); + if (unlikely(r)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto err; + } + } + + size = crypto_shash_digestsize(ic->journal_mac); + + if (likely(size <= JOURNAL_MAC_SIZE)) { + r = crypto_shash_final(desc, result); + if (unlikely(r)) { + dm_integrity_io_error(ic, "crypto_shash_final", r); + goto err; + } + memset(result + size, 0, JOURNAL_MAC_SIZE - size); + } else { + __u8 digest[size]; + r = crypto_shash_final(desc, digest); + if (unlikely(r)) { + dm_integrity_io_error(ic, "crypto_shash_final", r); + goto err; + } + memcpy(result, digest, JOURNAL_MAC_SIZE); + } + + return; +err: + memset(result, 0, JOURNAL_MAC_SIZE); +} + +static void rw_section_mac(struct dm_integrity_c *ic, unsigned section, bool wr) +{ + __u8 result[JOURNAL_MAC_SIZE]; + unsigned j; + + if (!ic->journal_mac) + return; + + section_mac(ic, section, result); + + for (j = 0; j < JOURNAL_BLOCK_SECTORS; j++) { + struct journal_sector *js = access_journal(ic, section, j); + + if (likely(wr)) + memcpy(&js->mac, result + (j * JOURNAL_MAC_PER_SECTOR), JOURNAL_MAC_PER_SECTOR); + else { + if (memcmp(&js->mac, result + (j * JOURNAL_MAC_PER_SECTOR), JOURNAL_MAC_PER_SECTOR)) + dm_integrity_io_error(ic, "journal mac", -EILSEQ); + } + } +} + +static void complete_journal_op(void *context) +{ + struct journal_completion *comp = context; + BUG_ON(!atomic_read(&comp->in_flight)); + if (likely(atomic_dec_and_test(&comp->in_flight))) + complete(&comp->comp); +} + +static void xor_journal(struct dm_integrity_c *ic, bool encrypt, unsigned section, + unsigned n_sections, struct journal_completion *comp) +{ + struct async_submit_ctl submit; + size_t n_bytes = (size_t)(n_sections * ic->journal_section_sectors) << SECTOR_SHIFT; + unsigned pl_index, pl_offset, section_index; + struct page_list *source_pl, *target_pl; + + if (likely(encrypt)) { + source_pl = ic->journal; + target_pl = ic->journal_io; + } else { + source_pl = ic->journal_io; + target_pl = ic->journal; + } + + page_list_location(ic, section, 0, &pl_index, &pl_offset); + + atomic_add(roundup(pl_offset + n_bytes, PAGE_SIZE) >> PAGE_SHIFT, &comp->in_flight); + + init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, complete_journal_op, comp, NULL); + + section_index = pl_index; + + do { + size_t this_step; + struct page *src_pages[2]; + struct page *dst_page; + + while (unlikely(pl_index == section_index)) { + unsigned dummy; + if (likely(encrypt)) + rw_section_mac(ic, section, true); + section++; + n_sections--; + if (!n_sections) + break; + page_list_location(ic, section, 0, §ion_index, &dummy); + } + + this_step = min(n_bytes, (size_t)PAGE_SIZE - pl_offset); + dst_page = target_pl[pl_index].page; + src_pages[0] = source_pl[pl_index].page; + src_pages[1] = ic->journal_xor[pl_index].page; + + async_xor(dst_page, src_pages, pl_offset, 2, this_step, &submit); + + pl_index++; + pl_offset = 0; + n_bytes -= this_step; + } while (n_bytes); + + BUG_ON(n_sections); + + async_tx_issue_pending_all(); +} + +static void complete_journal_encrypt(struct crypto_async_request *req, int err) +{ + struct journal_completion *comp = req->data; + if (unlikely(err)) { + if (likely(err == -EINPROGRESS)) { + complete(&comp->ic->crypto_backoff); + return; + } + dm_integrity_io_error(comp->ic, "asynchronous encrypt", err); + } + complete_journal_op(comp); +} + +static bool do_crypt(bool encrypt, struct skcipher_request *req, struct journal_completion *comp) +{ + int r; + skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, + complete_journal_encrypt, comp); + if (likely(encrypt)) + r = crypto_skcipher_encrypt(req); + else + r = crypto_skcipher_decrypt(req); + if (likely(!r)) + return false; + if (likely(r == -EINPROGRESS)) + return true; + if (likely(r == -EBUSY)) { + wait_for_completion(&comp->ic->crypto_backoff); + reinit_completion(&comp->ic->crypto_backoff); + return true; + } + dm_integrity_io_error(comp->ic, "encrypt", r); + return false; +} + +static void crypt_journal(struct dm_integrity_c *ic, bool encrypt, unsigned section, + unsigned n_sections, struct journal_completion *comp) +{ + struct scatterlist **source_sg; + struct scatterlist **target_sg; + + atomic_add(2, &comp->in_flight); + + if (likely(encrypt)) { + source_sg = ic->journal_scatterlist; + target_sg = ic->journal_io_scatterlist; + } else { + source_sg = ic->journal_io_scatterlist; + target_sg = ic->journal_scatterlist; + } + + do { + struct skcipher_request *req; + unsigned ivsize; + char *iv; + + if (likely(encrypt)) + rw_section_mac(ic, section, true); + + req = ic->sk_requests[section]; + ivsize = crypto_skcipher_ivsize(ic->journal_crypt); + iv = req->iv; + + memcpy(iv, iv + ivsize, ivsize); + + req->src = source_sg[section]; + req->dst = target_sg[section]; + + if (unlikely(do_crypt(encrypt, req, comp))) + atomic_inc(&comp->in_flight); + + section++; + n_sections--; + } while (n_sections); + + atomic_dec(&comp->in_flight); + complete_journal_op(comp); +} + +static void encrypt_journal(struct dm_integrity_c *ic, bool encrypt, unsigned section, + unsigned n_sections, struct journal_completion *comp) +{ + if (ic->journal_xor) + return xor_journal(ic, encrypt, section, n_sections, comp); + else + return crypt_journal(ic, encrypt, section, n_sections, comp); +} + +static void complete_journal_io(unsigned long error, void *context) +{ + struct journal_completion *comp = context; + if (unlikely(error != 0)) + dm_integrity_io_error(comp->ic, "writing journal", -EIO); + complete_journal_op(comp); +} + +static void rw_journal(struct dm_integrity_c *ic, int op, int op_flags, unsigned section, + unsigned n_sections, struct journal_completion *comp) +{ + struct dm_io_request io_req; + struct dm_io_region io_loc; + unsigned sector, n_sectors, pl_index, pl_offset; + int r; + + if (unlikely(dm_integrity_failed(ic))) { + if (comp) + complete_journal_io(-1UL, comp); + return; + } + + sector = section * ic->journal_section_sectors; + n_sectors = n_sections * ic->journal_section_sectors; + + pl_index = sector >> (PAGE_SHIFT - SECTOR_SHIFT); + pl_offset = (sector << SECTOR_SHIFT) & (PAGE_SIZE - 1); + + io_req.bi_op = op; + io_req.bi_op_flags = op_flags; + io_req.mem.type = DM_IO_PAGE_LIST; + if (ic->journal_io) + io_req.mem.ptr.pl = &ic->journal_io[pl_index]; + else + io_req.mem.ptr.pl = &ic->journal[pl_index]; + io_req.mem.offset = pl_offset; + if (likely(comp != NULL)) { + io_req.notify.fn = complete_journal_io; + io_req.notify.context = comp; + } else { + io_req.notify.fn = NULL; + } + io_req.client = ic->io; + io_loc.bdev = ic->dev->bdev; + io_loc.sector = ic->start + SB_SECTORS + sector; + io_loc.count = n_sectors; + + r = dm_io(&io_req, 1, &io_loc, NULL); + if (unlikely(r)) { + dm_integrity_io_error(ic, op == REQ_OP_READ ? "reading journal" : "writing journal", r); + if (comp) { + WARN_ONCE(1, "asynchronous dm_io failed: %d", r); + complete_journal_io(-1UL, comp); + } + } +} + +static void write_journal(struct dm_integrity_c *ic, unsigned commit_start, unsigned commit_sections) +{ + struct journal_completion io_comp; + struct journal_completion crypt_comp_1; + struct journal_completion crypt_comp_2; + unsigned i; + + io_comp.ic = ic; + io_comp.comp = COMPLETION_INITIALIZER_ONSTACK(io_comp.comp); + + if (commit_start + commit_sections <= ic->journal_sections) { + io_comp.in_flight = (atomic_t)ATOMIC_INIT(1); + if (ic->journal_io) { + crypt_comp_1.ic = ic; + crypt_comp_1.comp = COMPLETION_INITIALIZER_ONSTACK(crypt_comp_1.comp); + crypt_comp_1.in_flight = (atomic_t)ATOMIC_INIT(0); + encrypt_journal(ic, true, commit_start, commit_sections, &crypt_comp_1); + wait_for_completion_io(&crypt_comp_1.comp); + } else { + for (i = 0; i < commit_sections; i++) + rw_section_mac(ic, commit_start + i, true); + } + rw_journal(ic, REQ_OP_WRITE, REQ_FUA, commit_start, commit_sections, &io_comp); + } else { + unsigned to_end; + io_comp.in_flight = (atomic_t)ATOMIC_INIT(2); + to_end = ic->journal_sections - commit_start; + if (ic->journal_io) { + crypt_comp_1.ic = ic; + crypt_comp_1.comp = COMPLETION_INITIALIZER_ONSTACK(crypt_comp_1.comp); + crypt_comp_1.in_flight = (atomic_t)ATOMIC_INIT(0); + encrypt_journal(ic, true, commit_start, to_end, &crypt_comp_1); + if (try_wait_for_completion(&crypt_comp_1.comp)) { + rw_journal(ic, REQ_OP_WRITE, REQ_FUA, commit_start, to_end, &io_comp); + crypt_comp_1.comp = COMPLETION_INITIALIZER_ONSTACK(crypt_comp_1.comp); + crypt_comp_1.in_flight = (atomic_t)ATOMIC_INIT(0); + encrypt_journal(ic, true, 0, commit_sections - to_end, &crypt_comp_1); + wait_for_completion_io(&crypt_comp_1.comp); + } else { + crypt_comp_2.ic = ic; + crypt_comp_2.comp = COMPLETION_INITIALIZER_ONSTACK(crypt_comp_2.comp); + crypt_comp_2.in_flight = (atomic_t)ATOMIC_INIT(0); + encrypt_journal(ic, true, 0, commit_sections - to_end, &crypt_comp_2); + wait_for_completion_io(&crypt_comp_1.comp); + rw_journal(ic, REQ_OP_WRITE, REQ_FUA, commit_start, to_end, &io_comp); + wait_for_completion_io(&crypt_comp_2.comp); + } + } else { + for (i = 0; i < to_end; i++) + rw_section_mac(ic, commit_start + i, true); + rw_journal(ic, REQ_OP_WRITE, REQ_FUA, commit_start, to_end, &io_comp); + for (i = 0; i < commit_sections - to_end; i++) + rw_section_mac(ic, i, true); + } + rw_journal(ic, REQ_OP_WRITE, REQ_FUA, 0, commit_sections - to_end, &io_comp); + } + + wait_for_completion_io(&io_comp.comp); +} + +static void copy_from_journal(struct dm_integrity_c *ic, unsigned section, unsigned offset, + unsigned n_sectors, sector_t target, io_notify_fn fn, void *data) +{ + struct dm_io_request io_req; + struct dm_io_region io_loc; + int r; + unsigned sector, pl_index, pl_offset; + + if (unlikely(dm_integrity_failed(ic))) { + fn(-1UL, data); + return; + } + + sector = section * ic->journal_section_sectors + JOURNAL_BLOCK_SECTORS + offset; + + pl_index = sector >> (PAGE_SHIFT - SECTOR_SHIFT); + pl_offset = (sector << SECTOR_SHIFT) & (PAGE_SIZE - 1); + + io_req.bi_op = REQ_OP_WRITE; + io_req.bi_op_flags = 0; + io_req.mem.type = DM_IO_PAGE_LIST; + io_req.mem.ptr.pl = &ic->journal[pl_index]; + io_req.mem.offset = pl_offset; + io_req.notify.fn = fn; + io_req.notify.context = data; + io_req.client = ic->io; + io_loc.bdev = ic->dev->bdev; + io_loc.sector = ic->start + target; + io_loc.count = n_sectors; + + r = dm_io(&io_req, 1, &io_loc, NULL); + if (unlikely(r)) { + WARN_ONCE(1, "asynchronous dm_io failed: %d", r); + fn(-1UL, data); + } +} + +static bool add_new_range(struct dm_integrity_c *ic, struct dm_integrity_range *new_range) +{ + struct rb_node **n = &ic->in_progress.rb_node; + struct rb_node *parent; + + parent = NULL; + + while (*n) { + struct dm_integrity_range *range = container_of(*n, struct dm_integrity_range, node); + + parent = *n; + if (new_range->logical_sector + new_range->n_sectors <= range->logical_sector) { + n = &range->node.rb_left; + } else if (new_range->logical_sector >= range->logical_sector + range->n_sectors) { + n = &range->node.rb_right; + } else { + return false; + } + } + + rb_link_node(&new_range->node, parent, n); + rb_insert_color(&new_range->node, &ic->in_progress); + + return true; +} + +static void remove_range_unlocked(struct dm_integrity_c *ic, struct dm_integrity_range *range) +{ + rb_erase(&range->node, &ic->in_progress); + wake_up_locked(&ic->endio_wait); +} + +static void remove_range(struct dm_integrity_c *ic, struct dm_integrity_range *range) +{ + unsigned long flags; + + spin_lock_irqsave(&ic->endio_wait.lock, flags); + remove_range_unlocked(ic, range); + spin_unlock_irqrestore(&ic->endio_wait.lock, flags); +} + +static void init_journal_node(struct journal_node *node) +{ + RB_CLEAR_NODE(&node->node); + node->sector = (sector_t)-1; +} + +static void add_journal_node(struct dm_integrity_c *ic, struct journal_node *node, sector_t sector) +{ + struct rb_node **link; + struct rb_node *parent; + + node->sector = sector; + BUG_ON(!RB_EMPTY_NODE(&node->node)); + + link = &ic->journal_tree_root.rb_node; + parent = NULL; + + while (*link) { + struct journal_node *j; + parent = *link; + j = container_of(parent, struct journal_node, node); + if (sector < j->sector) + link = &j->node.rb_left; + else + link = &j->node.rb_right; + } + + rb_link_node(&node->node, parent, link); + rb_insert_color(&node->node, &ic->journal_tree_root); +} + +static void remove_journal_node(struct dm_integrity_c *ic, struct journal_node *node) +{ + BUG_ON(RB_EMPTY_NODE(&node->node)); + rb_erase(&node->node, &ic->journal_tree_root); + init_journal_node(node); +} + +#define NOT_FOUND (-1U) + +static unsigned find_journal_node(struct dm_integrity_c *ic, sector_t sector, sector_t *next_sector) +{ + struct rb_node *n = ic->journal_tree_root.rb_node; + unsigned found = NOT_FOUND; + *next_sector = (sector_t)-1; + while (n) { + struct journal_node *j = container_of(n, struct journal_node, node); + if (sector == j->sector) { + found = j - ic->journal_tree; + } + if (sector < j->sector) { + *next_sector = j->sector; + n = j->node.rb_left; + } else { + n = j->node.rb_right; + } + } + + return found; +} + +static bool test_journal_node(struct dm_integrity_c *ic, unsigned pos, sector_t sector) +{ + struct journal_node *node, *next_node; + struct rb_node *next; + + if (unlikely(pos >= ic->journal_entries)) + return false; + node = &ic->journal_tree[pos]; + if (unlikely(RB_EMPTY_NODE(&node->node))) + return false; + if (unlikely(node->sector != sector)) + return false; + + next = rb_next(&node->node); + if (unlikely(!next)) + return true; + + next_node = container_of(next, struct journal_node, node); + return next_node->sector != sector; +} + +static bool find_newer_committed_node(struct dm_integrity_c *ic, struct journal_node *node) +{ + struct rb_node *next; + struct journal_node *next_node; + unsigned next_section; + + BUG_ON(RB_EMPTY_NODE(&node->node)); + + next = rb_next(&node->node); + if (unlikely(!next)) + return false; + + next_node = container_of(next, struct journal_node, node); + + if (next_node->sector != node->sector) + return false; + + next_section = (unsigned)(next_node - ic->journal_tree) / ic->journal_section_entries; + if (next_section >= ic->committed_section && + next_section < ic->committed_section + ic->n_committed_sections) + return true; + if (next_section + ic->journal_sections < ic->committed_section + ic->n_committed_sections) + return true; + + return false; +} + +#define TAG_READ 0 +#define TAG_WRITE 1 +#define TAG_CMP 2 + +static int dm_integrity_rw_tag(struct dm_integrity_c *ic, unsigned char *tag, sector_t *metadata_block, + unsigned *metadata_offset, unsigned total_size, int op) +{ + do { + unsigned char *data, *dp; + struct dm_buffer *b; + unsigned to_copy; + int r; + + r = dm_integrity_failed(ic); + if (unlikely(r)) + return r; + + data = dm_bufio_read(ic->bufio, *metadata_block, &b); + if (unlikely(IS_ERR(data))) + return PTR_ERR(data); + + to_copy = min((1U << SECTOR_SHIFT << ic->log2_buffer_sectors) - *metadata_offset, total_size); + dp = data + *metadata_offset; + if (op == TAG_READ) { + memcpy(tag, dp, to_copy); + } else if (op == TAG_WRITE) { + memcpy(dp, tag, to_copy); + dm_bufio_mark_buffer_dirty(b); + } else { + /* e.g.: op == TAG_CMP */ + if (unlikely(memcmp(dp, tag, to_copy))) { + unsigned i; + + for (i = 0; i < to_copy; i++) { + if (dp[i] != tag[i]) + break; + total_size--; + } + dm_bufio_release(b); + return total_size; + } + } + dm_bufio_release(b); + + tag += to_copy; + *metadata_offset += to_copy; + if (unlikely(*metadata_offset == 1U << SECTOR_SHIFT << ic->log2_buffer_sectors)) { + (*metadata_block)++; + *metadata_offset = 0; + } + total_size -= to_copy; + } while (unlikely(total_size)); + + return 0; +} + +static void dm_integrity_flush_buffers(struct dm_integrity_c *ic) +{ + int r; + r = dm_bufio_write_dirty_buffers(ic->bufio); + if (unlikely(r)) + dm_integrity_io_error(ic, "writing tags", r); +} + +static void sleep_on_endio_wait(struct dm_integrity_c *ic) +{ + DECLARE_WAITQUEUE(wait, current); + __add_wait_queue(&ic->endio_wait, &wait); + __set_current_state(TASK_UNINTERRUPTIBLE); + spin_unlock_irq(&ic->endio_wait.lock); + io_schedule(); + spin_lock_irq(&ic->endio_wait.lock); + __remove_wait_queue(&ic->endio_wait, &wait); +} + +static void autocommit_fn(unsigned long data) +{ + struct dm_integrity_c *ic = (struct dm_integrity_c *)data; + + if (likely(!dm_integrity_failed(ic))) + queue_work(ic->commit_wq, &ic->commit_work); +} + +static void schedule_autocommit(struct dm_integrity_c *ic) +{ + if (!timer_pending(&ic->autocommit_timer)) + mod_timer(&ic->autocommit_timer, jiffies + ic->autocommit_jiffies); +} + +static void submit_flush_bio(struct dm_integrity_c *ic, struct dm_integrity_io *dio) +{ + struct bio *bio; + spin_lock_irq(&ic->endio_wait.lock); + bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); + bio_list_add(&ic->flush_bio_list, bio); + spin_unlock_irq(&ic->endio_wait.lock); + queue_work(ic->commit_wq, &ic->commit_work); +} + +static void do_endio(struct dm_integrity_c *ic, struct bio *bio) +{ + int r = dm_integrity_failed(ic); + if (unlikely(r) && !bio->bi_error) + bio->bi_error = r; + bio_endio(bio); +} + +static void do_endio_flush(struct dm_integrity_c *ic, struct dm_integrity_io *dio) +{ + struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); + + if (unlikely(dio->fua) && likely(!bio->bi_error) && likely(!dm_integrity_failed(ic))) + submit_flush_bio(ic, dio); + else + do_endio(ic, bio); +} + +static void dec_in_flight(struct dm_integrity_io *dio) +{ + if (atomic_dec_and_test(&dio->in_flight)) { + struct dm_integrity_c *ic = dio->ic; + struct bio *bio; + + remove_range(ic, &dio->range); + + if (unlikely(dio->write)) + schedule_autocommit(ic); + + bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); + + if (unlikely(dio->bi_error) && !bio->bi_error) + bio->bi_error = dio->bi_error; + if (likely(!bio->bi_error) && unlikely(bio_sectors(bio) != dio->range.n_sectors)) { + dio->range.logical_sector += dio->range.n_sectors; + bio_advance(bio, dio->range.n_sectors << SECTOR_SHIFT); + INIT_WORK(&dio->work, integrity_bio_wait); + queue_work(ic->wait_wq, &dio->work); + return; + } + do_endio_flush(ic, dio); + } +} + +static void integrity_end_io(struct bio *bio) +{ + struct dm_integrity_io *dio = dm_per_bio_data(bio, sizeof(struct dm_integrity_io)); + + bio->bi_iter = dio->orig_bi_iter; + bio->bi_bdev = dio->orig_bi_bdev; + if (dio->orig_bi_integrity) { + bio->bi_integrity = dio->orig_bi_integrity; + bio->bi_opf |= REQ_INTEGRITY; + } + bio->bi_end_io = dio->orig_bi_end_io; + + if (dio->completion) + complete(dio->completion); + + dec_in_flight(dio); +} + +static void integrity_sector_checksum(struct dm_integrity_c *ic, sector_t sector, + const char *data, char *result) +{ + __u64 sector_le = cpu_to_le64(sector); + SHASH_DESC_ON_STACK(req, ic->internal_hash); + int r; + unsigned digest_size; + + req->tfm = ic->internal_hash; + req->flags = 0; + + r = crypto_shash_init(req); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_init", r); + goto failed; + } + + r = crypto_shash_update(req, (const __u8 *)§or_le, sizeof sector_le); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto failed; + } + + r = crypto_shash_update(req, data, 1 << SECTOR_SHIFT); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto failed; + } + + r = crypto_shash_final(req, result); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_final", r); + goto failed; + } + + digest_size = crypto_shash_digestsize(ic->internal_hash); + if (unlikely(digest_size < ic->tag_size)) + memset(result + digest_size, 0, ic->tag_size - digest_size); + + return; + +failed: + /* this shouldn't happen anyway, the hash functions have no reason to fail */ + get_random_bytes(result, ic->tag_size); +} + +static void integrity_metadata(struct work_struct *w) +{ + struct dm_integrity_io *dio = container_of(w, struct dm_integrity_io, work); + struct dm_integrity_c *ic = dio->ic; + + int r; + + if (ic->internal_hash) { + struct bvec_iter iter; + struct bio_vec bv; + unsigned digest_size = crypto_shash_digestsize(ic->internal_hash); + struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); + char *checksums; + unsigned extra_space = digest_size > ic->tag_size ? digest_size - ic->tag_size : 0; + char checksums_onstack[ic->tag_size + extra_space]; + unsigned sectors_to_process = dio->range.n_sectors; + sector_t sector = dio->range.logical_sector; + + checksums = kmalloc((PAGE_SIZE >> SECTOR_SHIFT) * ic->tag_size + extra_space, + GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN); + if (!checksums) + checksums = checksums_onstack; + + __bio_for_each_segment(bv, bio, iter, dio->orig_bi_iter) { + unsigned pos; + char *mem, *checksums_ptr; + +again: + mem = (char *)kmap_atomic(bv.bv_page) + bv.bv_offset; + pos = 0; + checksums_ptr = checksums; + do { + integrity_sector_checksum(ic, sector, mem + pos, checksums_ptr); + checksums_ptr += ic->tag_size; + sectors_to_process--; + pos += 1 << SECTOR_SHIFT; + sector++; + } while (pos < bv.bv_len && sectors_to_process && checksums != checksums_onstack); + kunmap_atomic(mem); + + r = dm_integrity_rw_tag(ic, checksums, &dio->metadata_block, &dio->metadata_offset, + checksums_ptr - checksums, !dio->write ? TAG_CMP : TAG_WRITE); + if (unlikely(r)) { + if (r > 0) { + DMERR("Checksum failed at sector 0x%llx", + (unsigned long long)(sector - ((r + ic->tag_size - 1) / ic->tag_size))); + r = -EILSEQ; + } + if (likely(checksums != checksums_onstack)) + kfree(checksums); + goto error; + } + + if (!sectors_to_process) + break; + + if (unlikely(pos < bv.bv_len)) { + bv.bv_offset += pos; + bv.bv_len -= pos; + goto again; + } + } + + if (likely(checksums != checksums_onstack)) + kfree(checksums); + } else { + struct bio_integrity_payload *bip = dio->orig_bi_integrity; + + if (bip) { + struct bio_vec biv; + struct bvec_iter iter; + unsigned data_to_process = dio->range.n_sectors * ic->tag_size; + + bip_for_each_vec(biv, bip, iter) { + unsigned char *tag; + unsigned this_len; + + BUG_ON(PageHighMem(biv.bv_page)); + tag = lowmem_page_address(biv.bv_page) + biv.bv_offset; + this_len = min(biv.bv_len, data_to_process); + r = dm_integrity_rw_tag(ic, tag, &dio->metadata_block, &dio->metadata_offset, + this_len, !dio->write ? TAG_READ : TAG_WRITE); + if (unlikely(r)) + goto error; + data_to_process -= this_len; + if (!data_to_process) + break; + } + } + } + dec_in_flight(dio); + return; +error: + dio->bi_error = r; + dec_in_flight(dio); +} + +static int dm_integrity_map(struct dm_target *ti, struct bio *bio) +{ + struct dm_integrity_c *ic = ti->private; + struct dm_integrity_io *dio = dm_per_bio_data(bio, sizeof(struct dm_integrity_io)); + + sector_t area, offset; + + dio->ic = ic; + dio->bi_error = 0; + + if (unlikely(bio->bi_opf & REQ_PREFLUSH)) { + submit_flush_bio(ic, dio); + return DM_MAPIO_SUBMITTED; + } + + dio->range.logical_sector = dm_target_offset(ti, bio->bi_iter.bi_sector); + dio->write = bio_op(bio) == REQ_OP_WRITE; + dio->fua = dio->write && bio->bi_opf & REQ_FUA; + if (unlikely(dio->fua)) { + /* + * Don't pass down the FUA flag because we have to flush + * disk cache anyway. + */ + bio->bi_opf &= ~REQ_FUA; + } + if (unlikely(dio->range.logical_sector + bio_sectors(bio) > ic->provided_data_sectors)) { + DMERR("Too big sector number: 0x%llx + 0x%x > 0x%llx", + (unsigned long long)dio->range.logical_sector, bio_sectors(bio), + (unsigned long long)ic->provided_data_sectors); + return -EIO; + } + + get_area_and_offset(ic, dio->range.logical_sector, &area, &offset); + dio->metadata_block = get_metadata_sector_and_offset(ic, area, offset, &dio->metadata_offset); + bio->bi_iter.bi_sector = get_data_sector(ic, area, offset); + + dm_integrity_map_continue(dio, true); + return DM_MAPIO_SUBMITTED; +} + +static bool __journal_read_write(struct dm_integrity_io *dio, struct bio *bio, + unsigned journal_section, unsigned journal_entry) +{ + struct dm_integrity_c *ic = dio->ic; + sector_t logical_sector; + unsigned n_sectors; + + logical_sector = dio->range.logical_sector; + n_sectors = dio->range.n_sectors; + do { + struct bio_vec bv = bio_iovec(bio); + char *mem; + + if (unlikely(bv.bv_len >> SECTOR_SHIFT > n_sectors)) + bv.bv_len = n_sectors << SECTOR_SHIFT; + n_sectors -= bv.bv_len >> SECTOR_SHIFT; + bio_advance_iter(bio, &bio->bi_iter, bv.bv_len); +retry_kmap: + mem = kmap_atomic(bv.bv_page); + if (likely(dio->write)) + flush_dcache_page(bv.bv_page); + + do { + struct journal_entry *je = access_journal_entry(ic, journal_section, journal_entry); + + if (unlikely(!dio->write)) { + struct journal_sector *js; + + if (unlikely(journal_entry_is_inprogress(je))) { + flush_dcache_page(bv.bv_page); + kunmap_atomic(mem); + + __io_wait_event(ic->copy_to_journal_wait, !journal_entry_is_inprogress(je)); + goto retry_kmap; + } + smp_rmb(); + BUG_ON(journal_entry_get_sector(je) != logical_sector); + js = access_journal_data(ic, journal_section, journal_entry); + memcpy(mem + bv.bv_offset, js, JOURNAL_SECTOR_DATA); + memcpy(mem + bv.bv_offset + JOURNAL_SECTOR_DATA, &je->last_bytes, sizeof je->last_bytes); +#ifdef INTERNAL_VERIFY + if (ic->internal_hash) { + char checksums_onstack[max(crypto_shash_digestsize(ic->internal_hash), ic->tag_size)]; + + integrity_sector_checksum(ic, logical_sector, mem + bv.bv_offset, checksums_onstack); + if (unlikely(memcmp(checksums_onstack, je->tag, ic->tag_size))) { + DMERR("Checksum failed when reading from journal, at sector 0x%llx", + (unsigned long long)logical_sector); + } + } +#endif + } + + if (!ic->internal_hash) { + struct bio_integrity_payload *bip = bio_integrity(bio); + unsigned tag_todo = ic->tag_size; + char *tag_ptr = je->tag; + + if (bip) do { + struct bio_vec biv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter); + unsigned tag_now = min(biv.bv_len, tag_todo); + char *tag_addr; + BUG_ON(PageHighMem(biv.bv_page)); + tag_addr = lowmem_page_address(biv.bv_page) + biv.bv_offset; + if (likely(dio->write)) + memcpy(tag_ptr, tag_addr, tag_now); + else + memcpy(tag_addr, tag_ptr, tag_now); + bvec_iter_advance(bip->bip_vec, &bip->bip_iter, tag_now); + tag_ptr += tag_now; + tag_todo -= tag_now; + } while (unlikely(tag_todo)); else { + if (likely(dio->write)) + memset(tag_ptr, 0, tag_todo); + } + } + + if (likely(dio->write)) { + struct journal_sector *js; + + js = access_journal_data(ic, journal_section, journal_entry); + memcpy(js, mem + bv.bv_offset, 1 << SECTOR_SHIFT); + je->last_bytes = js->commit_id; + + if (ic->internal_hash) { + unsigned digest_size = crypto_shash_digestsize(ic->internal_hash); + if (unlikely(digest_size > ic->tag_size)) { + char checksums_onstack[digest_size]; + integrity_sector_checksum(ic, logical_sector, (char *)js, checksums_onstack); + memcpy(je->tag, checksums_onstack, ic->tag_size); + } else + integrity_sector_checksum(ic, logical_sector, (char *)js, je->tag); + } + + journal_entry_set_sector(je, logical_sector); + } + logical_sector++; + + journal_entry++; + if (unlikely(journal_entry == ic->journal_section_entries)) { + journal_entry = 0; + journal_section++; + wraparound_section(ic, &journal_section); + } + + bv.bv_offset += 1 << SECTOR_SHIFT; + } while (bv.bv_len -= 1 << SECTOR_SHIFT); + + if (unlikely(!dio->write)) + flush_dcache_page(bv.bv_page); + kunmap_atomic(mem); + } while (n_sectors); + + if (likely(dio->write)) { + smp_mb(); + if (unlikely(waitqueue_active(&ic->copy_to_journal_wait))) + wake_up(&ic->copy_to_journal_wait); + if (ACCESS_ONCE(ic->free_sectors) <= ic->free_sectors_threshold) { + queue_work(ic->commit_wq, &ic->commit_work); + } else { + schedule_autocommit(ic); + } + } else { + remove_range(ic, &dio->range); + } + + if (unlikely(bio->bi_iter.bi_size)) { + sector_t area, offset; + + dio->range.logical_sector = logical_sector; + get_area_and_offset(ic, dio->range.logical_sector, &area, &offset); + dio->metadata_block = get_metadata_sector_and_offset(ic, area, offset, &dio->metadata_offset); + return true; + } + + return false; +} + +static void dm_integrity_map_continue(struct dm_integrity_io *dio, bool from_map) +{ + struct dm_integrity_c *ic = dio->ic; + struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); + unsigned journal_section, journal_entry; + unsigned journal_read_pos; + struct completion read_comp; + bool need_sync_io = ic->internal_hash && !dio->write; + + if (need_sync_io && from_map) { + INIT_WORK(&dio->work, integrity_bio_wait); + queue_work(ic->metadata_wq, &dio->work); + return; + } + +lock_retry: + spin_lock_irq(&ic->endio_wait.lock); +retry: + if (unlikely(dm_integrity_failed(ic))) { + spin_unlock_irq(&ic->endio_wait.lock); + do_endio(ic, bio); + return; + } + dio->range.n_sectors = bio_sectors(bio); + journal_read_pos = NOT_FOUND; + if (likely(ic->mode == 'J')) { + if (dio->write) { + unsigned next_entry, i, pos; + unsigned ws, we; + + dio->range.n_sectors = min(dio->range.n_sectors, ic->free_sectors); + if (unlikely(!dio->range.n_sectors)) + goto sleep; + ic->free_sectors -= dio->range.n_sectors; + journal_section = ic->free_section; + journal_entry = ic->free_section_entry; + + next_entry = ic->free_section_entry + dio->range.n_sectors; + ic->free_section_entry = next_entry % ic->journal_section_entries; + ic->free_section += next_entry / ic->journal_section_entries; + ic->n_uncommitted_sections += next_entry / ic->journal_section_entries; + wraparound_section(ic, &ic->free_section); + + pos = journal_section * ic->journal_section_entries + journal_entry; + ws = journal_section; + we = journal_entry; + for (i = 0; i < dio->range.n_sectors; i++) { + struct journal_entry *je; + + add_journal_node(ic, &ic->journal_tree[pos], dio->range.logical_sector + i); + pos++; + if (unlikely(pos >= ic->journal_entries)) + pos = 0; + + je = access_journal_entry(ic, ws, we); + BUG_ON(!journal_entry_is_unused(je)); + journal_entry_set_inprogress(je); + we++; + if (unlikely(we == ic->journal_section_entries)) { + we = 0; + ws++; + wraparound_section(ic, &ws); + } + } + + spin_unlock_irq(&ic->endio_wait.lock); + goto journal_read_write; + } else { + sector_t next_sector; + journal_read_pos = find_journal_node(ic, dio->range.logical_sector, &next_sector); + if (likely(journal_read_pos == NOT_FOUND)) { + if (unlikely(dio->range.n_sectors > next_sector - dio->range.logical_sector)) + dio->range.n_sectors = next_sector - dio->range.logical_sector; + } else { + unsigned i; + for (i = 1; i < dio->range.n_sectors; i++) { + if (!test_journal_node(ic, journal_read_pos + i, dio->range.logical_sector + i)) + break; + } + dio->range.n_sectors = i; + } + } + } + if (unlikely(!add_new_range(ic, &dio->range))) { + /* + * We must not sleep in the request routine because it could + * stall bios on current->bio_list. + * So, we offload the bio to a workqueue if we have to sleep. + */ +sleep: + if (from_map) { + spin_unlock_irq(&ic->endio_wait.lock); + INIT_WORK(&dio->work, integrity_bio_wait); + queue_work(ic->wait_wq, &dio->work); + return; + } else { + sleep_on_endio_wait(ic); + goto retry; + } + } + spin_unlock_irq(&ic->endio_wait.lock); + + if (unlikely(journal_read_pos != NOT_FOUND)) { + journal_section = journal_read_pos / ic->journal_section_entries; + journal_entry = journal_read_pos % ic->journal_section_entries; + goto journal_read_write; + } + + dio->in_flight = (atomic_t)ATOMIC_INIT(2); + + if (need_sync_io) { + read_comp = COMPLETION_INITIALIZER_ONSTACK(read_comp); + dio->completion = &read_comp; + } else + dio->completion = NULL; + + dio->orig_bi_iter = bio->bi_iter; + + dio->orig_bi_bdev = bio->bi_bdev; + bio->bi_bdev = ic->dev->bdev; + + dio->orig_bi_integrity = bio_integrity(bio); + bio->bi_integrity = NULL; + bio->bi_opf &= ~REQ_INTEGRITY; + + dio->orig_bi_end_io = bio->bi_end_io; + bio->bi_end_io = integrity_end_io; + + bio->bi_iter.bi_size = dio->range.n_sectors << SECTOR_SHIFT; + bio->bi_iter.bi_sector += ic->start; + generic_make_request(bio); + + if (need_sync_io) { + wait_for_completion_io(&read_comp); + integrity_metadata(&dio->work); + } else { + INIT_WORK(&dio->work, integrity_metadata); + queue_work(ic->metadata_wq, &dio->work); + } + + return; + +journal_read_write: + if (unlikely(__journal_read_write(dio, bio, journal_section, journal_entry))) + goto lock_retry; + + do_endio_flush(ic, dio); +} + + +static void integrity_bio_wait(struct work_struct *w) +{ + struct dm_integrity_io *dio = container_of(w, struct dm_integrity_io, work); + + dm_integrity_map_continue(dio, false); +} + +static void pad_uncommitted(struct dm_integrity_c *ic) +{ + if (ic->free_section_entry) { + ic->free_sectors -= ic->journal_section_entries - ic->free_section_entry; + ic->free_section_entry = 0; + ic->free_section++; + wraparound_section(ic, &ic->free_section); + ic->n_uncommitted_sections++; + } +} + +static void integrity_commit(struct work_struct *w) +{ + struct dm_integrity_c *ic = container_of(w, struct dm_integrity_c, commit_work); + unsigned commit_start, commit_sections; + unsigned i, j, n; + struct bio *flushes; + + del_timer(&ic->autocommit_timer); + + spin_lock_irq(&ic->endio_wait.lock); + flushes = bio_list_get(&ic->flush_bio_list); + if (unlikely(ic->mode != 'J')) { + spin_unlock_irq(&ic->endio_wait.lock); + dm_integrity_flush_buffers(ic); + goto release_flush_bios; + } + + pad_uncommitted(ic); + commit_start = ic->uncommitted_section; + commit_sections = ic->n_uncommitted_sections; + spin_unlock_irq(&ic->endio_wait.lock); + + if (!commit_sections) + goto release_flush_bios; + + i = commit_start; + for (n = 0; n < commit_sections; n++) { + for (j = 0; j < ic->journal_section_entries; j++) { + struct journal_entry *je; + je = access_journal_entry(ic, i, j); + io_wait_event(ic->copy_to_journal_wait, !journal_entry_is_inprogress(je)); + } + for (j = 0; j < ic->journal_section_sectors; j++) { + struct journal_sector *js; + js = access_journal(ic, i, j); + js->commit_id = dm_integrity_commit_id(ic, i, j, ic->commit_seq); + } + i++; + if (unlikely(i >= ic->journal_sections)) + ic->commit_seq = next_commit_seq(ic->commit_seq); + wraparound_section(ic, &i); + } + smp_rmb(); + + write_journal(ic, commit_start, commit_sections); + + spin_lock_irq(&ic->endio_wait.lock); + ic->uncommitted_section += commit_sections; + wraparound_section(ic, &ic->uncommitted_section); + ic->n_uncommitted_sections -= commit_sections; + ic->n_committed_sections += commit_sections; + spin_unlock_irq(&ic->endio_wait.lock); + + if (ACCESS_ONCE(ic->free_sectors) <= ic->free_sectors_threshold) + queue_work(ic->writer_wq, &ic->writer_work); + +release_flush_bios: + while (flushes) { + struct bio *next = flushes->bi_next; + flushes->bi_next = NULL; + do_endio(ic, flushes); + flushes = next; + } +} + +static void complete_copy_from_journal(unsigned long error, void *context) +{ + struct journal_io *io = context; + struct journal_completion *comp = io->comp; + struct dm_integrity_c *ic = comp->ic; + remove_range(ic, &io->range); + mempool_free(io, ic->journal_io_mempool); + if (unlikely(error != 0)) + dm_integrity_io_error(ic, "copying from journal", -EIO); + complete_journal_op(comp); +} + +static void do_journal_write(struct dm_integrity_c *ic, unsigned write_start, + unsigned write_sections, bool from_replay) +{ + unsigned i, j, n; + struct journal_completion comp; + + comp.ic = ic; + comp.in_flight = (atomic_t)ATOMIC_INIT(1); + comp.comp = COMPLETION_INITIALIZER_ONSTACK(comp.comp); + + i = write_start; + for (n = 0; n < write_sections; n++, i++, wraparound_section(ic, &i)) { +#ifndef INTERNAL_VERIFY + if (unlikely(from_replay)) +#endif + rw_section_mac(ic, i, false); + for (j = 0; j < ic->journal_section_entries; j++) { + struct journal_entry *je = access_journal_entry(ic, i, j); + sector_t sec, area, offset; + unsigned k, l, next_loop; + sector_t metadata_block; + unsigned metadata_offset; + struct journal_io *io; + + if (journal_entry_is_unused(je)) + continue; + BUG_ON(unlikely(journal_entry_is_inprogress(je)) && !from_replay); + sec = journal_entry_get_sector(je); + get_area_and_offset(ic, sec, &area, &offset); + access_journal_data(ic, i, j)->commit_id = je->last_bytes; + for (k = j + 1; k < ic->journal_section_entries; k++) { + struct journal_entry *je2 = access_journal_entry(ic, i, k); + sector_t sec2, area2, offset2; + if (journal_entry_is_unused(je2)) + break; + BUG_ON(unlikely(journal_entry_is_inprogress(je2)) && !from_replay); + sec2 = journal_entry_get_sector(je2); + get_area_and_offset(ic, sec2, &area2, &offset2); + if (area2 != area || offset2 != offset + (k - j)) + break; + access_journal_data(ic, i, k)->commit_id = je2->last_bytes; + } + next_loop = k - 1; + + io = mempool_alloc(ic->journal_io_mempool, GFP_NOIO); + io->comp = ∁ + io->range.logical_sector = sec; + io->range.n_sectors = k - j; + + spin_lock_irq(&ic->endio_wait.lock); + while (unlikely(!add_new_range(ic, &io->range))) + sleep_on_endio_wait(ic); + + if (likely(!from_replay)) { + struct journal_node *section_node = &ic->journal_tree[i * ic->journal_section_entries]; + + /* don't write if there is newer committed sector */ + while (j < k && find_newer_committed_node(ic, §ion_node[j])) { + struct journal_entry *je2 = access_journal_entry(ic, i, j); + + journal_entry_set_unused(je2); + remove_journal_node(ic, §ion_node[j]); + j++; + sec++; + offset++; + } + while (j < k && find_newer_committed_node(ic, §ion_node[k - 1])) { + struct journal_entry *je2 = access_journal_entry(ic, i, k - 1); + + journal_entry_set_unused(je2); + remove_journal_node(ic, §ion_node[k - 1]); + k--; + } + if (j == k) { + remove_range_unlocked(ic, &io->range); + spin_unlock_irq(&ic->endio_wait.lock); + mempool_free(io, ic->journal_io_mempool); + goto skip_io; + } + for (l = j; l < k; l++) { + remove_journal_node(ic, §ion_node[l]); + } + } + spin_unlock_irq(&ic->endio_wait.lock); + + metadata_block = get_metadata_sector_and_offset(ic, area, offset, &metadata_offset); + for (l = j; l < k; l++) { + int r; + struct journal_entry *je2 = access_journal_entry(ic, i, l); + + if ( +#ifndef INTERNAL_VERIFY + unlikely(from_replay) && +#endif + ic->internal_hash) { + unsigned char test_tag[ic->tag_size]; + + integrity_sector_checksum(ic, sec + (l - j), + (char *)access_journal_data(ic, i, l), test_tag); + if (unlikely(memcmp(test_tag, je2->tag, ic->tag_size))) + dm_integrity_io_error(ic, "tag mismatch when replaying journal", -EILSEQ); + } + + journal_entry_set_unused(je2); + r = dm_integrity_rw_tag(ic, je2->tag, &metadata_block, &metadata_offset, + ic->tag_size, TAG_WRITE); + if (unlikely(r)) { + dm_integrity_io_error(ic, "reading tags", r); + } + } + + atomic_inc(&comp.in_flight); + copy_from_journal(ic, i, j, k - j, get_data_sector(ic, area, offset), + complete_copy_from_journal, io); +skip_io: + j = next_loop; + } + } + + dm_bufio_write_dirty_buffers_async(ic->bufio); + + complete_journal_op(&comp); + wait_for_completion_io(&comp.comp); + + dm_integrity_flush_buffers(ic); +} + +static void integrity_writer(struct work_struct *w) +{ + struct dm_integrity_c *ic = container_of(w, struct dm_integrity_c, writer_work); + unsigned write_start, write_sections; + + unsigned prev_free_sectors; + + /* the following test is not needed, but it tests the replay code */ + if (ACCESS_ONCE(ic->suspending)) + return; + + spin_lock_irq(&ic->endio_wait.lock); + write_start = ic->committed_section; + write_sections = ic->n_committed_sections; + spin_unlock_irq(&ic->endio_wait.lock); + + if (!write_sections) + return; + + do_journal_write(ic, write_start, write_sections, false); + + spin_lock_irq(&ic->endio_wait.lock); + + ic->committed_section += write_sections; + wraparound_section(ic, &ic->committed_section); + ic->n_committed_sections -= write_sections; + + prev_free_sectors = ic->free_sectors; + ic->free_sectors += write_sections * ic->journal_section_entries; + if (unlikely(!prev_free_sectors)) + wake_up_locked(&ic->endio_wait); + + spin_unlock_irq(&ic->endio_wait.lock); +} + +static void init_journal(struct dm_integrity_c *ic, unsigned start_section, + unsigned n_sections, unsigned char commit_seq) +{ + unsigned i, j, n; + + if (!n_sections) + return; + + for (n = 0; n < n_sections; n++) { + i = start_section + n; + wraparound_section(ic, &i); + for (j = 0; j < ic->journal_section_sectors; j++) { + struct journal_sector *js = access_journal(ic, i, j); + memset(&js->entries, 0, JOURNAL_SECTOR_DATA); + js->commit_id = dm_integrity_commit_id(ic, i, j, commit_seq); + } + for (j = 0; j < ic->journal_section_entries; j++) { + struct journal_entry *je = access_journal_entry(ic, i, j); + journal_entry_set_unused(je); + } + } + + write_journal(ic, start_section, n_sections); +} + +static int find_commit_seq(struct dm_integrity_c *ic, unsigned i, unsigned j, commit_id_t id) +{ + unsigned char k; + for (k = 0; k < N_COMMIT_IDS; k++) { + if (dm_integrity_commit_id(ic, i, j, k) == id) + return k; + } + dm_integrity_io_error(ic, "journal commit id", -EIO); + return -EIO; +} + +static void replay_journal(struct dm_integrity_c *ic) +{ + unsigned i, j; + bool used_commit_ids[N_COMMIT_IDS]; + unsigned max_commit_id_sections[N_COMMIT_IDS]; + unsigned write_start, write_sections; + unsigned continue_section; + bool journal_empty; + unsigned char unused, last_used, want_commit_seq; + + if (ic->journal_uptodate) + return; + + last_used = 0; + write_start = 0; + + if (!ic->just_formatted) { + DEBUG_print("reading journal\n"); + rw_journal(ic, REQ_OP_READ, 0, 0, ic->journal_sections, NULL); + if (ic->journal_io) + DEBUG_bytes(lowmem_page_address(ic->journal_io[0].page), 64, "read journal"); + if (ic->journal_io) { + struct journal_completion crypt_comp; + crypt_comp.ic = ic; + crypt_comp.comp = COMPLETION_INITIALIZER_ONSTACK(crypt_comp.comp); + crypt_comp.in_flight = (atomic_t)ATOMIC_INIT(0); + encrypt_journal(ic, false, 0, ic->journal_sections, &crypt_comp); + wait_for_completion(&crypt_comp.comp); + } + DEBUG_bytes(lowmem_page_address(ic->journal[0].page), 64, "decrypted journal"); + } + + if (dm_integrity_failed(ic)) + goto clear_journal; + + journal_empty = true; + memset(used_commit_ids, 0, sizeof used_commit_ids); + memset(max_commit_id_sections, 0, sizeof max_commit_id_sections); + for (i = 0; i < ic->journal_sections; i++) { + for (j = 0; j < ic->journal_section_sectors; j++) { + int k; + struct journal_sector *js = access_journal(ic, i, j); + k = find_commit_seq(ic, i, j, js->commit_id); + if (k < 0) + goto clear_journal; + used_commit_ids[k] = true; + max_commit_id_sections[k] = i; + } + if (journal_empty) { + for (j = 0; j < ic->journal_section_entries; j++) { + struct journal_entry *je = access_journal_entry(ic, i, j); + if (!journal_entry_is_unused(je)) { + journal_empty = false; + break; + } + } + } + } + + if (!used_commit_ids[N_COMMIT_IDS - 1]) { + unused = N_COMMIT_IDS - 1; + while (unused && !used_commit_ids[unused - 1]) + unused--; + } else { + for (unused = 0; unused < N_COMMIT_IDS; unused++) + if (!used_commit_ids[unused]) + break; + if (unused == N_COMMIT_IDS) { + dm_integrity_io_error(ic, "journal commit ids", -EIO); + goto clear_journal; + } + } + DEBUG_print("first unused commit seq %d [%d,%d,%d,%d]\n", + unused, used_commit_ids[0], used_commit_ids[1], + used_commit_ids[2], used_commit_ids[3]); + + last_used = prev_commit_seq(unused); + want_commit_seq = prev_commit_seq(last_used); + + if (!used_commit_ids[want_commit_seq] && used_commit_ids[prev_commit_seq(want_commit_seq)]) + journal_empty = true; + + write_start = max_commit_id_sections[last_used] + 1; + if (unlikely(write_start >= ic->journal_sections)) + want_commit_seq = next_commit_seq(want_commit_seq); + wraparound_section(ic, &write_start); + + i = write_start; + for (write_sections = 0; write_sections < ic->journal_sections; write_sections++) { + for (j = 0; j < ic->journal_section_sectors; j++) { + struct journal_sector *js = access_journal(ic, i, j); + + if (js->commit_id != dm_integrity_commit_id(ic, i, j, want_commit_seq)) { + /* + * This could be caused by crash during writing. + * We won't replay the inconsistent part of the + * journal. + */ + DEBUG_print("commit id mismatch at position (%u, %u): %d != %d\n", + i, j, find_commit_seq(ic, i, j, js->commit_id), want_commit_seq); + goto brk; + } + } + i++; + if (unlikely(i >= ic->journal_sections)) + want_commit_seq = next_commit_seq(want_commit_seq); + wraparound_section(ic, &i); + } +brk: + + if (!journal_empty) { + DEBUG_print("replaying %u sections, starting at %u, commit seq %d\n", + write_sections, write_start, want_commit_seq); + do_journal_write(ic, write_start, write_sections, true); + } + + if (write_sections == ic->journal_sections && (ic->mode == 'J' || journal_empty)) { + continue_section = write_start; + ic->commit_seq = want_commit_seq; + DEBUG_print("continuing from section %u, commit seq %d\n", write_start, ic->commit_seq); + } else { + unsigned s; + unsigned char erase_seq; +clear_journal: + DEBUG_print("clearing journal\n"); + + erase_seq = prev_commit_seq(prev_commit_seq(last_used)); + s = write_start; + init_journal(ic, s, 1, erase_seq); + s++; + wraparound_section(ic, &s); + if (ic->journal_sections >= 2) { + init_journal(ic, s, ic->journal_sections - 2, erase_seq); + s += ic->journal_sections - 2; + wraparound_section(ic, &s); + init_journal(ic, s, 1, erase_seq); + } + + continue_section = 0; + ic->commit_seq = next_commit_seq(erase_seq); + } + + ic->committed_section = continue_section; + ic->n_committed_sections = 0; + + ic->uncommitted_section = continue_section; + ic->n_uncommitted_sections = 0; + + ic->free_section = continue_section; + ic->free_section_entry = 0; + ic->free_sectors = ic->journal_entries; + + ic->journal_tree_root = RB_ROOT; + for (i = 0; i < ic->journal_entries; i++) + init_journal_node(&ic->journal_tree[i]); +} + +static void dm_integrity_postsuspend(struct dm_target *ti) +{ + struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private; + + del_timer_sync(&ic->autocommit_timer); + + ic->suspending = true; + + queue_work(ic->commit_wq, &ic->commit_work); + drain_workqueue(ic->commit_wq); + + if (ic->mode == 'J') { + drain_workqueue(ic->writer_wq); + dm_integrity_flush_buffers(ic); + } + + ic->suspending = false; + + BUG_ON(!RB_EMPTY_ROOT(&ic->in_progress)); + + ic->journal_uptodate = true; +} + +static void dm_integrity_resume(struct dm_target *ti) +{ + struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private; + + replay_journal(ic); +} + +static void dm_integrity_status(struct dm_target *ti, status_type_t type, + unsigned status_flags, char *result, unsigned maxlen) +{ + struct dm_integrity_c *ic = (struct dm_integrity_c *)ti->private; + unsigned arg_count; + size_t sz = 0; + + switch (type) { + case STATUSTYPE_INFO: + result[0] = '\0'; + break; + + case STATUSTYPE_TABLE: { + __u64 watermark_percentage = (__u64)(ic->journal_entries - ic->free_sectors_threshold) * 100; + watermark_percentage += ic->journal_entries / 2; + do_div(watermark_percentage, ic->journal_entries); + arg_count = 5; + arg_count += !!ic->internal_hash_alg.alg_string; + arg_count += !!ic->journal_crypt_alg.alg_string; + arg_count += !!ic->journal_mac_alg.alg_string; + DMEMIT("%s %llu %u %c %u", ic->dev->name, (unsigned long long)ic->start, + ic->tag_size, ic->mode, arg_count); + DMEMIT(" journal-sectors:%u", ic->initial_sectors - SB_SECTORS); + DMEMIT(" interleave-sectors:%u", 1U << ic->sb->log2_interleave_sectors); + DMEMIT(" buffer-sectors:%u", 1U << ic->log2_buffer_sectors); + DMEMIT(" journal-watermark:%u", (unsigned)watermark_percentage); + DMEMIT(" commit-time:%u", ic->autocommit_msec); + +#define EMIT_ALG(a, n) \ + do { \ + if (ic->a.alg_string) { \ + DMEMIT(" %s:%s", n, ic->a.alg_string); \ + if (ic->a.key_string) \ + DMEMIT(":%s", ic->a.key_string);\ + } \ + } while (0) + EMIT_ALG(internal_hash_alg, "internal-hash"); + EMIT_ALG(journal_crypt_alg, "journal-crypt"); + EMIT_ALG(journal_mac_alg, "journal-mac"); + break; + } + } +} + +static int dm_integrity_iterate_devices(struct dm_target *ti, + iterate_devices_callout_fn fn, void *data) +{ + struct dm_integrity_c *ic = ti->private; + + return fn(ti, ic->dev, ic->start + ic->initial_sectors + ic->metadata_run, ti->len, data); +} + +static void calculate_journal_section_size(struct dm_integrity_c *ic) +{ + unsigned sector_space = JOURNAL_SECTOR_DATA; + + ic->journal_sections = le32_to_cpu(ic->sb->journal_sections); + ic->journal_entry_size = roundup(offsetof(struct journal_entry, tag) + ic->tag_size, + JOURNAL_ENTRY_ROUNDUP); + + if (ic->sb->flags & cpu_to_le32(SB_FLAG_HAVE_JOURNAL_MAC)) + sector_space -= JOURNAL_MAC_PER_SECTOR; + ic->journal_entries_per_sector = sector_space / ic->journal_entry_size; + ic->journal_section_entries = ic->journal_entries_per_sector * JOURNAL_BLOCK_SECTORS; + ic->journal_section_sectors = ic->journal_section_entries + JOURNAL_BLOCK_SECTORS; + ic->journal_entries = ic->journal_section_entries * ic->journal_sections; +} + +static int calculate_device_limits(struct dm_integrity_c *ic) +{ + __u64 initial_sectors; + sector_t last_sector, last_area, last_offset; + + calculate_journal_section_size(ic); + initial_sectors = SB_SECTORS + (__u64)ic->journal_section_sectors * ic->journal_sections; + if (initial_sectors + METADATA_PADDING_SECTORS >= ic->device_sectors || initial_sectors > UINT_MAX) + return -EINVAL; + ic->initial_sectors = initial_sectors; + + ic->metadata_run = roundup((__u64)ic->tag_size << ic->sb->log2_interleave_sectors, + (__u64)(1 << SECTOR_SHIFT << METADATA_PADDING_SECTORS)) >> SECTOR_SHIFT; + if (!(ic->metadata_run & (ic->metadata_run - 1))) + ic->log2_metadata_run = __ffs(ic->metadata_run); + else + ic->log2_metadata_run = -1; + + get_area_and_offset(ic, ic->provided_data_sectors - 1, &last_area, &last_offset); + last_sector = get_data_sector(ic, last_area, last_offset); + + if (ic->start + last_sector < last_sector || ic->start + last_sector >= ic->device_sectors) + return -EINVAL; + + return 0; +} + +static int initialize_superblock(struct dm_integrity_c *ic, unsigned journal_sectors, unsigned interleave_sectors) +{ + unsigned journal_sections; + int test_bit; + + memcpy(ic->sb->magic, SB_MAGIC, 8); + ic->sb->version = SB_VERSION; + ic->sb->integrity_tag_size = cpu_to_le16(ic->tag_size); + if (ic->journal_mac_alg.alg_string) + ic->sb->flags |= cpu_to_le32(SB_FLAG_HAVE_JOURNAL_MAC); + + calculate_journal_section_size(ic); + journal_sections = journal_sectors / ic->journal_section_sectors; + if (!journal_sections) + journal_sections = 1; + ic->sb->journal_sections = cpu_to_le32(journal_sections); + + ic->sb->log2_interleave_sectors = __fls(interleave_sectors); + ic->sb->log2_interleave_sectors = max((__u8)MIN_INTERLEAVE_SECTORS, ic->sb->log2_interleave_sectors); + ic->sb->log2_interleave_sectors = min((__u8)MAX_INTERLEAVE_SECTORS, ic->sb->log2_interleave_sectors); + + ic->provided_data_sectors = 0; + for (test_bit = fls64(ic->device_sectors) - 1; test_bit >= 3; test_bit--) { + __u64 prev_data_sectors = ic->provided_data_sectors; + + ic->provided_data_sectors |= (sector_t)1 << test_bit; + if (calculate_device_limits(ic)) + ic->provided_data_sectors = prev_data_sectors; + } + + if (!le64_to_cpu(ic->provided_data_sectors)) + return -EINVAL; + + ic->sb->provided_data_sectors = cpu_to_le64(ic->provided_data_sectors); + + return 0; +} + +static void dm_integrity_set(struct dm_target *ti, struct dm_integrity_c *ic) +{ + struct gendisk *disk = dm_disk(dm_table_get_md(ti->table)); + struct blk_integrity bi; + + memset(&bi, 0, sizeof(bi)); + bi.profile = &dm_integrity_profile; + bi.tuple_size = ic->tag_size * (queue_logical_block_size(disk->queue) >> SECTOR_SHIFT); + bi.tag_size = ic->tag_size; + + blk_integrity_register(disk, &bi); + blk_queue_max_integrity_segments(disk->queue, UINT_MAX); +} + +/* FIXME: use new kvmalloc */ +static void *dm_integrity_kvmalloc(size_t size, gfp_t gfp) +{ + void *ptr = NULL; + + if (size <= PAGE_SIZE) + ptr = kmalloc(size, GFP_KERNEL | gfp); + if (!ptr && size <= KMALLOC_MAX_SIZE) + ptr = kmalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY | gfp); + if (!ptr) + ptr = __vmalloc(size, GFP_KERNEL | gfp, PAGE_KERNEL); + + return ptr; +} + +static void dm_integrity_free_page_list(struct dm_integrity_c *ic, struct page_list *pl) +{ + unsigned i; + + if (!pl) + return; + for (i = 0; i < ic->journal_pages; i++) + if (pl[i].page) + __free_page(pl[i].page); + kvfree(pl); +} + +static struct page_list *dm_integrity_alloc_page_list(struct dm_integrity_c *ic) +{ + size_t page_list_desc_size = ic->journal_pages * sizeof(struct page_list); + struct page_list *pl; + unsigned i; + + pl = dm_integrity_kvmalloc(page_list_desc_size, __GFP_ZERO); + if (!pl) + return NULL; + + for (i = 0; i < ic->journal_pages; i++) { + pl[i].page = alloc_page(GFP_KERNEL); + if (!pl[i].page) { + dm_integrity_free_page_list(ic, pl); + return NULL; + } + if (i) + pl[i - 1].next = &pl[i]; + } + + return pl; +} + +static void dm_integrity_free_journal_scatterlist(struct dm_integrity_c *ic, struct scatterlist **sl) +{ + unsigned i; + for (i = 0; i < ic->journal_sections; i++) + kvfree(sl[i]); + kfree(sl); +} + +static struct scatterlist **dm_integrity_alloc_journal_scatterlist(struct dm_integrity_c *ic, struct page_list *pl) +{ + struct scatterlist **sl; + unsigned i; + + sl = dm_integrity_kvmalloc(ic->journal_sections * sizeof(struct scatterlist *), __GFP_ZERO); + if (!sl) + return NULL; + + for (i = 0; i < ic->journal_sections; i++) { + struct scatterlist *s; + unsigned start_index, start_offset; + unsigned end_index, end_offset; + unsigned n_pages; + unsigned idx; + + page_list_location(ic, i, 0, &start_index, &start_offset); + page_list_location(ic, i, ic->journal_section_sectors - 1, &end_index, &end_offset); + + n_pages = (end_index - start_index + 1); + + s = dm_integrity_kvmalloc(n_pages * sizeof(struct scatterlist), 0); + if (!s) { + dm_integrity_free_journal_scatterlist(ic, sl); + return NULL; + } + + sg_init_table(s, n_pages); + for (idx = start_index; idx <= end_index; idx++) { + char *va = lowmem_page_address(pl[idx].page); + unsigned start = 0, end = PAGE_SIZE; + if (idx == start_index) + start = start_offset; + if (idx == end_index) + end = end_offset + (1 << SECTOR_SHIFT); + sg_set_buf(&s[idx - start_index], va + start, end - start); + } + + sl[i] = s; + } + + return sl; +} + +static void free_alg(struct alg_spec *a) +{ + kzfree(a->alg_string); + kzfree(a->key); + memset(a, 0, sizeof *a); +} + +static int get_alg_and_key(const char *arg, struct alg_spec *a, char **error, char *error_inval) +{ + char *k; + + free_alg(a); + + a->alg_string = kstrdup(strchr(arg, ':') + 1, GFP_KERNEL); + if (!a->alg_string) + goto nomem; + + k = strchr(a->alg_string, ':'); + if (k) { + unsigned i; + + *k = 0; + a->key_string = k + 1; + if (strlen(a->key_string) & 1) + goto inval; + + a->key_size = strlen(a->key_string) / 2; + a->key = kmalloc(a->key_size, GFP_KERNEL); + if (!a->key) + goto nomem; + for (i = 0; i < a->key_size; i++) { + char digit[3]; + digit[0] = a->key_string[i * 2]; + digit[1] = a->key_string[i * 2 + 1]; + digit[2] = 0; + if (strspn(digit, "0123456789abcdefABCDEF") != 2) + goto inval; + if (kstrtou8(digit, 16, &a->key[i])) + goto inval; + } + } + + return 0; +inval: + *error = error_inval; + return -EINVAL; +nomem: + *error = "Out of memory for an argument"; + return -ENOMEM; +} + +static int get_mac(struct crypto_shash **hash, struct alg_spec *a, char **error, + char *error_alg, char *error_key) +{ + int r; + + if (a->alg_string) { + *hash = crypto_alloc_shash(a->alg_string, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(*hash)) { + *error = error_alg; + r = PTR_ERR(*hash); + *hash = NULL; + return r; + } + + if (a->key) { + r = crypto_shash_setkey(*hash, a->key, a->key_size); + if (r) { + *error = error_key; + return r; + } + } + } + + return 0; +} + +/* + * Construct a integrity mapping: <dev_path> <offset> <tag_size> + * + * Arguments: + * device + * offset from the start of the device + * tag size + * D - direct writes, J - journal writes + * number of optional arguments + * optional arguments: + * journal-sectors + * interleave-sectors + * buffer-sectors + * journal-watermark + * commit-time + * internal-hash + * journal-crypt + * journal-mac + */ +static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) +{ + struct dm_integrity_c *ic; + char dummy; + int r; + unsigned i; + unsigned extra_args; + struct dm_arg_set as; + static struct dm_arg _args[] = { + {0, 7, "Invalid number of feature args"}, + }; + unsigned journal_sectors, interleave_sectors, buffer_sectors, journal_watermark, sync_msec; + bool should_write_sb; + __u64 journal_pages, journal_desc_size, journal_tree_size; + __u64 threshold; + unsigned long long start; + +#define DIRECT_ARGUMENTS 4 + + if (argc <= DIRECT_ARGUMENTS) { + ti->error = "Invalid argument count"; + return -EINVAL; + } + + ic = kzalloc(sizeof(struct dm_integrity_c), GFP_KERNEL); + if (!ic) { + ti->error = "Cannot allocate integrity context"; + return -ENOMEM; + } + ti->private = ic; + ti->per_io_data_size = sizeof(struct dm_integrity_io); + + ic->commit_ids[0] = cpu_to_le64(0x1111111111111111ULL); + ic->commit_ids[1] = cpu_to_le64(0x2222222222222222ULL); + ic->commit_ids[2] = cpu_to_le64(0x3333333333333333ULL); + ic->commit_ids[3] = cpu_to_le64(0x4444444444444444ULL); + + ic->in_progress = RB_ROOT; + init_waitqueue_head(&ic->endio_wait); + bio_list_init(&ic->flush_bio_list); + init_waitqueue_head(&ic->copy_to_journal_wait); + init_completion(&ic->crypto_backoff); + + r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &ic->dev); + if (r) { + ti->error = "Device lookup failed"; + goto bad; + } + + if (sscanf(argv[1], "%llu%c", &start, &dummy) != 1 || start != (sector_t)start) { + ti->error = "Invalid starting offset"; + r = -EINVAL; + goto bad; + } + ic->start = start; + + if (strcmp(argv[2], "-")) { + if (sscanf(argv[2], "%u%c", &ic->tag_size, &dummy) != 1 || !ic->tag_size) { + ti->error = "Invalid tag size"; + r = -EINVAL; + goto bad; + } + } + + if (!strcmp(argv[3], "J") || !strcmp(argv[3], "D")) + ic->mode = argv[3][0]; + else { + ti->error = "Invalid mode (expecting J or D)"; + r = -EINVAL; + goto bad; + } + + ic->device_sectors = i_size_read(ic->dev->bdev->bd_inode) >> SECTOR_SHIFT; + journal_sectors = min((sector_t)DEFAULT_MAX_JOURNAL_SECTORS, + ic->device_sectors >> DEFAULT_JOURNAL_SIZE_FACTOR); + interleave_sectors = DEFAULT_INTERLEAVE_SECTORS; + buffer_sectors = DEFAULT_BUFFER_SECTORS; + journal_watermark = DEFAULT_JOURNAL_WATERMARK; + sync_msec = DEFAULT_SYNC_MSEC; + + as.argc = argc - DIRECT_ARGUMENTS; + as.argv = argv + DIRECT_ARGUMENTS; + r = dm_read_arg_group(_args, &as, &extra_args, &ti->error); + if (r) + goto bad; + + while (extra_args--) { + const char *opt_string; + unsigned val; + opt_string = dm_shift_arg(&as); + if (!opt_string) { + r = -EINVAL; + ti->error = "Not enough feature arguments"; + goto bad; + } + if (sscanf(opt_string, "journal-sectors:%u%c", &val, &dummy) == 1) + journal_sectors = val; + else if (sscanf(opt_string, "interleave-sectors:%u%c", &val, &dummy) == 1) + interleave_sectors = val; + else if (sscanf(opt_string, "buffer-sectors:%u%c", &val, &dummy) == 1) + buffer_sectors = val; + else if (sscanf(opt_string, "journal-watermark:%u%c", &val, &dummy) == 1 && val <= 100) + journal_watermark = val; + else if (sscanf(opt_string, "commit-time:%u%c", &val, &dummy) == 1) + sync_msec = val; + else if (!memcmp(opt_string, "internal-hash:", strlen("internal-hash:"))) { + r = get_alg_and_key(opt_string, &ic->internal_hash_alg, &ti->error, + "Invalid internal-hash argument"); + if (r) + goto bad; + } else if (!memcmp(opt_string, "journal-crypt:", strlen("journal-crypt:"))) { + r = get_alg_and_key(opt_string, &ic->journal_crypt_alg, &ti->error, + "Invalid journal-crypt argument"); + if (r) + goto bad; + } else if (!memcmp(opt_string, "journal-mac:", strlen("journal-mac:"))) { + r = get_alg_and_key(opt_string, &ic->journal_mac_alg, &ti->error, + "Invalid journal-mac argument"); + if (r) + goto bad; + } else { + r = -EINVAL; + ti->error = "Invalid argument"; + goto bad; + } + } + + r = get_mac(&ic->internal_hash, &ic->internal_hash_alg, &ti->error, + "Invalid internal hash", "Error setting internal hash key"); + if (r) + goto bad; + + r = get_mac(&ic->journal_mac, &ic->journal_mac_alg, &ti->error, + "Invalid journal mac", "Error setting journal mac key"); + if (r) + goto bad; + + if (!ic->tag_size) { + if (!ic->internal_hash) { + ti->error = "Unknown tag size"; + r = -EINVAL; + goto bad; + } + ic->tag_size = crypto_shash_digestsize(ic->internal_hash); + } + if (ic->tag_size > MAX_TAG_SIZE) { + ti->error = "Too big tag size"; + r = -EINVAL; + goto bad; + } + if (!(ic->tag_size & (ic->tag_size - 1))) + ic->log2_tag_size = __ffs(ic->tag_size); + else + ic->log2_tag_size = -1; + + ic->autocommit_jiffies = msecs_to_jiffies(sync_msec); + ic->autocommit_msec = sync_msec; + setup_timer(&ic->autocommit_timer, autocommit_fn, (unsigned long)ic); + + ic->io = dm_io_client_create(); + if (IS_ERR(ic->io)) { + r = PTR_ERR(ic->io); + ic->io = NULL; + ti->error = "Cannot allocate dm io"; + goto bad; + } + + ic->journal_io_mempool = mempool_create_slab_pool(JOURNAL_IO_MEMPOOL, journal_io_cache); + if (!ic->journal_io_mempool) { + r = -ENOMEM; + ti->error = "Cannot allocate mempool"; + goto bad; + } + + ic->metadata_wq = alloc_workqueue("dm-integrity-metadata", + WQ_MEM_RECLAIM, METADATA_WORKQUEUE_MAX_ACTIVE); + if (!ic->metadata_wq) { + ti->error = "Cannot allocate workqueue"; + r = -ENOMEM; + goto bad; + } + + /* + * If this workqueue were percpu, it would cause bio reordering + * and reduced performance. + */ + ic->wait_wq = alloc_workqueue("dm-integrity-wait", WQ_MEM_RECLAIM | WQ_UNBOUND, 1); + if (!ic->wait_wq) { + ti->error = "Cannot allocate workqueue"; + r = -ENOMEM; + goto bad; + } + + ic->commit_wq = alloc_workqueue("dm-integrity-commit", WQ_MEM_RECLAIM, 1); + if (!ic->commit_wq) { + ti->error = "Cannot allocate workqueue"; + r = -ENOMEM; + goto bad; + } + INIT_WORK(&ic->commit_work, integrity_commit); + + if (ic->mode == 'J') { + ic->writer_wq = alloc_workqueue("dm-integrity-writer", WQ_MEM_RECLAIM, 1); + if (!ic->writer_wq) { + ti->error = "Cannot allocate workqueue"; + r = -ENOMEM; + goto bad; + } + INIT_WORK(&ic->writer_work, integrity_writer); + } + + ic->sb = alloc_pages_exact(SB_SECTORS << SECTOR_SHIFT, GFP_KERNEL); + if (!ic->sb) { + r = -ENOMEM; + ti->error = "Cannot allocate superblock area"; + goto bad; + } + + r = sync_rw_sb(ic, REQ_OP_READ, 0); + if (r) { + ti->error = "Error reading superblock"; + goto bad; + } + if (!memcmp(ic->sb->magic, SB_MAGIC, 8)) { + should_write_sb = false; + } else { + for (i = 0; i < 512; i += 8) { + if (*(__u64 *)((__u8 *)ic->sb + i)) { + r = -EINVAL; + ti->error = "The device is not initialized"; + goto bad; + } + } + + r = initialize_superblock(ic, journal_sectors, interleave_sectors); + if (r) { + ti->error = "Could not initialize superblock"; + goto bad; + } + should_write_sb = true; + } + + if (ic->sb->version != SB_VERSION) { + r = -EINVAL; + ti->error = "Unknown version"; + goto bad; + } + if (le16_to_cpu(ic->sb->integrity_tag_size) != ic->tag_size) { + r = -EINVAL; + ti->error = "Invalid tag size"; + goto bad; + } + /* make sure that ti->max_io_len doesn't overflow */ + if (ic->sb->log2_interleave_sectors < MIN_INTERLEAVE_SECTORS || + ic->sb->log2_interleave_sectors > MAX_INTERLEAVE_SECTORS) { + r = -EINVAL; + ti->error = "Invalid interleave_sectors in the superblock"; + goto bad; + } + ic->provided_data_sectors = le64_to_cpu(ic->sb->provided_data_sectors); + if (ic->provided_data_sectors != le64_to_cpu(ic->sb->provided_data_sectors)) { + /* test for overflow */ + r = -EINVAL; + ti->error = "The superblock has 64-bit device size, but the kernel was compiled with 32-bit sectors"; + goto bad; + } + if (!!(ic->sb->flags & cpu_to_le32(SB_FLAG_HAVE_JOURNAL_MAC)) != !!ic->journal_mac_alg.alg_string) { + r = -EINVAL; + ti->error = "Journal mac mismatch"; + goto bad; + } + r = calculate_device_limits(ic); + if (r) { + ti->error = "The device is too small"; + goto bad; + } + + if (!buffer_sectors) + buffer_sectors = 1; + ic->log2_buffer_sectors = min3((int)__fls(buffer_sectors), (int)__ffs(ic->metadata_run), 31 - SECTOR_SHIFT); + + threshold = (__u64)ic->journal_entries * (100 - journal_watermark); + threshold += 50; + do_div(threshold, 100); + ic->free_sectors_threshold = threshold; + + DEBUG_print("initialized:\n"); + DEBUG_print(" integrity_tag_size %u\n", le16_to_cpu(ic->sb->integrity_tag_size)); + DEBUG_print(" journal_entry_size %u\n", ic->journal_entry_size); + DEBUG_print(" journal_entries_per_sector %u\n", ic->journal_entries_per_sector); + DEBUG_print(" journal_section_entries %u\n", ic->journal_section_entries); + DEBUG_print(" journal_section_sectors %u\n", ic->journal_section_sectors); + DEBUG_print(" journal_sections %u\n", (unsigned)le32_to_cpu(ic->sb->journal_sections)); + DEBUG_print(" journal_entries %u\n", ic->journal_entries); + DEBUG_print(" log2_interleave_sectors %d\n", ic->sb->log2_interleave_sectors); + DEBUG_print(" device_sectors 0x%llx\n", (unsigned long long)ic->device_sectors); + DEBUG_print(" initial_sectors 0x%x\n", ic->initial_sectors); + DEBUG_print(" metadata_run 0x%x\n", ic->metadata_run); + DEBUG_print(" log2_metadata_run %d\n", ic->log2_metadata_run); + DEBUG_print(" provided_data_sectors 0x%llx (%llu)\n", (unsigned long long)ic->provided_data_sectors, + (unsigned long long)ic->provided_data_sectors); + DEBUG_print(" log2_buffer_sectors %u\n", ic->log2_buffer_sectors); + + ic->bufio = dm_bufio_client_create(ic->dev->bdev, 1U << (SECTOR_SHIFT + ic->log2_buffer_sectors), + 1, 0, NULL, NULL); + if (IS_ERR(ic->bufio)) { + r = PTR_ERR(ic->bufio); + ti->error = "Cannot initialize dm-bufio"; + ic->bufio = NULL; + goto bad; + } + dm_bufio_set_sector_offset(ic->bufio, ic->start + ic->initial_sectors); + + journal_pages = roundup((__u64)ic->journal_sections * ic->journal_section_sectors, + PAGE_SIZE >> SECTOR_SHIFT) >> (PAGE_SHIFT - SECTOR_SHIFT); + journal_desc_size = journal_pages * sizeof(struct page_list); + if (journal_pages >= totalram_pages - totalhigh_pages || journal_desc_size > ULONG_MAX) { + ti->error = "Journal doesn't fit into memory"; + r = -ENOMEM; + goto bad; + } + ic->journal_pages = journal_pages; + + ic->journal = dm_integrity_alloc_page_list(ic); + if (!ic->journal) { + ti->error = "Could not allocate memory for journal"; + r = -ENOMEM; + goto bad; + } + if (ic->journal_crypt_alg.alg_string) { + unsigned ivsize, blocksize; + struct journal_completion comp; + comp.ic = ic; + + ic->journal_crypt = crypto_alloc_skcipher(ic->journal_crypt_alg.alg_string, 0, 0); + if (IS_ERR(ic->journal_crypt)) { + ti->error = "Invalid journal cipher"; + r = PTR_ERR(ic->journal_crypt); + ic->journal_crypt = NULL; + goto bad; + } + ivsize = crypto_skcipher_ivsize(ic->journal_crypt); + blocksize = crypto_skcipher_blocksize(ic->journal_crypt); + + if (ic->journal_crypt_alg.key) { + r = crypto_skcipher_setkey(ic->journal_crypt, ic->journal_crypt_alg.key, + ic->journal_crypt_alg.key_size); + if (r) { + ti->error = "Error setting encryption key"; + goto bad; + } + } + DEBUG_print("cipher %s, block size %u iv size %u\n", + ic->journal_crypt_alg.alg_string, blocksize, ivsize); + + ic->journal_io = dm_integrity_alloc_page_list(ic); + if (!ic->journal_io) { + ti->error = "Could not allocate memory for journal io"; + r = -ENOMEM; + goto bad; + } + + if (blocksize == 1) { + struct scatterlist *sg; + SKCIPHER_REQUEST_ON_STACK(req, ic->journal_crypt); + unsigned char iv[ivsize]; + skcipher_request_set_tfm(req, ic->journal_crypt); + + ic->journal_xor = dm_integrity_alloc_page_list(ic); + if (!ic->journal_xor) { + ti->error = "Could not allocate memory for journal xor"; + r = -ENOMEM; + goto bad; + } + + sg = dm_integrity_kvmalloc((ic->journal_pages + 1) * sizeof(struct scatterlist), 0); + if (!sg) { + ti->error = "Unable to allocate sg list"; + r = -ENOMEM; + goto bad; + } + sg_init_table(sg, ic->journal_pages + 1); + for (i = 0; i < ic->journal_pages; i++) { + char *va = lowmem_page_address(ic->journal_xor[i].page); + clear_page(va); + sg_set_buf(&sg[i], va, PAGE_SIZE); + } + sg_set_buf(&sg[i], &ic->commit_ids, sizeof ic->commit_ids); + memset(iv, 0x00, ivsize); + + skcipher_request_set_crypt(req, sg, sg, PAGE_SIZE * ic->journal_pages + sizeof ic->commit_ids, iv); + comp.comp = COMPLETION_INITIALIZER_ONSTACK(comp.comp); + comp.in_flight = (atomic_t)ATOMIC_INIT(1); + if (do_crypt(true, req, &comp)) + wait_for_completion(&comp.comp); + kvfree(sg); + if ((r = dm_integrity_failed(ic))) { + ti->error = "Unable to encrypt journal"; + goto bad; + } + DEBUG_bytes(lowmem_page_address(ic->journal_xor[0].page), 64, "xor data"); + + crypto_free_skcipher(ic->journal_crypt); + ic->journal_crypt = NULL; + } else { + SKCIPHER_REQUEST_ON_STACK(req, ic->journal_crypt); + unsigned char iv[ivsize]; + unsigned crypt_len = roundup(ivsize, blocksize); + unsigned char crypt_data[crypt_len]; + + skcipher_request_set_tfm(req, ic->journal_crypt); + + ic->journal_scatterlist = dm_integrity_alloc_journal_scatterlist(ic, ic->journal); + if (!ic->journal_scatterlist) { + ti->error = "Unable to allocate sg list"; + r = -ENOMEM; + goto bad; + } + ic->journal_io_scatterlist = dm_integrity_alloc_journal_scatterlist(ic, ic->journal_io); + if (!ic->journal_io_scatterlist) { + ti->error = "Unable to allocate sg list"; + r = -ENOMEM; + goto bad; + } + ic->sk_requests = dm_integrity_kvmalloc(ic->journal_sections * sizeof(struct skcipher_request *), __GFP_ZERO); + if (!ic->sk_requests) { + ti->error = "Unable to allocate sk requests"; + r = -ENOMEM; + goto bad; + } + for (i = 0; i < ic->journal_sections; i++) { + struct scatterlist sg; + struct skcipher_request *section_req; + __u32 section_le = cpu_to_le32(i); + + memset(iv, 0x00, ivsize); + memset(crypt_data, 0x00, crypt_len); + memcpy(crypt_data, §ion_le, min((size_t)crypt_len, sizeof(section_le))); + + sg_init_one(&sg, crypt_data, crypt_len); + skcipher_request_set_crypt(req, &sg, &sg, crypt_len, iv); + comp.comp = COMPLETION_INITIALIZER_ONSTACK(comp.comp); + comp.in_flight = (atomic_t)ATOMIC_INIT(1); + if (do_crypt(true, req, &comp)) + wait_for_completion(&comp.comp); + + if ((r = dm_integrity_failed(ic))) { + ti->error = "Unable to generate iv"; + goto bad; + } + + section_req = skcipher_request_alloc(ic->journal_crypt, GFP_KERNEL); + if (!section_req) { + ti->error = "Unable to allocate crypt request"; + r = -ENOMEM; + goto bad; + } + section_req->iv = kmalloc(ivsize * 2, GFP_KERNEL); + if (!section_req->iv) { + skcipher_request_free(section_req); + ti->error = "Unable to allocate iv"; + r = -ENOMEM; + goto bad; + } + memcpy(section_req->iv + ivsize, crypt_data, ivsize); + section_req->cryptlen = (size_t)ic->journal_section_sectors << SECTOR_SHIFT; + ic->sk_requests[i] = section_req; + DEBUG_bytes(crypt_data, ivsize, "iv(%u)", i); + } + } + } + + for (i = 0; i < N_COMMIT_IDS; i++) { + unsigned j; +retest_commit_id: + for (j = 0; j < i; j++) { + if (ic->commit_ids[j] == ic->commit_ids[i]) { + ic->commit_ids[i] = cpu_to_le64(le64_to_cpu(ic->commit_ids[i]) + 1); + goto retest_commit_id; + } + } + DEBUG_print("commit id %u: %016llx\n", i, ic->commit_ids[i]); + } + + journal_tree_size = (__u64)ic->journal_entries * sizeof(struct journal_node); + if (journal_tree_size > ULONG_MAX) { + ti->error = "Journal doesn't fit into memory"; + r = -ENOMEM; + goto bad; + } + ic->journal_tree = dm_integrity_kvmalloc(journal_tree_size, 0); + if (!ic->journal_tree) { + ti->error = "Could not allocate memory for journal tree"; + r = -ENOMEM; + goto bad; + } + + if (should_write_sb) { + int r; + + init_journal(ic, 0, ic->journal_sections, 0); + r = dm_integrity_failed(ic); + if (unlikely(r)) { + ti->error = "Error initializing journal"; + goto bad; + } + r = sync_rw_sb(ic, REQ_OP_WRITE, REQ_FUA); + if (r) { + ti->error = "Error initializing superblock"; + goto bad; + } + ic->just_formatted = true; + } + + r = dm_set_target_max_io_len(ti, 1U << ic->sb->log2_interleave_sectors); + if (r) + goto bad; + + if (!ic->internal_hash) + dm_integrity_set(ti, ic); + + ti->num_flush_bios = 1; + ti->flush_supported = true; + + return 0; +bad: + dm_integrity_dtr(ti); + return r; +} + +static void dm_integrity_dtr(struct dm_target *ti) +{ + struct dm_integrity_c *ic = ti->private; + + BUG_ON(!RB_EMPTY_ROOT(&ic->in_progress)); + + if (ic->metadata_wq) + destroy_workqueue(ic->metadata_wq); + if (ic->wait_wq) + destroy_workqueue(ic->wait_wq); + if (ic->commit_wq) + destroy_workqueue(ic->commit_wq); + if (ic->writer_wq) + destroy_workqueue(ic->writer_wq); + if (ic->bufio) + dm_bufio_client_destroy(ic->bufio); + mempool_destroy(ic->journal_io_mempool); + if (ic->io) + dm_io_client_destroy(ic->io); + if (ic->dev) + dm_put_device(ti, ic->dev); + dm_integrity_free_page_list(ic, ic->journal); + dm_integrity_free_page_list(ic, ic->journal_io); + dm_integrity_free_page_list(ic, ic->journal_xor); + if (ic->journal_scatterlist) + dm_integrity_free_journal_scatterlist(ic, ic->journal_scatterlist); + if (ic->journal_io_scatterlist) + dm_integrity_free_journal_scatterlist(ic, ic->journal_io_scatterlist); + if (ic->sk_requests) { + unsigned i; + + for (i = 0; i < ic->journal_sections; i++) { + struct skcipher_request *req = ic->sk_requests[i]; + if (req) { + kzfree(req->iv); + skcipher_request_free(req); + } + } + kvfree(ic->sk_requests); + } + kvfree(ic->journal_tree); + if (ic->sb) + free_pages_exact(ic->sb, SB_SECTORS << SECTOR_SHIFT); + + if (ic->internal_hash) + crypto_free_shash(ic->internal_hash); + free_alg(&ic->internal_hash_alg); + + if (ic->journal_crypt) + crypto_free_skcipher(ic->journal_crypt); + free_alg(&ic->journal_crypt_alg); + + if (ic->journal_mac) + crypto_free_shash(ic->journal_mac); + free_alg(&ic->journal_mac_alg); + + kfree(ic); +} + +static struct target_type integrity_target = { + .name = "integrity", + .version = {1, 0, 0}, + .module = THIS_MODULE, + .features = DM_TARGET_SINGLETON | DM_TARGET_INTEGRITY, + .ctr = dm_integrity_ctr, + .dtr = dm_integrity_dtr, + .map = dm_integrity_map, + .postsuspend = dm_integrity_postsuspend, + .resume = dm_integrity_resume, + .status = dm_integrity_status, + .iterate_devices = dm_integrity_iterate_devices, +}; + +int __init dm_integrity_init(void) +{ + int r; + + journal_io_cache = kmem_cache_create("integrity_journal_io", + sizeof(struct journal_io), 0, 0, NULL); + if (!journal_io_cache) { + DMERR("can't allocate journal io cache"); + return -ENOMEM; + } + + r = dm_register_target(&integrity_target); + + if (r < 0) + DMERR("register failed %d", r); + + return r; +} + +void dm_integrity_exit(void) +{ + dm_unregister_target(&integrity_target); + kmem_cache_destroy(journal_io_cache); +} + +module_init(dm_integrity_init); +module_exit(dm_integrity_exit); + +MODULE_AUTHOR("Milan Broz"); +MODULE_AUTHOR("Mikulas Patocka"); +MODULE_DESCRIPTION(DM_NAME " target for integrity tags extension"); +MODULE_LICENSE("GPL"); |