+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-#include "bcachefs.h"
-#include "checksum.h"
-#include "compress.h"
-#include "extents.h"
-#include "super-io.h"
-
-#include <linux/lz4.h>
-#include <linux/zlib.h>
-#include <linux/zstd.h>
-
-/* Bounce buffer: */
-struct bbuf {
- void *b;
- enum {
- BB_NONE,
- BB_VMAP,
- BB_KMALLOC,
- BB_MEMPOOL,
- } type;
- int rw;
-};
-
-static struct bbuf __bounce_alloc(struct bch_fs *c, unsigned size, int rw)
-{
- void *b;
-
- BUG_ON(size > c->opts.encoded_extent_max);
-
- b = kmalloc(size, GFP_NOFS|__GFP_NOWARN);
- if (b)
- return (struct bbuf) { .b = b, .type = BB_KMALLOC, .rw = rw };
-
- b = mempool_alloc(&c->compression_bounce[rw], GFP_NOFS);
- if (b)
- return (struct bbuf) { .b = b, .type = BB_MEMPOOL, .rw = rw };
-
- BUG();
-}
-
-static bool bio_phys_contig(struct bio *bio, struct bvec_iter start)
-{
- struct bio_vec bv;
- struct bvec_iter iter;
- void *expected_start = NULL;
-
- __bio_for_each_bvec(bv, bio, iter, start) {
- if (expected_start &&
- expected_start != page_address(bv.bv_page) + bv.bv_offset)
- return false;
-
- expected_start = page_address(bv.bv_page) +
- bv.bv_offset + bv.bv_len;
- }
-
- return true;
-}
-
-static struct bbuf __bio_map_or_bounce(struct bch_fs *c, struct bio *bio,
- struct bvec_iter start, int rw)
-{
- struct bbuf ret;
- struct bio_vec bv;
- struct bvec_iter iter;
- unsigned nr_pages = 0;
- struct page *stack_pages[16];
- struct page **pages = NULL;
- void *data;
-
- BUG_ON(start.bi_size > c->opts.encoded_extent_max);
-
- if (!PageHighMem(bio_iter_page(bio, start)) &&
- bio_phys_contig(bio, start))
- return (struct bbuf) {
- .b = page_address(bio_iter_page(bio, start)) +
- bio_iter_offset(bio, start),
- .type = BB_NONE, .rw = rw
- };
-
- /* check if we can map the pages contiguously: */
- __bio_for_each_segment(bv, bio, iter, start) {
- if (iter.bi_size != start.bi_size &&
- bv.bv_offset)
- goto bounce;
-
- if (bv.bv_len < iter.bi_size &&
- bv.bv_offset + bv.bv_len < PAGE_SIZE)
- goto bounce;
-
- nr_pages++;
- }
-
- BUG_ON(DIV_ROUND_UP(start.bi_size, PAGE_SIZE) > nr_pages);
-
- pages = nr_pages > ARRAY_SIZE(stack_pages)
- ? kmalloc_array(nr_pages, sizeof(struct page *), GFP_NOFS)
- : stack_pages;
- if (!pages)
- goto bounce;
-
- nr_pages = 0;
- __bio_for_each_segment(bv, bio, iter, start)
- pages[nr_pages++] = bv.bv_page;
-
- data = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
- if (pages != stack_pages)
- kfree(pages);
-
- if (data)
- return (struct bbuf) {
- .b = data + bio_iter_offset(bio, start),
- .type = BB_VMAP, .rw = rw
- };
-bounce:
- ret = __bounce_alloc(c, start.bi_size, rw);
-
- if (rw == READ)
- memcpy_from_bio(ret.b, bio, start);
-
- return ret;
-}
-
-static struct bbuf bio_map_or_bounce(struct bch_fs *c, struct bio *bio, int rw)
-{
- return __bio_map_or_bounce(c, bio, bio->bi_iter, rw);
-}
-
-static void bio_unmap_or_unbounce(struct bch_fs *c, struct bbuf buf)
-{
- switch (buf.type) {
- case BB_NONE:
- break;
- case BB_VMAP:
- vunmap((void *) ((unsigned long) buf.b & PAGE_MASK));
- break;
- case BB_KMALLOC:
- kfree(buf.b);
- break;
- case BB_MEMPOOL:
- mempool_free(buf.b, &c->compression_bounce[buf.rw]);
- break;
- }
-}
-
-static inline void zlib_set_workspace(z_stream *strm, void *workspace)
-{
-#ifdef __KERNEL__
- strm->workspace = workspace;
-#endif
-}
-
-static int __bio_uncompress(struct bch_fs *c, struct bio *src,
- void *dst_data, struct bch_extent_crc_unpacked crc)
-{
- struct bbuf src_data = { NULL };
- size_t src_len = src->bi_iter.bi_size;
- size_t dst_len = crc.uncompressed_size << 9;
- void *workspace;
- int ret;
-
- src_data = bio_map_or_bounce(c, src, READ);
-
- switch (crc.compression_type) {
- case BCH_COMPRESSION_TYPE_lz4_old:
- case BCH_COMPRESSION_TYPE_lz4:
- ret = LZ4_decompress_safe_partial(src_data.b, dst_data,
- src_len, dst_len, dst_len);
- if (ret != dst_len)
- goto err;
- break;
- case BCH_COMPRESSION_TYPE_gzip: {
- z_stream strm = {
- .next_in = src_data.b,
- .avail_in = src_len,
- .next_out = dst_data,
- .avail_out = dst_len,
- };
-
- workspace = mempool_alloc(&c->decompress_workspace, GFP_NOFS);
-
- zlib_set_workspace(&strm, workspace);
- zlib_inflateInit2(&strm, -MAX_WBITS);
- ret = zlib_inflate(&strm, Z_FINISH);
-
- mempool_free(workspace, &c->decompress_workspace);
-
- if (ret != Z_STREAM_END)
- goto err;
- break;
- }
- case BCH_COMPRESSION_TYPE_zstd: {
- ZSTD_DCtx *ctx;
- size_t real_src_len = le32_to_cpup(src_data.b);
-
- if (real_src_len > src_len - 4)
- goto err;
-
- workspace = mempool_alloc(&c->decompress_workspace, GFP_NOFS);
- ctx = zstd_init_dctx(workspace, zstd_dctx_workspace_bound());
-
- ret = zstd_decompress_dctx(ctx,
- dst_data, dst_len,
- src_data.b + 4, real_src_len);
-
- mempool_free(workspace, &c->decompress_workspace);
-
- if (ret != dst_len)
- goto err;
- break;
- }
- default:
- BUG();
- }
- ret = 0;
-out:
- bio_unmap_or_unbounce(c, src_data);
- return ret;
-err:
- ret = -EIO;
- goto out;
-}
-
-int bch2_bio_uncompress_inplace(struct bch_fs *c, struct bio *bio,
- struct bch_extent_crc_unpacked *crc)
-{
- struct bbuf data = { NULL };
- size_t dst_len = crc->uncompressed_size << 9;
-
- /* bio must own its pages: */
- BUG_ON(!bio->bi_vcnt);
- BUG_ON(DIV_ROUND_UP(crc->live_size, PAGE_SECTORS) > bio->bi_max_vecs);
-
- if (crc->uncompressed_size << 9 > c->opts.encoded_extent_max ||
- crc->compressed_size << 9 > c->opts.encoded_extent_max) {
- bch_err(c, "error rewriting existing data: extent too big");
- return -EIO;
- }
-
- data = __bounce_alloc(c, dst_len, WRITE);
-
- if (__bio_uncompress(c, bio, data.b, *crc)) {
- if (!c->opts.no_data_io)
- bch_err(c, "error rewriting existing data: decompression error");
- bio_unmap_or_unbounce(c, data);
- return -EIO;
- }
-
- /*
- * XXX: don't have a good way to assert that the bio was allocated with
- * enough space, we depend on bch2_move_extent doing the right thing
- */
- bio->bi_iter.bi_size = crc->live_size << 9;
-
- memcpy_to_bio(bio, bio->bi_iter, data.b + (crc->offset << 9));
-
- crc->csum_type = 0;
- crc->compression_type = 0;
- crc->compressed_size = crc->live_size;
- crc->uncompressed_size = crc->live_size;
- crc->offset = 0;
- crc->csum = (struct bch_csum) { 0, 0 };
-
- bio_unmap_or_unbounce(c, data);
- return 0;
-}
-
-int bch2_bio_uncompress(struct bch_fs *c, struct bio *src,
- struct bio *dst, struct bvec_iter dst_iter,
- struct bch_extent_crc_unpacked crc)
-{
- struct bbuf dst_data = { NULL };
- size_t dst_len = crc.uncompressed_size << 9;
- int ret;
-
- if (crc.uncompressed_size << 9 > c->opts.encoded_extent_max ||
- crc.compressed_size << 9 > c->opts.encoded_extent_max)
- return -EIO;
-
- dst_data = dst_len == dst_iter.bi_size
- ? __bio_map_or_bounce(c, dst, dst_iter, WRITE)
- : __bounce_alloc(c, dst_len, WRITE);
-
- ret = __bio_uncompress(c, src, dst_data.b, crc);
- if (ret)
- goto err;
-
- if (dst_data.type != BB_NONE &&
- dst_data.type != BB_VMAP)
- memcpy_to_bio(dst, dst_iter, dst_data.b + (crc.offset << 9));
-err:
- bio_unmap_or_unbounce(c, dst_data);
- return ret;
-}
-
-static int attempt_compress(struct bch_fs *c,
- void *workspace,
- void *dst, size_t dst_len,
- void *src, size_t src_len,
- struct bch_compression_opt compression)
-{
- enum bch_compression_type compression_type =
- __bch2_compression_opt_to_type[compression.type];
-
- switch (compression_type) {
- case BCH_COMPRESSION_TYPE_lz4:
- if (compression.level < LZ4HC_MIN_CLEVEL) {
- int len = src_len;
- int ret = LZ4_compress_destSize(
- src, dst,
- &len, dst_len,
- workspace);
- if (len < src_len)
- return -len;
-
- return ret;
- } else {
- int ret = LZ4_compress_HC(
- src, dst,
- src_len, dst_len,
- compression.level,
- workspace);
-
- return ret ?: -1;
- }
- case BCH_COMPRESSION_TYPE_gzip: {
- z_stream strm = {
- .next_in = src,
- .avail_in = src_len,
- .next_out = dst,
- .avail_out = dst_len,
- };
-
- zlib_set_workspace(&strm, workspace);
- zlib_deflateInit2(&strm,
- compression.level
- ? clamp_t(unsigned, compression.level,
- Z_BEST_SPEED, Z_BEST_COMPRESSION)
- : Z_DEFAULT_COMPRESSION,
- Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL,
- Z_DEFAULT_STRATEGY);
-
- if (zlib_deflate(&strm, Z_FINISH) != Z_STREAM_END)
- return 0;
-
- if (zlib_deflateEnd(&strm) != Z_OK)
- return 0;
-
- return strm.total_out;
- }
- case BCH_COMPRESSION_TYPE_zstd: {
- /*
- * rescale:
- * zstd max compression level is 22, our max level is 15
- */
- unsigned level = min((compression.level * 3) / 2, zstd_max_clevel());
- ZSTD_parameters params = zstd_get_params(level, c->opts.encoded_extent_max);
- ZSTD_CCtx *ctx = zstd_init_cctx(workspace, c->zstd_workspace_size);
-
- /*
- * ZSTD requires that when we decompress we pass in the exact
- * compressed size - rounding it up to the nearest sector
- * doesn't work, so we use the first 4 bytes of the buffer for
- * that.
- *
- * Additionally, the ZSTD code seems to have a bug where it will
- * write just past the end of the buffer - so subtract a fudge
- * factor (7 bytes) from the dst buffer size to account for
- * that.
- */
- size_t len = zstd_compress_cctx(ctx,
- dst + 4, dst_len - 4 - 7,
- src, src_len,
- ¶ms);
- if (zstd_is_error(len))
- return 0;
-
- *((__le32 *) dst) = cpu_to_le32(len);
- return len + 4;
- }
- default:
- BUG();
- }
-}
-
-static unsigned __bio_compress(struct bch_fs *c,
- struct bio *dst, size_t *dst_len,
- struct bio *src, size_t *src_len,
- struct bch_compression_opt compression)
-{
- struct bbuf src_data = { NULL }, dst_data = { NULL };
- void *workspace;
- enum bch_compression_type compression_type =
- __bch2_compression_opt_to_type[compression.type];
- unsigned pad;
- int ret = 0;
-
- BUG_ON(compression_type >= BCH_COMPRESSION_TYPE_NR);
- BUG_ON(!mempool_initialized(&c->compress_workspace[compression_type]));
-
- /* If it's only one block, don't bother trying to compress: */
- if (src->bi_iter.bi_size <= c->opts.block_size)
- return BCH_COMPRESSION_TYPE_incompressible;
-
- dst_data = bio_map_or_bounce(c, dst, WRITE);
- src_data = bio_map_or_bounce(c, src, READ);
-
- workspace = mempool_alloc(&c->compress_workspace[compression_type], GFP_NOFS);
-
- *src_len = src->bi_iter.bi_size;
- *dst_len = dst->bi_iter.bi_size;
-
- /*
- * XXX: this algorithm sucks when the compression code doesn't tell us
- * how much would fit, like LZ4 does:
- */
- while (1) {
- if (*src_len <= block_bytes(c)) {
- ret = -1;
- break;
- }
-
- ret = attempt_compress(c, workspace,
- dst_data.b, *dst_len,
- src_data.b, *src_len,
- compression);
- if (ret > 0) {
- *dst_len = ret;
- ret = 0;
- break;
- }
-
- /* Didn't fit: should we retry with a smaller amount? */
- if (*src_len <= *dst_len) {
- ret = -1;
- break;
- }
-
- /*
- * If ret is negative, it's a hint as to how much data would fit
- */
- BUG_ON(-ret >= *src_len);
-
- if (ret < 0)
- *src_len = -ret;
- else
- *src_len -= (*src_len - *dst_len) / 2;
- *src_len = round_down(*src_len, block_bytes(c));
- }
-
- mempool_free(workspace, &c->compress_workspace[compression_type]);
-
- if (ret)
- goto err;
-
- /* Didn't get smaller: */
- if (round_up(*dst_len, block_bytes(c)) >= *src_len)
- goto err;
-
- pad = round_up(*dst_len, block_bytes(c)) - *dst_len;
-
- memset(dst_data.b + *dst_len, 0, pad);
- *dst_len += pad;
-
- if (dst_data.type != BB_NONE &&
- dst_data.type != BB_VMAP)
- memcpy_to_bio(dst, dst->bi_iter, dst_data.b);
-
- BUG_ON(!*dst_len || *dst_len > dst->bi_iter.bi_size);
- BUG_ON(!*src_len || *src_len > src->bi_iter.bi_size);
- BUG_ON(*dst_len & (block_bytes(c) - 1));
- BUG_ON(*src_len & (block_bytes(c) - 1));
- ret = compression_type;
-out:
- bio_unmap_or_unbounce(c, src_data);
- bio_unmap_or_unbounce(c, dst_data);
- return ret;
-err:
- ret = BCH_COMPRESSION_TYPE_incompressible;
- goto out;
-}
-
-unsigned bch2_bio_compress(struct bch_fs *c,
- struct bio *dst, size_t *dst_len,
- struct bio *src, size_t *src_len,
- unsigned compression_opt)
-{
- unsigned orig_dst = dst->bi_iter.bi_size;
- unsigned orig_src = src->bi_iter.bi_size;
- unsigned compression_type;
-
- /* Don't consume more than BCH_ENCODED_EXTENT_MAX from @src: */
- src->bi_iter.bi_size = min_t(unsigned, src->bi_iter.bi_size,
- c->opts.encoded_extent_max);
- /* Don't generate a bigger output than input: */
- dst->bi_iter.bi_size = min(dst->bi_iter.bi_size, src->bi_iter.bi_size);
-
- compression_type =
- __bio_compress(c, dst, dst_len, src, src_len,
- bch2_compression_decode(compression_opt));
-
- dst->bi_iter.bi_size = orig_dst;
- src->bi_iter.bi_size = orig_src;
- return compression_type;
-}
-
-static int __bch2_fs_compress_init(struct bch_fs *, u64);
-
-#define BCH_FEATURE_none 0
-
-static const unsigned bch2_compression_opt_to_feature[] = {
-#define x(t, n) [BCH_COMPRESSION_OPT_##t] = BCH_FEATURE_##t,
- BCH_COMPRESSION_OPTS()
-#undef x
-};
-
-#undef BCH_FEATURE_none
-
-static int __bch2_check_set_has_compressed_data(struct bch_fs *c, u64 f)
-{
- int ret = 0;
-
- if ((c->sb.features & f) == f)
- return 0;
-
- mutex_lock(&c->sb_lock);
-
- if ((c->sb.features & f) == f) {
- mutex_unlock(&c->sb_lock);
- return 0;
- }
-
- ret = __bch2_fs_compress_init(c, c->sb.features|f);
- if (ret) {
- mutex_unlock(&c->sb_lock);
- return ret;
- }
-
- c->disk_sb.sb->features[0] |= cpu_to_le64(f);
- bch2_write_super(c);
- mutex_unlock(&c->sb_lock);
-
- return 0;
-}
-
-int bch2_check_set_has_compressed_data(struct bch_fs *c,
- unsigned compression_opt)
-{
- unsigned compression_type = bch2_compression_decode(compression_opt).type;
-
- BUG_ON(compression_type >= ARRAY_SIZE(bch2_compression_opt_to_feature));
-
- return compression_type
- ? __bch2_check_set_has_compressed_data(c,
- 1ULL << bch2_compression_opt_to_feature[compression_type])
- : 0;
-}
-
-void bch2_fs_compress_exit(struct bch_fs *c)
-{
- unsigned i;
-
- mempool_exit(&c->decompress_workspace);
- for (i = 0; i < ARRAY_SIZE(c->compress_workspace); i++)
- mempool_exit(&c->compress_workspace[i]);
- mempool_exit(&c->compression_bounce[WRITE]);
- mempool_exit(&c->compression_bounce[READ]);
-}
-
-static int __bch2_fs_compress_init(struct bch_fs *c, u64 features)
-{
- size_t decompress_workspace_size = 0;
- ZSTD_parameters params = zstd_get_params(zstd_max_clevel(),
- c->opts.encoded_extent_max);
-
- c->zstd_workspace_size = zstd_cctx_workspace_bound(¶ms.cParams);
-
- struct {
- unsigned feature;
- enum bch_compression_type type;
- size_t compress_workspace;
- size_t decompress_workspace;
- } compression_types[] = {
- { BCH_FEATURE_lz4, BCH_COMPRESSION_TYPE_lz4,
- max_t(size_t, LZ4_MEM_COMPRESS, LZ4HC_MEM_COMPRESS),
- 0 },
- { BCH_FEATURE_gzip, BCH_COMPRESSION_TYPE_gzip,
- zlib_deflate_workspacesize(MAX_WBITS, DEF_MEM_LEVEL),
- zlib_inflate_workspacesize(), },
- { BCH_FEATURE_zstd, BCH_COMPRESSION_TYPE_zstd,
- c->zstd_workspace_size,
- zstd_dctx_workspace_bound() },
- }, *i;
- bool have_compressed = false;
-
- for (i = compression_types;
- i < compression_types + ARRAY_SIZE(compression_types);
- i++)
- have_compressed |= (features & (1 << i->feature)) != 0;
-
- if (!have_compressed)
- return 0;
-
- if (!mempool_initialized(&c->compression_bounce[READ]) &&
- mempool_init_kvpmalloc_pool(&c->compression_bounce[READ],
- 1, c->opts.encoded_extent_max))
- return -BCH_ERR_ENOMEM_compression_bounce_read_init;
-
- if (!mempool_initialized(&c->compression_bounce[WRITE]) &&
- mempool_init_kvpmalloc_pool(&c->compression_bounce[WRITE],
- 1, c->opts.encoded_extent_max))
- return -BCH_ERR_ENOMEM_compression_bounce_write_init;
-
- for (i = compression_types;
- i < compression_types + ARRAY_SIZE(compression_types);
- i++) {
- decompress_workspace_size =
- max(decompress_workspace_size, i->decompress_workspace);
-
- if (!(features & (1 << i->feature)))
- continue;
-
- if (mempool_initialized(&c->compress_workspace[i->type]))
- continue;
-
- if (mempool_init_kvpmalloc_pool(
- &c->compress_workspace[i->type],
- 1, i->compress_workspace))
- return -BCH_ERR_ENOMEM_compression_workspace_init;
- }
-
- if (!mempool_initialized(&c->decompress_workspace) &&
- mempool_init_kvpmalloc_pool(&c->decompress_workspace,
- 1, decompress_workspace_size))
- return -BCH_ERR_ENOMEM_decompression_workspace_init;
-
- return 0;
-}
-
-static u64 compression_opt_to_feature(unsigned v)
-{
- unsigned type = bch2_compression_decode(v).type;
-
- return BIT_ULL(bch2_compression_opt_to_feature[type]);
-}
-
-int bch2_fs_compress_init(struct bch_fs *c)
-{
- u64 f = c->sb.features;
-
- f |= compression_opt_to_feature(c->opts.compression);
- f |= compression_opt_to_feature(c->opts.background_compression);
-
- return __bch2_fs_compress_init(c, f);
-}
-
-int bch2_opt_compression_parse(struct bch_fs *c, const char *_val, u64 *res,
- struct printbuf *err)
-{
- char *val = kstrdup(_val, GFP_KERNEL);
- char *p = val, *type_str, *level_str;
- struct bch_compression_opt opt = { 0 };
- int ret;
-
- if (!val)
- return -ENOMEM;
-
- type_str = strsep(&p, ":");
- level_str = p;
-
- ret = match_string(bch2_compression_opts, -1, type_str);
- if (ret < 0 && err)
- prt_str(err, "invalid compression type");
- if (ret < 0)
- goto err;
-
- opt.type = ret;
-
- if (level_str) {
- unsigned level;
-
- ret = kstrtouint(level_str, 10, &level);
- if (!ret && !opt.type && level)
- ret = -EINVAL;
- if (!ret && level > 15)
- ret = -EINVAL;
- if (ret < 0 && err)
- prt_str(err, "invalid compression level");
- if (ret < 0)
- goto err;
-
- opt.level = level;
- }
-
- *res = bch2_compression_encode(opt);
-err:
- kfree(val);
- return ret;
-}
-
-void bch2_compression_opt_to_text(struct printbuf *out, u64 v)
-{
- struct bch_compression_opt opt = bch2_compression_decode(v);
-
- if (opt.type < BCH_COMPRESSION_OPT_NR)
- prt_str(out, bch2_compression_opts[opt.type]);
- else
- prt_printf(out, "(unknown compression opt %u)", opt.type);
- if (opt.level)
- prt_printf(out, ":%u", opt.level);
-}
-
-void bch2_opt_compression_to_text(struct printbuf *out,
- struct bch_fs *c,
- struct bch_sb *sb,
- u64 v)
-{
- return bch2_compression_opt_to_text(out, v);
-}
-
-int bch2_opt_compression_validate(u64 v, struct printbuf *err)
-{
- if (!bch2_compression_opt_valid(v)) {
- prt_printf(err, "invalid compression opt %llu", v);
- return -BCH_ERR_invalid_sb_opt_compression;
- }
-
- return 0;
-}
projects / bcachefs-tools-debian / blobdiff