diff options
Diffstat (limited to 'fs/erofs/decompressor.c')
-rw-r--r-- | fs/erofs/decompressor.c | 120 |
1 files changed, 65 insertions, 55 deletions
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index af98e88908ee..072ef6a66823 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -121,11 +121,11 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx, } static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx, - void *inpage, unsigned int *inputmargin, int *maptype, - bool may_inplace) + void *inpage, void *out, unsigned int *inputmargin, + int *maptype, bool may_inplace) { struct z_erofs_decompress_req *rq = ctx->rq; - unsigned int omargin, total, i, j; + unsigned int omargin, total, i; struct page **in; void *src, *tmp; @@ -135,12 +135,13 @@ static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx, omargin < LZ4_DECOMPRESS_INPLACE_MARGIN(rq->inputsize)) goto docopy; - for (i = 0; i < ctx->inpages; ++i) { - DBG_BUGON(rq->in[i] == NULL); - for (j = 0; j < ctx->outpages - ctx->inpages + i; ++j) - if (rq->out[j] == rq->in[i]) - goto docopy; - } + for (i = 0; i < ctx->inpages; ++i) + if (rq->out[ctx->outpages - ctx->inpages + i] != + rq->in[i]) + goto docopy; + kunmap_local(inpage); + *maptype = 3; + return out + ((ctx->outpages - ctx->inpages) << PAGE_SHIFT); } if (ctx->inpages <= 1) { @@ -148,7 +149,6 @@ static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx, return inpage; } kunmap_local(inpage); - might_sleep(); src = erofs_vm_map_ram(rq->in, ctx->inpages); if (!src) return ERR_PTR(-ENOMEM); @@ -204,12 +204,12 @@ int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf, } static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx, - u8 *out) + u8 *dst) { struct z_erofs_decompress_req *rq = ctx->rq; bool support_0padding = false, may_inplace = false; unsigned int inputmargin; - u8 *headpage, *src; + u8 *out, *headpage, *src; int ret, maptype; DBG_BUGON(*rq->in == NULL); @@ -230,11 +230,12 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx, } inputmargin = rq->pageofs_in; - src = z_erofs_lz4_handle_overlap(ctx, headpage, &inputmargin, + src = z_erofs_lz4_handle_overlap(ctx, headpage, dst, &inputmargin, &maptype, may_inplace); if (IS_ERR(src)) return PTR_ERR(src); + out = dst + rq->pageofs_out; /* legacy format could compress extra data in a pcluster. */ if (rq->partial_decoding || !support_0padding) ret = LZ4_decompress_safe_partial(src + inputmargin, out, @@ -246,15 +247,9 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx, if (ret != rq->outputsize) { erofs_err(rq->sb, "failed to decompress %d in[%u, %u] out[%u]", ret, rq->inputsize, inputmargin, rq->outputsize); - - print_hex_dump(KERN_DEBUG, "[ in]: ", DUMP_PREFIX_OFFSET, - 16, 1, src + inputmargin, rq->inputsize, true); - print_hex_dump(KERN_DEBUG, "[out]: ", DUMP_PREFIX_OFFSET, - 16, 1, out, rq->outputsize, true); - if (ret >= 0) memset(out + ret, 0, rq->outputsize - ret); - ret = -EIO; + ret = -EFSCORRUPTED; } else { ret = 0; } @@ -265,7 +260,7 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx, vm_unmap_ram(src, ctx->inpages); } else if (maptype == 2) { erofs_put_pcpubuf(src); - } else { + } else if (maptype != 3) { DBG_BUGON(1); return -EFAULT; } @@ -308,7 +303,7 @@ static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, } dstmap_out: - ret = z_erofs_lz4_decompress_mem(&ctx, dst + rq->pageofs_out); + ret = z_erofs_lz4_decompress_mem(&ctx, dst); if (!dst_maptype) kunmap_local(dst); else if (dst_maptype == 2) @@ -319,43 +314,58 @@ dstmap_out: static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq, struct page **pagepool) { - const unsigned int inpages = PAGE_ALIGN(rq->inputsize) >> PAGE_SHIFT; - const unsigned int outpages = + const unsigned int nrpages_in = + PAGE_ALIGN(rq->pageofs_in + rq->inputsize) >> PAGE_SHIFT; + const unsigned int nrpages_out = PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; - const unsigned int righthalf = min_t(unsigned int, rq->outputsize, - PAGE_SIZE - rq->pageofs_out); - const unsigned int lefthalf = rq->outputsize - righthalf; - const unsigned int interlaced_offset = - rq->alg == Z_EROFS_COMPRESSION_SHIFTED ? 0 : rq->pageofs_out; - u8 *src; - - if (outpages > 2 && rq->alg == Z_EROFS_COMPRESSION_SHIFTED) { - DBG_BUGON(1); - return -EFSCORRUPTED; - } - - if (rq->out[0] == *rq->in) { - DBG_BUGON(rq->pageofs_out); - return 0; + const unsigned int bs = rq->sb->s_blocksize; + unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt; + u8 *kin; + + DBG_BUGON(rq->outputsize > rq->inputsize); + if (rq->alg == Z_EROFS_COMPRESSION_INTERLACED) { + cur = bs - (rq->pageofs_out & (bs - 1)); + pi = (rq->pageofs_in + rq->inputsize - cur) & ~PAGE_MASK; + cur = min(cur, rq->outputsize); + if (cur && rq->out[0]) { + kin = kmap_local_page(rq->in[nrpages_in - 1]); + if (rq->out[0] == rq->in[nrpages_in - 1]) { + memmove(kin + rq->pageofs_out, kin + pi, cur); + flush_dcache_page(rq->out[0]); + } else { + memcpy_to_page(rq->out[0], rq->pageofs_out, + kin + pi, cur); + } + kunmap_local(kin); + } + rq->outputsize -= cur; } - src = kmap_local_page(rq->in[inpages - 1]) + rq->pageofs_in; - if (rq->out[0]) - memcpy_to_page(rq->out[0], rq->pageofs_out, - src + interlaced_offset, righthalf); - - if (outpages > inpages) { - DBG_BUGON(!rq->out[outpages - 1]); - if (rq->out[outpages - 1] != rq->in[inpages - 1]) { - memcpy_to_page(rq->out[outpages - 1], 0, src + - (interlaced_offset ? 0 : righthalf), - lefthalf); - } else if (!interlaced_offset) { - memmove(src, src + righthalf, lefthalf); - flush_dcache_page(rq->in[inpages - 1]); - } + for (; rq->outputsize; rq->pageofs_in = 0, cur += PAGE_SIZE, ni++) { + insz = min(PAGE_SIZE - rq->pageofs_in, rq->outputsize); + rq->outputsize -= insz; + if (!rq->in[ni]) + continue; + kin = kmap_local_page(rq->in[ni]); + pi = 0; + do { + no = (rq->pageofs_out + cur + pi) >> PAGE_SHIFT; + po = (rq->pageofs_out + cur + pi) & ~PAGE_MASK; + DBG_BUGON(no >= nrpages_out); + cnt = min(insz - pi, PAGE_SIZE - po); + if (rq->out[no] == rq->in[ni]) { + memmove(kin + po, + kin + rq->pageofs_in + pi, cnt); + flush_dcache_page(rq->out[no]); + } else if (rq->out[no]) { + memcpy_to_page(rq->out[no], po, + kin + rq->pageofs_in + pi, cnt); + } + pi += cnt; + } while (pi < insz); + kunmap_local(kin); } - kunmap_local(src); + DBG_BUGON(ni > nrpages_in); return 0; } |