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Diffstat (limited to 'fs/erofs/decompressor.c')
-rw-r--r--fs/erofs/decompressor.c120
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;
}