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Diffstat (limited to 'fs/erofs/decompressor.c')
-rw-r--r--fs/erofs/decompressor.c102
1 files changed, 36 insertions, 66 deletions
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index eb318c7ddd80..bf62e2836b60 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -7,22 +7,7 @@
#include "compress.h"
#include <linux/lz4.h>
-#ifndef LZ4_DISTANCE_MAX /* history window size */
-#define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */
-#endif
-
#define LZ4_MAX_DISTANCE_PAGES (DIV_ROUND_UP(LZ4_DISTANCE_MAX, PAGE_SIZE) + 1)
-#ifndef LZ4_DECOMPRESS_INPLACE_MARGIN
-#define LZ4_DECOMPRESS_INPLACE_MARGIN(srcsize) (((srcsize) >> 8) + 32)
-#endif
-
-struct z_erofs_lz4_decompress_ctx {
- struct z_erofs_decompress_req *rq;
- /* # of encoded, decoded pages */
- unsigned int inpages, outpages;
- /* decoded block total length (used for in-place decompression) */
- unsigned int oend;
-};
static int z_erofs_load_lz4_config(struct super_block *sb,
struct erofs_super_block *dsb, void *data, int size)
@@ -62,10 +47,9 @@ static int z_erofs_load_lz4_config(struct super_block *sb,
* Fill all gaps with bounce pages if it's a sparse page list. Also check if
* all physical pages are consecutive, which can be seen for moderate CR.
*/
-static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx,
+static int z_erofs_lz4_prepare_dstpages(struct z_erofs_decompress_req *rq,
struct page **pagepool)
{
- struct z_erofs_decompress_req *rq = ctx->rq;
struct page *availables[LZ4_MAX_DISTANCE_PAGES] = { NULL };
unsigned long bounced[DIV_ROUND_UP(LZ4_MAX_DISTANCE_PAGES,
BITS_PER_LONG)] = { 0 };
@@ -75,7 +59,7 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx,
unsigned int i, j, top;
top = 0;
- for (i = j = 0; i < ctx->outpages; ++i, ++j) {
+ for (i = j = 0; i < rq->outpages; ++i, ++j) {
struct page *const page = rq->out[i];
struct page *victim;
@@ -121,36 +105,36 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx,
return kaddr ? 1 : 0;
}
-static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx,
+static void *z_erofs_lz4_handle_overlap(struct z_erofs_decompress_req *rq,
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;
+ unsigned int oend, omargin, total, i;
struct page **in;
void *src, *tmp;
if (rq->inplace_io) {
- omargin = PAGE_ALIGN(ctx->oend) - ctx->oend;
+ oend = rq->pageofs_out + rq->outputsize;
+ omargin = PAGE_ALIGN(oend) - oend;
if (rq->partial_decoding || !may_inplace ||
omargin < LZ4_DECOMPRESS_INPLACE_MARGIN(rq->inputsize))
goto docopy;
- for (i = 0; i < ctx->inpages; ++i)
- if (rq->out[ctx->outpages - ctx->inpages + i] !=
+ for (i = 0; i < rq->inpages; ++i)
+ if (rq->out[rq->outpages - rq->inpages + i] !=
rq->in[i])
goto docopy;
kunmap_local(inpage);
*maptype = 3;
- return out + ((ctx->outpages - ctx->inpages) << PAGE_SHIFT);
+ return out + ((rq->outpages - rq->inpages) << PAGE_SHIFT);
}
- if (ctx->inpages <= 1) {
+ if (rq->inpages <= 1) {
*maptype = 0;
return inpage;
}
kunmap_local(inpage);
- src = erofs_vm_map_ram(rq->in, ctx->inpages);
+ src = erofs_vm_map_ram(rq->in, rq->inpages);
if (!src)
return ERR_PTR(-ENOMEM);
*maptype = 1;
@@ -159,7 +143,7 @@ static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx,
docopy:
/* Or copy compressed data which can be overlapped to per-CPU buffer */
in = rq->in;
- src = z_erofs_get_gbuf(ctx->inpages);
+ src = z_erofs_get_gbuf(rq->inpages);
if (!src) {
DBG_BUGON(1);
kunmap_local(inpage);
@@ -204,10 +188,8 @@ int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf,
return 0;
}
-static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx,
- u8 *dst)
+static int z_erofs_lz4_decompress_mem(struct z_erofs_decompress_req *rq, u8 *dst)
{
- struct z_erofs_decompress_req *rq = ctx->rq;
bool support_0padding = false, may_inplace = false;
unsigned int inputmargin;
u8 *out, *headpage, *src;
@@ -231,7 +213,7 @@ 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, dst, &inputmargin,
+ src = z_erofs_lz4_handle_overlap(rq, headpage, dst, &inputmargin,
&maptype, may_inplace);
if (IS_ERR(src))
return PTR_ERR(src);
@@ -258,7 +240,7 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx,
if (maptype == 0) {
kunmap_local(headpage);
} else if (maptype == 1) {
- vm_unmap_ram(src, ctx->inpages);
+ vm_unmap_ram(src, rq->inpages);
} else if (maptype == 2) {
z_erofs_put_gbuf(src);
} else if (maptype != 3) {
@@ -271,54 +253,42 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx,
static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq,
struct page **pagepool)
{
- struct z_erofs_lz4_decompress_ctx ctx;
unsigned int dst_maptype;
void *dst;
int ret;
- ctx.rq = rq;
- ctx.oend = rq->pageofs_out + rq->outputsize;
- ctx.outpages = PAGE_ALIGN(ctx.oend) >> PAGE_SHIFT;
- ctx.inpages = PAGE_ALIGN(rq->inputsize) >> PAGE_SHIFT;
-
/* one optimized fast path only for non bigpcluster cases yet */
- if (ctx.inpages == 1 && ctx.outpages == 1 && !rq->inplace_io) {
+ if (rq->inpages == 1 && rq->outpages == 1 && !rq->inplace_io) {
DBG_BUGON(!*rq->out);
dst = kmap_local_page(*rq->out);
dst_maptype = 0;
- goto dstmap_out;
- }
-
- /* general decoding path which can be used for all cases */
- ret = z_erofs_lz4_prepare_dstpages(&ctx, pagepool);
- if (ret < 0) {
- return ret;
- } else if (ret > 0) {
- dst = page_address(*rq->out);
- dst_maptype = 1;
} else {
- dst = erofs_vm_map_ram(rq->out, ctx.outpages);
- if (!dst)
- return -ENOMEM;
- dst_maptype = 2;
+ /* general decoding path which can be used for all cases */
+ ret = z_erofs_lz4_prepare_dstpages(rq, pagepool);
+ if (ret < 0)
+ return ret;
+ if (ret > 0) {
+ dst = page_address(*rq->out);
+ dst_maptype = 1;
+ } else {
+ dst = erofs_vm_map_ram(rq->out, rq->outpages);
+ if (!dst)
+ return -ENOMEM;
+ dst_maptype = 2;
+ }
}
-
-dstmap_out:
- ret = z_erofs_lz4_decompress_mem(&ctx, dst);
+ ret = z_erofs_lz4_decompress_mem(rq, dst);
if (!dst_maptype)
kunmap_local(dst);
else if (dst_maptype == 2)
- vm_unmap_ram(dst, ctx.outpages);
+ vm_unmap_ram(dst, rq->outpages);
return ret;
}
static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
struct page **pagepool)
{
- 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 nrpages_in = rq->inpages, nrpages_out = rq->outpages;
const unsigned int bs = rq->sb->s_blocksize;
unsigned int cur = 0, ni = 0, no, pi, po, insz, cnt;
u8 *kin;
@@ -343,7 +313,7 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
rq->outputsize -= cur;
}
- for (; rq->outputsize; rq->pageofs_in = 0, cur += PAGE_SIZE, ni++) {
+ for (; rq->outputsize; rq->pageofs_in = 0, cur += insz, ni++) {
insz = min(PAGE_SIZE - rq->pageofs_in, rq->outputsize);
rq->outputsize -= insz;
if (!rq->in[ni])
@@ -380,7 +350,7 @@ int z_erofs_stream_switch_bufs(struct z_erofs_stream_dctx *dctx, void **dst,
unsigned int j;
if (!dctx->avail_out) {
- if (++dctx->no >= dctx->outpages || !rq->outputsize) {
+ if (++dctx->no >= rq->outpages || !rq->outputsize) {
erofs_err(sb, "insufficient space for decompressed data");
return -EFSCORRUPTED;
}
@@ -408,7 +378,7 @@ int z_erofs_stream_switch_bufs(struct z_erofs_stream_dctx *dctx, void **dst,
}
if (dctx->inbuf_pos == dctx->inbuf_sz && rq->inputsize) {
- if (++dctx->ni >= dctx->inpages) {
+ if (++dctx->ni >= rq->inpages) {
erofs_err(sb, "invalid compressed data");
return -EFSCORRUPTED;
}
@@ -441,7 +411,7 @@ int z_erofs_stream_switch_bufs(struct z_erofs_stream_dctx *dctx, void **dst,
dctx->bounced = true;
}
- for (j = dctx->ni + 1; j < dctx->inpages; ++j) {
+ for (j = dctx->ni + 1; j < rq->inpages; ++j) {
if (rq->out[dctx->no] != rq->in[j])
continue;
tmppage = erofs_allocpage(pgpl, rq->gfp);