diff options
Diffstat (limited to 'fs/erofs/decompressor_zstd.c')
-rw-r--r-- | fs/erofs/decompressor_zstd.c | 154 |
1 files changed, 50 insertions, 104 deletions
diff --git a/fs/erofs/decompressor_zstd.c b/fs/erofs/decompressor_zstd.c index 63a23cac3af4..7e177304967e 100644 --- a/fs/erofs/decompressor_zstd.c +++ b/fs/erofs/decompressor_zstd.c @@ -34,7 +34,7 @@ again: return strm; } -void z_erofs_zstd_exit(void) +static void z_erofs_zstd_exit(void) { while (z_erofs_zstd_avail_strms) { struct z_erofs_zstd *strm, *n; @@ -49,7 +49,7 @@ void z_erofs_zstd_exit(void) } } -int __init z_erofs_zstd_init(void) +static int __init z_erofs_zstd_init(void) { /* by default, use # of possible CPUs instead */ if (!z_erofs_zstd_nstrms) @@ -72,7 +72,7 @@ int __init z_erofs_zstd_init(void) return 0; } -int z_erofs_load_zstd_config(struct super_block *sb, +static int z_erofs_load_zstd_config(struct super_block *sb, struct erofs_super_block *dsb, void *data, int size) { static DEFINE_MUTEX(zstd_resize_mutex); @@ -135,30 +135,29 @@ int z_erofs_load_zstd_config(struct super_block *sb, return strm ? -ENOMEM : 0; } -int z_erofs_zstd_decompress(struct z_erofs_decompress_req *rq, - struct page **pgpl) +static int z_erofs_zstd_decompress(struct z_erofs_decompress_req *rq, + struct page **pgpl) { - const unsigned int nrpages_out = - PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; - const unsigned int nrpages_in = - PAGE_ALIGN(rq->inputsize) >> PAGE_SHIFT; - zstd_dstream *stream; struct super_block *sb = rq->sb; - unsigned int insz, outsz, pofs; - struct z_erofs_zstd *strm; + struct z_erofs_stream_dctx dctx = { + .rq = rq, + .inpages = PAGE_ALIGN(rq->inputsize) >> PAGE_SHIFT, + .outpages = PAGE_ALIGN(rq->pageofs_out + rq->outputsize) + >> PAGE_SHIFT, + .no = -1, .ni = 0, + }; zstd_in_buffer in_buf = { NULL, 0, 0 }; zstd_out_buffer out_buf = { NULL, 0, 0 }; - u8 *kin, *kout = NULL; - bool bounced = false; - int no = -1, ni = 0, j = 0, zerr, err; + struct z_erofs_zstd *strm; + zstd_dstream *stream; + int zerr, err; /* 1. get the exact compressed size */ - kin = kmap_local_page(*rq->in); - err = z_erofs_fixup_insize(rq, kin + rq->pageofs_in, - min_t(unsigned int, rq->inputsize, - sb->s_blocksize - rq->pageofs_in)); + dctx.kin = kmap_local_page(*rq->in); + err = z_erofs_fixup_insize(rq, dctx.kin + rq->pageofs_in, + min(rq->inputsize, sb->s_blocksize - rq->pageofs_in)); if (err) { - kunmap_local(kin); + kunmap_local(dctx.kin); return err; } @@ -166,109 +165,48 @@ int z_erofs_zstd_decompress(struct z_erofs_decompress_req *rq, strm = z_erofs_isolate_strms(false); /* 3. multi-call decompress */ - insz = rq->inputsize; - outsz = rq->outputsize; stream = zstd_init_dstream(z_erofs_zstd_max_dictsize, strm->wksp, strm->wkspsz); if (!stream) { err = -EIO; goto failed_zinit; } - pofs = rq->pageofs_out; - in_buf.size = min_t(u32, insz, PAGE_SIZE - rq->pageofs_in); - insz -= in_buf.size; - in_buf.src = kin + rq->pageofs_in; + rq->fillgaps = true; /* ZSTD doesn't support NULL output buffer */ + in_buf.size = min_t(u32, rq->inputsize, PAGE_SIZE - rq->pageofs_in); + rq->inputsize -= in_buf.size; + in_buf.src = dctx.kin + rq->pageofs_in; + dctx.bounce = strm->bounce; + do { - if (out_buf.size == out_buf.pos) { - if (++no >= nrpages_out || !outsz) { - erofs_err(sb, "insufficient space for decompressed data"); - err = -EFSCORRUPTED; - break; - } + dctx.avail_out = out_buf.size - out_buf.pos; + dctx.inbuf_sz = in_buf.size; + dctx.inbuf_pos = in_buf.pos; + err = z_erofs_stream_switch_bufs(&dctx, &out_buf.dst, + (void **)&in_buf.src, pgpl); + if (err) + break; - if (kout) - kunmap_local(kout); - out_buf.size = min_t(u32, outsz, PAGE_SIZE - pofs); - outsz -= out_buf.size; - if (!rq->out[no]) { - rq->out[no] = erofs_allocpage(pgpl, rq->gfp); - if (!rq->out[no]) { - kout = NULL; - err = -ENOMEM; - break; - } - set_page_private(rq->out[no], - Z_EROFS_SHORTLIVED_PAGE); - } - kout = kmap_local_page(rq->out[no]); - out_buf.dst = kout + pofs; + if (out_buf.size == out_buf.pos) { + out_buf.size = dctx.avail_out; out_buf.pos = 0; - pofs = 0; - } - - if (in_buf.size == in_buf.pos && insz) { - if (++ni >= nrpages_in) { - erofs_err(sb, "invalid compressed data"); - err = -EFSCORRUPTED; - break; - } - - if (kout) /* unlike kmap(), take care of the orders */ - kunmap_local(kout); - kunmap_local(kin); - in_buf.size = min_t(u32, insz, PAGE_SIZE); - insz -= in_buf.size; - kin = kmap_local_page(rq->in[ni]); - in_buf.src = kin; - in_buf.pos = 0; - bounced = false; - if (kout) { - j = (u8 *)out_buf.dst - kout; - kout = kmap_local_page(rq->out[no]); - out_buf.dst = kout + j; - } } + in_buf.size = dctx.inbuf_sz; + in_buf.pos = dctx.inbuf_pos; - /* - * Handle overlapping: Use bounced buffer if the compressed - * data is under processing; Or use short-lived pages from the - * on-stack pagepool where pages share among the same request - * and not _all_ inplace I/O pages are needed to be doubled. - */ - if (!bounced && rq->out[no] == rq->in[ni]) { - memcpy(strm->bounce, in_buf.src, in_buf.size); - in_buf.src = strm->bounce; - bounced = true; - } - - for (j = ni + 1; j < nrpages_in; ++j) { - struct page *tmppage; - - if (rq->out[no] != rq->in[j]) - continue; - tmppage = erofs_allocpage(pgpl, rq->gfp); - if (!tmppage) { - err = -ENOMEM; - goto failed; - } - set_page_private(tmppage, Z_EROFS_SHORTLIVED_PAGE); - copy_highpage(tmppage, rq->in[j]); - rq->in[j] = tmppage; - } zerr = zstd_decompress_stream(stream, &out_buf, &in_buf); - if (zstd_is_error(zerr) || (!zerr && outsz)) { + if (zstd_is_error(zerr) || (!zerr && rq->outputsize)) { erofs_err(sb, "failed to decompress in[%u] out[%u]: %s", rq->inputsize, rq->outputsize, zerr ? zstd_get_error_name(zerr) : "unexpected end of stream"); err = -EFSCORRUPTED; break; } - } while (outsz || out_buf.pos < out_buf.size); -failed: - if (kout) - kunmap_local(kout); + } while (rq->outputsize || out_buf.pos < out_buf.size); + + if (dctx.kout) + kunmap_local(dctx.kout); failed_zinit: - kunmap_local(kin); + kunmap_local(dctx.kin); /* 4. push back ZSTD stream context to the global list */ spin_lock(&z_erofs_zstd_lock); strm->next = z_erofs_zstd_head; @@ -277,3 +215,11 @@ failed_zinit: wake_up(&z_erofs_zstd_wq); return err; } + +const struct z_erofs_decompressor z_erofs_zstd_decomp = { + .config = z_erofs_load_zstd_config, + .decompress = z_erofs_zstd_decompress, + .init = z_erofs_zstd_init, + .exit = z_erofs_zstd_exit, + .name = "zstd", +}; |