diff options
Diffstat (limited to 'drivers/staging/erofs/unzip_vle_lz4.c')
| -rw-r--r-- | drivers/staging/erofs/unzip_vle_lz4.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/staging/erofs/unzip_vle_lz4.c b/drivers/staging/erofs/unzip_vle_lz4.c new file mode 100644 index 000000000000..f5b665f15be5 --- /dev/null +++ b/drivers/staging/erofs/unzip_vle_lz4.c @@ -0,0 +1,209 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/drivers/staging/erofs/unzip_vle_lz4.c + * + * Copyright (C) 2018 HUAWEI, Inc. + * http://www.huawei.com/ + * Created by Gao Xiang <gaoxiang25@huawei.com> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of the Linux + * distribution for more details. + */ +#include "unzip_vle.h" + +#if Z_EROFS_CLUSTER_MAX_PAGES > Z_EROFS_VLE_INLINE_PAGEVECS +#define EROFS_PERCPU_NR_PAGES Z_EROFS_CLUSTER_MAX_PAGES +#else +#define EROFS_PERCPU_NR_PAGES Z_EROFS_VLE_INLINE_PAGEVECS +#endif + +static struct { + char data[PAGE_SIZE * EROFS_PERCPU_NR_PAGES]; +} erofs_pcpubuf[NR_CPUS]; + +int z_erofs_vle_plain_copy(struct page **compressed_pages, + unsigned clusterpages, + struct page **pages, + unsigned nr_pages, + unsigned short pageofs) +{ + unsigned i, j; + void *src = NULL; + const unsigned righthalf = PAGE_SIZE - pageofs; + char *percpu_data; + bool mirrored[Z_EROFS_CLUSTER_MAX_PAGES] = { 0 }; + + preempt_disable(); + percpu_data = erofs_pcpubuf[smp_processor_id()].data; + + j = 0; + for (i = 0; i < nr_pages; j = i++) { + struct page *page = pages[i]; + void *dst; + + if (page == NULL) { + if (src != NULL) { + if (!mirrored[j]) + kunmap_atomic(src); + src = NULL; + } + continue; + } + + dst = kmap_atomic(page); + + for (; j < clusterpages; ++j) { + if (compressed_pages[j] != page) + continue; + + BUG_ON(mirrored[j]); + memcpy(percpu_data + j * PAGE_SIZE, dst, PAGE_SIZE); + mirrored[j] = true; + break; + } + + if (i) { + if (src == NULL) + src = mirrored[i-1] ? + percpu_data + (i-1) * PAGE_SIZE : + kmap_atomic(compressed_pages[i-1]); + + memcpy(dst, src + righthalf, pageofs); + + if (!mirrored[i-1]) + kunmap_atomic(src); + + if (unlikely(i >= clusterpages)) { + kunmap_atomic(dst); + break; + } + } + + if (!righthalf) + src = NULL; + else { + src = mirrored[i] ? percpu_data + i * PAGE_SIZE : + kmap_atomic(compressed_pages[i]); + + memcpy(dst + pageofs, src, righthalf); + } + + kunmap_atomic(dst); + } + + if (src != NULL && !mirrored[j]) + kunmap_atomic(src); + + preempt_enable(); + return 0; +} + +extern int z_erofs_unzip_lz4(void *in, void *out, size_t inlen, size_t outlen); + +int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages, + unsigned clusterpages, + struct page **pages, + unsigned outlen, + unsigned short pageofs, + void (*endio)(struct page *)) +{ + void *vin, *vout; + unsigned nr_pages, i, j; + int ret; + + if (outlen + pageofs > EROFS_PERCPU_NR_PAGES * PAGE_SIZE) + return -ENOTSUPP; + + nr_pages = DIV_ROUND_UP(outlen + pageofs, PAGE_SIZE); + + if (clusterpages == 1) + vin = kmap_atomic(compressed_pages[0]); + else + vin = erofs_vmap(compressed_pages, clusterpages); + + preempt_disable(); + vout = erofs_pcpubuf[smp_processor_id()].data; + + ret = z_erofs_unzip_lz4(vin, vout + pageofs, + clusterpages * PAGE_SIZE, outlen); + + if (ret >= 0) { + outlen = ret; + ret = 0; + } + + for (i = 0; i < nr_pages; ++i) { + j = min((unsigned)PAGE_SIZE - pageofs, outlen); + + if (pages[i] != NULL) { + if (ret < 0) + SetPageError(pages[i]); + else if (clusterpages == 1 && pages[i] == compressed_pages[0]) + memcpy(vin + pageofs, vout + pageofs, j); + else { + void *dst = kmap_atomic(pages[i]); + + memcpy(dst + pageofs, vout + pageofs, j); + kunmap_atomic(dst); + } + endio(pages[i]); + } + vout += PAGE_SIZE; + outlen -= j; + pageofs = 0; + } + preempt_enable(); + + if (clusterpages == 1) + kunmap_atomic(vin); + else + erofs_vunmap(vin, clusterpages); + + return ret; +} + +int z_erofs_vle_unzip_vmap(struct page **compressed_pages, + unsigned clusterpages, + void *vout, + unsigned llen, + unsigned short pageofs, + bool overlapped) +{ + void *vin; + unsigned i; + int ret; + + if (overlapped) { + preempt_disable(); + vin = erofs_pcpubuf[smp_processor_id()].data; + + for (i = 0; i < clusterpages; ++i) { + void *t = kmap_atomic(compressed_pages[i]); + + memcpy(vin + PAGE_SIZE *i, t, PAGE_SIZE); + kunmap_atomic(t); + } + } else if (clusterpages == 1) + vin = kmap_atomic(compressed_pages[0]); + else { + vin = erofs_vmap(compressed_pages, clusterpages); + } + + ret = z_erofs_unzip_lz4(vin, vout + pageofs, + clusterpages * PAGE_SIZE, llen); + if (ret > 0) + ret = 0; + + if (!overlapped) { + if (clusterpages == 1) + kunmap_atomic(vin); + else { + erofs_vunmap(vin, clusterpages); + } + } else + preempt_enable(); + + return ret; +} + |