/* * Copyright (c) 2013, 2014 * Phillip Lougher * * This work is licensed under the terms of the GNU GPL, version 2. See * the COPYING file in the top-level directory. */ #include #include #include #include #include #include "squashfs_fs.h" #include "squashfs_fs_sb.h" #include "squashfs.h" #include "decompressor.h" #include "page_actor.h" #define LZ4_LEGACY 1 struct lz4_comp_opts { __le32 version; __le32 flags; }; struct squashfs_lz4 { void *input; void *output; }; static void *lz4_comp_opts(struct squashfs_sb_info *msblk, void *buff, int len) { struct lz4_comp_opts *comp_opts = buff; /* LZ4 compressed filesystems always have compression options */ if (comp_opts == NULL || len < sizeof(*comp_opts)) return ERR_PTR(-EIO); if (le32_to_cpu(comp_opts->version) != LZ4_LEGACY) { /* LZ4 format currently used by the kernel is the 'legacy' * format */ ERROR("Unknown LZ4 version\n"); return ERR_PTR(-EINVAL); } return NULL; } static void *lz4_init(struct squashfs_sb_info *msblk, void *buff) { int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE); struct squashfs_lz4 *stream; stream = kzalloc(sizeof(*stream), GFP_KERNEL); if (stream == NULL) goto failed; stream->input = vmalloc(block_size); if (stream->input == NULL) goto failed2; stream->output = vmalloc(block_size); if (stream->output == NULL) goto failed3; return stream; failed3: vfree(stream->input); failed2: kfree(stream); failed: ERROR("Failed to initialise LZ4 decompressor\n"); return ERR_PTR(-ENOMEM); } static void lz4_free(void *strm) { struct squashfs_lz4 *stream = strm; if (stream) { vfree(stream->input); vfree(stream->output); } kfree(stream); } static int lz4_uncompress(struct squashfs_sb_info *msblk, void *strm, struct buffer_head **bh, int b, int offset, int length, struct squashfs_page_actor *output) { struct squashfs_lz4 *stream = strm; void *buff = stream->input, *data; int avail, i, bytes = length, res; size_t dest_len = output->length; for (i = 0; i < b; i++) { avail = min(bytes, msblk->devblksize - offset); memcpy(buff, bh[i]->b_data + offset, avail); buff += avail; bytes -= avail; offset = 0; put_bh(bh[i]); } res = lz4_decompress_unknownoutputsize(stream->input, length, stream->output, &dest_len); if (res) return -EIO; bytes = dest_len; data = squashfs_first_page(output); buff = stream->output; while (data) { if (bytes <= PAGE_SIZE) { memcpy(data, buff, bytes); break; } memcpy(data, buff, PAGE_SIZE); buff += PAGE_SIZE; bytes -= PAGE_SIZE; data = squashfs_next_page(output); } squashfs_finish_page(output); return dest_len; } const struct squashfs_decompressor squashfs_lz4_comp_ops = { .init = lz4_init, .comp_opts = lz4_comp_opts, .free = lz4_free, .decompress = lz4_uncompress, .id = LZ4_COMPRESSION, .name = "lz4", .supported = 1 }; class='ctrl'>space:mode:
authorJie Chen <fykcee1@gmail.com>2016-12-12 16:46:17 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 18:55:09 -0800
commitce093a04543c403d52c1a5788d8cb92e47453aba (patch)
tree4f0dbd7ab08c3110cc45f2ce94662ea3e561c00c /include
parent6b2a65c7ff612035deb1012388738b54e08ab2a6 (diff)
lib/rbtree.c: fix typo in comment of ____rb_erase_color
In Case 3 of `sibling == parent->rb_right': Right rotation will not change color of sl and S in the diagram (i.e. should not change "sl" to "Sl", "S" to "s") In Case 3 of `sibling == parent->rb_left': (p) (p) / \ / \ S N --> sr N / \ / Sl sr S / Sl This is actually left rotation at "S", not right rotation. In Case 4 of `sibling == parent->rb_left': (p) (s) / \ / \ S N --> Sl P / \ / \ sl (sr) (sr) N This is actually right rotation at "(p)" + color flips, not left rotation + color flips. Link: http://lkml.kernel.org/r/1472391115-3702-1-git-send-email-fykcee1@gmail.com Signed-off-by: Jie Chen <fykcee1@gmail.com> Cc: Wei Yang <weiyang@linux.vnet.ibm.com> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')