From 84f394e9c0cd9a82948f0027a76c8b41b14a11bc Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Tue, 26 May 2020 16:16:42 -0600 Subject: lib/cbfs: add cbfs_stage_load_and_decompress helper The LZ4 compressed stages assume in-place decompression. The constraints are validated in cbfstool for _stages_ such that they can be decompressed in place. However, that is only true for stages. As such, add a wrapper, cbfs_stage_load_and_decompress(), that handles the LZ4 stage loading case. BUG=b:155322763,b:150746858,b:152909132 Change-Id: I9525a266250aa6c775283b598c09d4f40692db55 Signed-off-by: Aaron Durbin Reviewed-on: https://review.coreboot.org/c/coreboot/+/41755 Reviewed-by: Arthur Heymans Reviewed-by: Furquan Shaikh Reviewed-by: Julius Werner Tested-by: build bot (Jenkins) --- src/lib/cbfs.c | 49 ++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 40 insertions(+), 9 deletions(-) (limited to 'src') diff --git a/src/lib/cbfs.c b/src/lib/cbfs.c index 74df3c5b39..e05ea801c8 100644 --- a/src/lib/cbfs.c +++ b/src/lib/cbfs.c @@ -116,6 +116,7 @@ size_t cbfs_load_and_decompress(const struct region_device *rdev, size_t offset, size_t in_size, void *buffer, size_t buffer_size, uint32_t compression) { size_t out_size; + void *map; switch (compression) { case CBFS_COMPRESS_NONE: @@ -129,23 +130,24 @@ size_t cbfs_load_and_decompress(const struct region_device *rdev, size_t offset, if (!cbfs_lz4_enabled()) return 0; - /* Load the compressed image to the end of the available memory - * area for in-place decompression. It is the responsibility of - * the caller to ensure that buffer_size is large enough - * (see compression.h, guaranteed by cbfstool for stages). */ - void *compr_start = buffer + buffer_size - in_size; - if (rdev_readat(rdev, compr_start, offset, in_size) != in_size) + /* cbfs_stage_load_and_decompress() takes care of in-place + lz4 decompression by setting up the rdev to be in memory. */ + map = rdev_mmap(rdev, offset, in_size); + if (map == NULL) return 0; timestamp_add_now(TS_START_ULZ4F); - out_size = ulz4fn(compr_start, in_size, buffer, buffer_size); + out_size = ulz4fn(map, in_size, buffer, buffer_size); timestamp_add_now(TS_END_ULZ4F); + + rdev_munmap(rdev, map); + return out_size; case CBFS_COMPRESS_LZMA: if (!cbfs_lzma_enabled()) return 0; - void *map = rdev_mmap(rdev, offset, in_size); + map = rdev_mmap(rdev, offset, in_size); if (map == NULL) return 0; @@ -163,6 +165,35 @@ size_t cbfs_load_and_decompress(const struct region_device *rdev, size_t offset, } } +static size_t cbfs_stage_load_and_decompress(const struct region_device *rdev, + size_t offset, size_t in_size, void *buffer, size_t buffer_size, + uint32_t compression) +{ + struct region_device rdev_src; + + if (compression == CBFS_COMPRESS_LZ4) { + if (!cbfs_lz4_enabled()) + return 0; + /* Load the compressed image to the end of the available memory + * area for in-place decompression. It is the responsibility of + * the caller to ensure that buffer_size is large enough + * (see compression.h, guaranteed by cbfstool for stages). */ + void *compr_start = buffer + buffer_size - in_size; + if (rdev_readat(rdev, compr_start, offset, in_size) != in_size) + return 0; + /* Create a region device backed by memory. */ + rdev_chain(&rdev_src, &addrspace_32bit.rdev, + (uintptr_t)compr_start, in_size); + + return cbfs_load_and_decompress(&rdev_src, 0, in_size, buffer, + buffer_size, compression); + } + + /* All other algorithms can use the generic implementation. */ + return cbfs_load_and_decompress(rdev, offset, in_size, buffer, + buffer_size, compression); +} + static inline int tohex4(unsigned int c) { return (c <= 9) ? (c + '0') : (c - 10 + 'a'); @@ -257,7 +288,7 @@ int cbfs_prog_stage_load(struct prog *pstage) goto out; } - fsize = cbfs_load_and_decompress(fh, foffset, fsize, load, + fsize = cbfs_stage_load_and_decompress(fh, foffset, fsize, load, stage.memlen, stage.compression); if (!fsize) return -1; -- cgit v1.2.3