X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lib%2Fext2fs%2Fopenfs.c;h=35bd44bc0ca122110225f6d8848edb34d7ff7e8a;hb=2628a1d3e1e581512d136486768685542d2649b1;hp=07f47a5687a364e8e0dcff1fbfa53add8317e799;hpb=c555aebde40afdc0d15d674f2c81c0e05cfded3f;p=tools%2Fe2fsprogs.git diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c index 07f47a5..35bd44b 100644 --- a/lib/ext2fs/openfs.c +++ b/lib/ext2fs/openfs.c @@ -14,9 +14,6 @@ #if HAVE_UNISTD_H #include #endif -#if HAVE_STDLIB_H -#include -#endif #include #include #if HAVE_SYS_STAT_H @@ -26,9 +23,49 @@ #include #endif -#include +#include "ext2_fs.h" + #include "ext2fs.h" +#include "e2image.h" + +blk_t ext2fs_descriptor_block_loc(ext2_filsys fs, blk_t group_block, dgrp_t i) +{ + int bg; + int has_super = 0; + int ret_blk; + + if (!(fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) || + (i < fs->super->s_first_meta_bg)) + return (group_block + i + 1); + + bg = (fs->blocksize / sizeof (struct ext2_group_desc)) * i; + if (ext2fs_bg_has_super(fs, bg)) + has_super = 1; + ret_blk = (fs->super->s_first_data_block + has_super + + (bg * fs->super->s_blocks_per_group)); + /* + * If group_block is not the normal value, we're trying to use + * the backup group descriptors and superblock --- so use the + * alternate location of the second block group in the + * metablock group. Ideally we should be testing each bg + * descriptor block individually for correctness, but we don't + * have the infrastructure in place to do that. + */ + if (group_block != fs->super->s_first_data_block && + ((ret_blk + fs->super->s_blocks_per_group) < + fs->super->s_blocks_count)) + ret_blk += fs->super->s_blocks_per_group; + return ret_blk; +} + +errcode_t ext2fs_open(const char *name, int flags, int superblock, + unsigned int block_size, io_manager manager, + ext2_filsys *ret_fs) +{ + return ext2fs_open2(name, 0, flags, superblock, block_size, + manager, ret_fs); +} /* * Note: if superblock is non-zero, block-size must also be non-zero. @@ -38,43 +75,75 @@ * * EXT2_FLAG_RW - Open the filesystem for read/write. * EXT2_FLAG_FORCE - Open the filesystem even if some of the - * features aren't supported. + * features aren't supported. + * EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device */ -errcode_t ext2fs_open(const char *name, int flags, int superblock, - int block_size, io_manager manager, ext2_filsys *ret_fs) +errcode_t ext2fs_open2(const char *name, const char *io_options, + int flags, int superblock, + unsigned int block_size, io_manager manager, + ext2_filsys *ret_fs) { ext2_filsys fs; errcode_t retval; - int i, j, groups_per_block; - blk_t group_block; - char *dest; + unsigned long i; + __u32 features; + int j, groups_per_block, blocks_per_group, io_flags; + blk_t group_block, blk; + char *dest, *cp; struct ext2_group_desc *gdp; - struct ext2fs_sb *s; EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER); - - fs = (ext2_filsys) malloc(sizeof(struct struct_ext2_filsys)); - if (!fs) - return EXT2_NO_MEMORY; + + retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs); + if (retval) + return retval; memset(fs, 0, sizeof(struct struct_ext2_filsys)); fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS; fs->flags = flags; - retval = manager->open(name, (flags & EXT2_FLAG_RW) ? IO_FLAG_RW : 0, - &fs->io); + /* don't overwrite sb backups unless flag is explicitly cleared */ + fs->flags |= EXT2_FLAG_MASTER_SB_ONLY; + fs->umask = 022; + retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name); if (retval) goto cleanup; - fs->io->app_data = fs; - fs->device_name = malloc(strlen(name)+1); - if (!fs->device_name) { - retval = EXT2_NO_MEMORY; - goto cleanup; - } strcpy(fs->device_name, name); - fs->super = malloc(SUPERBLOCK_SIZE); - if (!fs->super) { - retval = EXT2_NO_MEMORY; + cp = strchr(fs->device_name, '?'); + if (!io_options && cp) { + *cp++ = 0; + io_options = cp; + } + + io_flags = 0; + if (flags & EXT2_FLAG_RW) + io_flags |= IO_FLAG_RW; + if (flags & EXT2_FLAG_EXCLUSIVE) + io_flags |= IO_FLAG_EXCLUSIVE; + retval = manager->open(fs->device_name, io_flags, &fs->io); + if (retval) + goto cleanup; + if (io_options && + (retval = io_channel_set_options(fs->io, io_options))) + goto cleanup; + fs->image_io = fs->io; + fs->io->app_data = fs; + retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->super); + if (retval) goto cleanup; + if (flags & EXT2_FLAG_IMAGE_FILE) { + retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr), + &fs->image_header); + if (retval) + goto cleanup; + retval = io_channel_read_blk(fs->io, 0, + -(int)sizeof(struct ext2_image_hdr), + fs->image_header); + if (retval) + goto cleanup; + if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE) + return EXT2_ET_MAGIC_E2IMAGE; + superblock = 1; + block_size = fs->image_header->fs_blocksize; } /* @@ -82,63 +151,83 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock, * superblock, then he/she must also specify the block size! * Otherwise, read the master superblock located at offset * SUPERBLOCK_OFFSET from the start of the partition. + * + * Note: we only save a backup copy of the superblock if we + * are reading the superblock from the primary superblock location. */ if (superblock) { if (!block_size) { - retval = EXT2_INVALID_ARGUMENT; + retval = EXT2_ET_INVALID_ARGUMENT; goto cleanup; } io_channel_set_blksize(fs->io, block_size); - group_block = superblock + 1; + group_block = superblock; + fs->orig_super = 0; } else { io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET); superblock = 1; group_block = 0; + retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super); + if (retval) + goto cleanup; } retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE, fs->super); if (retval) goto cleanup; + if (fs->orig_super) + memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE); - if ((fs->super->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC)) || - (fs->flags & EXT2_FLAG_SWAP_BYTES)) { - fs->flags |= EXT2_FLAG_SWAP_BYTES; - - ext2fs_swap_super(fs->super); +#ifdef WORDS_BIGENDIAN + fs->flags |= EXT2_FLAG_SWAP_BYTES; + ext2fs_swap_super(fs->super); +#else + if (fs->flags & EXT2_FLAG_SWAP_BYTES) { + retval = EXT2_ET_UNIMPLEMENTED; + goto cleanup; } +#endif if (fs->super->s_magic != EXT2_SUPER_MAGIC) { retval = EXT2_ET_BAD_MAGIC; goto cleanup; } -#ifdef EXT2_DYNAMIC_REV - if (fs->super->s_rev_level > EXT2_DYNAMIC_REV) { - retval = EXT2_ET_REV_TOO_HIGH; - goto cleanup; - } -#else -#ifdef EXT2_CURRENT_REV if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) { retval = EXT2_ET_REV_TOO_HIGH; goto cleanup; } -#endif -#endif + /* * Check for feature set incompatibility */ if (!(flags & EXT2_FLAG_FORCE)) { - s = (struct ext2fs_sb *) fs->super; - if (s->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) { + features = fs->super->s_feature_incompat; +#ifdef EXT2_LIB_SOFTSUPP_INCOMPAT + if (flags & EXT2_FLAG_SOFTSUPP_FEATURES) + features &= !EXT2_LIB_SOFTSUPP_INCOMPAT; +#endif + if (features & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) { retval = EXT2_ET_UNSUPP_FEATURE; goto cleanup; } + + features = fs->super->s_feature_ro_compat; +#ifdef EXT2_LIB_SOFTSUPP_RO_COMPAT + if (flags & EXT2_FLAG_SOFTSUPP_FEATURES) + features &= !EXT2_LIB_SOFTSUPP_RO_COMPAT; +#endif if ((flags & EXT2_FLAG_RW) && - (s->s_feature_ro_compat & - ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) { + (features & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) { retval = EXT2_ET_RO_UNSUPP_FEATURE; goto cleanup; } + + if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) && + (fs->super->s_feature_incompat & + EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) { + retval = EXT2_ET_UNSUPP_FEATURE; + goto cleanup; + } } fs->blocksize = EXT2_BLOCK_SIZE(fs->super); @@ -146,6 +235,10 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock, retval = EXT2_ET_CORRUPT_SUPERBLOCK; goto cleanup; } + if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) { + retval = EXT2_ET_CORRUPT_SUPERBLOCK; + goto cleanup; + } fs->fragsize = EXT2_FRAG_SIZE(fs->super); fs->inode_blocks_per_group = ((fs->super->s_inodes_per_group * EXT2_INODE_SIZE(fs->super) + @@ -161,40 +254,56 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock, * Set the blocksize to the filesystem's blocksize. */ io_channel_set_blksize(fs->io, fs->blocksize); + + /* + * If this is an external journal device, don't try to read + * the group descriptors, because they're not there. + */ + if (fs->super->s_feature_incompat & + EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) { + fs->group_desc_count = 0; + *ret_fs = fs; + return 0; + } /* * Read group descriptors */ - fs->group_desc_count = (fs->super->s_blocks_count - - fs->super->s_first_data_block + - EXT2_BLOCKS_PER_GROUP(fs->super) - 1) - / EXT2_BLOCKS_PER_GROUP(fs->super); - fs->desc_blocks = (fs->group_desc_count + - EXT2_DESC_PER_BLOCK(fs->super) - 1) - / EXT2_DESC_PER_BLOCK(fs->super); - fs->group_desc = malloc((size_t) (fs->desc_blocks * fs->blocksize)); - if (!fs->group_desc) { - retval = EXT2_NO_MEMORY; + blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super); + if (blocks_per_group == 0 || + blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) || + fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super)) { + retval = EXT2_ET_CORRUPT_SUPERBLOCK; goto cleanup; } + fs->group_desc_count = ext2fs_div_ceil(fs->super->s_blocks_count - + fs->super->s_first_data_block, + blocks_per_group); + fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count, + EXT2_DESC_PER_BLOCK(fs->super)); + retval = ext2fs_get_mem(fs->desc_blocks * fs->blocksize, + &fs->group_desc); + if (retval) + goto cleanup; if (!group_block) - group_block = fs->super->s_first_data_block + 1; + group_block = fs->super->s_first_data_block; dest = (char *) fs->group_desc; + groups_per_block = fs->blocksize / sizeof(struct ext2_group_desc); for (i=0 ; i < fs->desc_blocks; i++) { - retval = io_channel_read_blk(fs->io, group_block, 1, dest); + blk = ext2fs_descriptor_block_loc(fs, group_block, i); + retval = io_channel_read_blk(fs->io, blk, 1, dest); if (retval) goto cleanup; - group_block++; - if (fs->flags & EXT2_FLAG_SWAP_BYTES) { - gdp = (struct ext2_group_desc *) dest; - groups_per_block = fs->blocksize / - sizeof(struct ext2_group_desc); - for (j=0; j < groups_per_block; j++) - ext2fs_swap_group_desc(gdp++); - } +#ifdef WORDS_BIGENDIAN + gdp = (struct ext2_group_desc *) dest; + for (j=0; j < groups_per_block; j++) + ext2fs_swap_group_desc(gdp++); +#endif dest += fs->blocksize; } + fs->stride = fs->super->s_raid_stride; + *ret_fs = fs; return 0; cleanup: @@ -202,3 +311,36 @@ cleanup: return retval; } +/* + * Set/get the filesystem data I/O channel. + * + * These functions are only valid if EXT2_FLAG_IMAGE_FILE is true. + */ +errcode_t ext2fs_get_data_io(ext2_filsys fs, io_channel *old_io) +{ + if ((fs->flags & EXT2_FLAG_IMAGE_FILE) == 0) + return EXT2_ET_NOT_IMAGE_FILE; + if (old_io) { + *old_io = (fs->image_io == fs->io) ? 0 : fs->io; + } + return 0; +} + +errcode_t ext2fs_set_data_io(ext2_filsys fs, io_channel new_io) +{ + if ((fs->flags & EXT2_FLAG_IMAGE_FILE) == 0) + return EXT2_ET_NOT_IMAGE_FILE; + fs->io = new_io ? new_io : fs->image_io; + return 0; +} + +errcode_t ext2fs_rewrite_to_io(ext2_filsys fs, io_channel new_io) +{ + if ((fs->flags & EXT2_FLAG_IMAGE_FILE) == 0) + return EXT2_ET_NOT_IMAGE_FILE; + fs->io = fs->image_io = new_io; + fs->flags |= EXT2_FLAG_DIRTY | EXT2_FLAG_RW | + EXT2_FLAG_BB_DIRTY | EXT2_FLAG_IB_DIRTY; + fs->flags &= ~EXT2_FLAG_IMAGE_FILE; + return 0; +}