Add erofs_rebuild_load_tree() helper loading inode tree from given erofs image, and making it merged into a given inode tree in an overlayfs like model.
Since we need to read the content of the symlink file from disk when loading tree, add dependency on zlib_LIBS for mkfs.erofs. Also rename tarerofs_dump_tree() to erofs_rebuild_dump_tree(), so that it could also be called from rebuild mode. Signed-off-by: Jingbo Xu <[email protected]> --- include/erofs/inode.h | 2 +- include/erofs/internal.h | 1 + include/erofs/rebuild.h | 2 + lib/inode.c | 4 +- lib/rebuild.c | 283 +++++++++++++++++++++++++++++++++++++++ mkfs/main.c | 2 +- 6 files changed, 290 insertions(+), 4 deletions(-) diff --git a/include/erofs/inode.h b/include/erofs/inode.h index 1c602a8..fe9dda2 100644 --- a/include/erofs/inode.h +++ b/include/erofs/inode.h @@ -32,7 +32,7 @@ unsigned int erofs_iput(struct erofs_inode *inode); erofs_nid_t erofs_lookupnid(struct erofs_inode *inode); struct erofs_dentry *erofs_d_alloc(struct erofs_inode *parent, const char *name); -int tarerofs_dump_tree(struct erofs_inode *dir); +int erofs_rebuild_dump_tree(struct erofs_inode *dir); int erofs_init_empty_dir(struct erofs_inode *dir); struct erofs_inode *erofs_new_inode(void); struct erofs_inode *erofs_mkfs_build_tree_from_path(const char *path); diff --git a/include/erofs/internal.h b/include/erofs/internal.h index 6020553..3d5c337 100644 --- a/include/erofs/internal.h +++ b/include/erofs/internal.h @@ -108,6 +108,7 @@ struct erofs_sb_info { int devfd; u64 devsz; + dev_t dev; unsigned int nblobs; unsigned int blobfd[256]; }; diff --git a/include/erofs/rebuild.h b/include/erofs/rebuild.h index 92873c9..3ac074c 100644 --- a/include/erofs/rebuild.h +++ b/include/erofs/rebuild.h @@ -12,6 +12,8 @@ extern "C" struct erofs_dentry *erofs_rebuild_get_dentry(struct erofs_inode *pwd, char *path, bool aufs, bool *whout, bool *opq); +int erofs_rebuild_load_tree(struct erofs_inode *root, struct erofs_sb_info *sbi); + #ifdef __cplusplus } #endif diff --git a/lib/inode.c b/lib/inode.c index cd51fd2..f71a6ab 100644 --- a/lib/inode.c +++ b/lib/inode.c @@ -1323,7 +1323,7 @@ struct erofs_inode *erofs_mkfs_build_special_from_fd(int fd, const char *name) return inode; } -int tarerofs_dump_tree(struct erofs_inode *dir) +int erofs_rebuild_dump_tree(struct erofs_inode *dir) { struct erofs_dentry *d; unsigned int nr_subdirs; @@ -1391,7 +1391,7 @@ int tarerofs_dump_tree(struct erofs_inode *dir) continue; inode = erofs_igrab(d->inode); - ret = tarerofs_dump_tree(inode); + ret = erofs_rebuild_dump_tree(inode); dir->i_nlink += (erofs_mode_to_ftype(inode->i_mode) == EROFS_FT_DIR); erofs_iput(inode); if (ret) diff --git a/lib/rebuild.c b/lib/rebuild.c index 7aaa071..6e5ae29 100644 --- a/lib/rebuild.c +++ b/lib/rebuild.c @@ -3,9 +3,18 @@ #include <unistd.h> #include <stdlib.h> #include <string.h> +#include <sys/stat.h> +#include <config.h> +#if defined(HAVE_SYS_SYSMACROS_H) +#include <sys/sysmacros.h> +#endif #include "erofs/print.h" #include "erofs/inode.h" #include "erofs/rebuild.h" +#include "erofs/io.h" +#include "erofs/dir.h" +#include "erofs/xattr.h" +#include "erofs/blobchunk.h" #include "erofs/internal.h" #ifdef HAVE_LINUX_AUFS_TYPE_H @@ -115,3 +124,277 @@ struct erofs_dentry *erofs_rebuild_get_dentry(struct erofs_inode *pwd, } return d; } + +static int erofs_rebuild_fixup_inode_index(struct erofs_inode *inode) +{ + int ret; + unsigned int count, unit, chunkbits, i; + unsigned int deviceid = inode->dev; + struct erofs_inode_chunk_index *idx; + erofs_off_t chunksize; + erofs_blk_t blkaddr; + + /* TODO: fill data map in other layouts */ + if (inode->datalayout != EROFS_INODE_CHUNK_BASED && + inode->datalayout != EROFS_INODE_FLAT_PLAIN) { + erofs_err("unsupported datalayout %d", inode->datalayout); + return -EOPNOTSUPP; + } + + if (inode->sbi->extra_devices) { + chunkbits = inode->u.chunkbits; + if (chunkbits < sbi.blkszbits) { + erofs_err("blkszbits no greater than source blkszbits"); + return -EINVAL; + } + } else { + chunkbits = ilog2(inode->i_size - 1) + 1; + if (chunkbits < sbi.blkszbits) + chunkbits = sbi.blkszbits; + if (chunkbits - sbi.blkszbits > EROFS_CHUNK_FORMAT_BLKBITS_MASK) + chunkbits = EROFS_CHUNK_FORMAT_BLKBITS_MASK + sbi.blkszbits; + } + chunksize = 1ULL << chunkbits; + count = DIV_ROUND_UP(inode->i_size, chunksize); + + unit = sizeof(struct erofs_inode_chunk_index); + inode->extent_isize = count * unit; + idx = malloc(max(sizeof(*idx), sizeof(void *))); + if (!idx) + return -ENOMEM; + inode->chunkindexes = idx; + + for (i = 0; i < count; i++) { + struct erofs_blobchunk *chunk; + struct erofs_map_blocks map = { + .index = UINT_MAX, + }; + + map.m_la = i << chunkbits; + ret = erofs_map_blocks(inode, &map, 0); + if (ret) + goto err; + + blkaddr = erofs_blknr(&sbi, map.m_pa); + chunk = erofs_get_unhashed_chunk(deviceid, blkaddr, 0); + if (IS_ERR(chunk)) { + ret = PTR_ERR(chunk); + goto err; + } + *(void **)idx++ = chunk; + + } + inode->datalayout = EROFS_INODE_CHUNK_BASED; + inode->u.chunkformat = EROFS_CHUNK_FORMAT_INDEXES; + inode->u.chunkformat |= chunkbits - sbi.blkszbits; + return 0; +err: + free(idx); + inode->chunkindexes = NULL; + return ret; +} + +static int erofs_rebuild_fill_inode(struct erofs_inode *inode) +{ + int ret = 0; + + switch (inode->i_mode & S_IFMT) { + case S_IFCHR: + case S_IFBLK: + case S_IFIFO: + case S_IFSOCK: + inode->i_size = 0; + erofs_dbg("\tdev: %d %d", major(inode->u.i_rdev), + minor(inode->u.i_rdev)); + inode->u.i_rdev = erofs_new_encode_dev(inode->u.i_rdev); + break; + case S_IFDIR: + ret = erofs_init_empty_dir(inode); + break; + case S_IFLNK: + inode->i_link = malloc(inode->i_size + 1); + if (!inode->i_link) + return -ENOMEM; + ret = erofs_pread(inode, inode->i_link, inode->i_size, 0); + erofs_dbg("\tsymlink: %s -> %s", inode->i_srcpath, inode->i_link); + break; + case S_IFREG: + if (inode->i_size) + ret = erofs_rebuild_fixup_inode_index(inode); + break; + default: + ret = -EINVAL; + break; + } + return ret; +} + +/* + * @parent: parent directory in inode tree + * @ctx.dir: parent directory when itering erofs_iterate_dir() + */ +struct erofs_rebuild_dir_context { + struct erofs_dir_context ctx; + struct erofs_inode *parent; + dev_t dev; +}; + +static int erofs_rebuild_dirent_iter(struct erofs_dir_context *ctx) +{ + struct erofs_rebuild_dir_context *rctx = (void *)ctx; + struct erofs_inode *parent = rctx->parent; + struct erofs_inode *dir = ctx->dir; + struct erofs_inode *inode, *candidate; + struct erofs_inode src; + struct erofs_dentry *d; + char *path, *dname; + int ret; + + if (ctx->dot_dotdot) + return 0; + + ret = asprintf(&path, "%s/%.*s", rctx->parent->i_srcpath, + ctx->de_namelen, ctx->dname); + if (ret < 0) + return ret; + + erofs_dbg("parsing path %s", path); + dname = path + strlen(parent->i_srcpath) + 1; + + d = erofs_rebuild_get_dentry(parent, dname, false, NULL, NULL); + if (IS_ERR(d)) { + ret = PTR_ERR(d); + goto out; + } + DBG_BUGON(parent != d->inode); + + ret = 0; + if (d->type != EROFS_FT_UNKNOWN) { + /* file exists in upper layer */ + if (!S_ISDIR(d->inode->i_mode) || d->inode->opaque) + goto out; + + /* merging directories */ + src = (struct erofs_inode) { + .sbi = dir->sbi, + .nid = ctx->de_nid + }; + ret = erofs_read_inode_from_disk(&src); + if (ret || !S_ISDIR(src.i_mode)) + goto out; + parent = d->inode; + inode = dir = &src; + } else { + u64 nid; + + inode = erofs_new_inode(); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto out; + } + + /* reuse i_ino[0] to read nid in source fs */ + nid = inode->i_ino[0]; + inode->sbi = dir->sbi; + inode->nid = ctx->de_nid; + ret = erofs_read_inode_from_disk(inode); + if (ret) + goto out; + + /* restore nid in new generated fs */ + inode->i_ino[1] = inode->i_ino[0]; + inode->i_ino[0] = nid; + + if (S_ISREG(inode->i_mode) && inode->i_nlink > 1 && + (candidate = erofs_iget(rctx->dev, ctx->de_nid))) { + /* hardlink file */ + erofs_iput(inode); + inode = candidate; + if (S_ISDIR(inode->i_mode)) { + erofs_err("hardlink directory not supported"); + ret = -EISDIR; + goto out; + } + inode->i_nlink++; + erofs_dbg("\thardlink: %s -> %s", path, inode->i_srcpath); + } else { + ret = erofs_read_xattrs_from_disk(inode); + if (ret) { + erofs_iput(inode); + goto out; + } + + inode->i_parent = d->inode; + inode->dev = rctx->dev; + inode->i_srcpath = path; + path = NULL; + inode->i_ino[1] = inode->nid; + inode->i_nlink = 1; + + ret = erofs_rebuild_fill_inode(inode); + if (ret) { + erofs_iput(inode); + goto out; + } + + erofs_insert_ihash(inode, rctx->dev, inode->i_ino[1]); + parent = dir = inode; + } + + d->inode = inode; + d->type = erofs_mode_to_ftype(inode->i_mode); + } + + ret = 0; + if (S_ISDIR(inode->i_mode)) { + struct erofs_rebuild_dir_context nctx = *rctx; + nctx.parent = parent; + nctx.ctx.dir = dir; + ret = erofs_iterate_dir(&nctx.ctx, false); + } + + /* don't restore inode->sbi until all the read work has finished */ + inode->sbi = &sbi; + inode->nid = 0; +out: + if (path) + free(path); + return ret; +} + +int erofs_rebuild_load_tree(struct erofs_inode *root, struct erofs_sb_info *sbi) +{ + struct erofs_inode inode = {}; + struct erofs_rebuild_dir_context ctx; + int ret; + + if (!sbi->devname) { + erofs_err("failed to find a device for rebuilding"); + return -EINVAL; + } + + ret = erofs_read_superblock(sbi); + if (ret) { + erofs_err("failed to read superblock of %s", sbi->devname); + return ret; + } + + inode.nid = sbi->root_nid; + inode.sbi = sbi; + ret = erofs_read_inode_from_disk(&inode); + if (ret) { + erofs_err("failed to read root inode of %s", sbi->devname); + return ret; + } + inode.i_srcpath = strdup("/"); + + ctx = (struct erofs_rebuild_dir_context) { + .ctx.dir = &inode, + .ctx.cb = erofs_rebuild_dirent_iter, + .parent = root, + .dev = sbi->dev, + }; + ret = erofs_iterate_dir(&ctx.ctx, false); + free(inode.i_srcpath); + return ret; +} diff --git a/mkfs/main.c b/mkfs/main.c index 4352e62..0333cde 100644 --- a/mkfs/main.c +++ b/mkfs/main.c @@ -965,7 +965,7 @@ int main(int argc, char **argv) if (err < 0) goto exit; - err = tarerofs_dump_tree(root_inode); + err = erofs_rebuild_dump_tree(root_inode); if (err < 0) goto exit; } -- 2.19.1.6.gb485710b
