X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/a7384053efe345d199440720b437a28e91058ff3..28c176b668c841a3b7fb093faccf0efa39257603:/lunaix-os/kernel/fs/vfs.c diff --git a/lunaix-os/kernel/fs/vfs.c b/lunaix-os/kernel/fs/vfs.c index b879185..d4bc56a 100644 --- a/lunaix-os/kernel/fs/vfs.c +++ b/lunaix-os/kernel/fs/vfs.c @@ -40,37 +40,22 @@ we can do similar thing in Lunaix? A block device emulation above the regular file when we mount it on. 10. (device) device number (dev_t) allocation - [good idea] :: composition + [good idea] :: composition (CHECKED) */ #include -#include #include #include #include -#include #include #include #include #include +#include #include -#define PATH_DELIM '/' - -#define unlock_inode(inode) mutex_unlock(&inode->lock) -#define lock_inode(inode) \ - ({ \ - mutex_lock(&inode->lock); \ - lru_use_one(inode_lru, &inode->lru); \ - }) - -#define unlock_dnode(dnode) mutex_unlock(&dnode->lock) -#define lock_dnode(dnode) \ - ({ \ - mutex_lock(&dnode->lock); \ - lru_use_one(dnode_lru, &dnode->lru); \ - }) +#include static struct cake_pile* dnode_pile; static struct cake_pile* inode_pile; @@ -81,7 +66,7 @@ static struct cake_pile* fd_pile; struct v_dnode* vfs_sysroot; static struct hbucket* dnode_cache; -static struct lru_zone *dnode_lru, *inode_lru; +struct lru_zone *dnode_lru, *inode_lru; struct hstr vfs_ddot = HSTR("..", 2); struct hstr vfs_dot = HSTR(".", 1); @@ -120,17 +105,18 @@ vfs_init() // 创建一个根dnode。 vfs_sysroot = vfs_d_alloc(NULL, &vfs_empty); + vfs_sysroot->parent = vfs_sysroot; atomic_fetch_add(&vfs_sysroot->ref_count, 1); } -inline struct hbucket* -__dcache_hash(struct v_dnode* parent, uint32_t* hash) +static inline struct hbucket* +__dcache_hash(struct v_dnode* parent, u32_t* hash) { - uint32_t _hash = *hash; - // 与parent的指针值做加法，来减小碰撞的可能性。 - _hash += (uint32_t)parent; + u32_t _hash = *hash; // 确保低位更加随机 _hash = _hash ^ (_hash >> VFS_HASHBITS); + // 与parent的指针值做加法，来减小碰撞的可能性。 + _hash += (u32_t)__ptr(parent); *hash = _hash; return &dnode_cache[_hash & VFS_HASH_MASK]; } @@ -142,10 +128,10 @@ vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str) return parent; if (HSTR_EQ(str, &vfs_ddot)) { - return parent->parent ? parent->parent : parent; + return parent->parent; } - uint32_t hash = str->hash; + u32_t hash = str->hash; struct hbucket* slot = __dcache_hash(parent, &hash); struct v_dnode *pos, *n; @@ -161,6 +147,8 @@ vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str) void vfs_dcache_add(struct v_dnode* parent, struct v_dnode* dnode) { + assert(parent); + atomic_fetch_add(&dnode->ref_count, 1); dnode->parent = parent; llist_append(&parent->children, &dnode->siblings); @@ -172,9 +160,11 @@ vfs_dcache_add(struct v_dnode* parent, struct v_dnode* dnode) void vfs_dcache_remove(struct v_dnode* dnode) { + assert(dnode); assert(dnode->ref_count == 1); llist_delete(&dnode->siblings); + llist_delete(&dnode->aka_list); hlist_delete(&dnode->hash_list); dnode->parent = NULL; @@ -184,170 +174,13 @@ vfs_dcache_remove(struct v_dnode* dnode) void vfs_dcache_rehash(struct v_dnode* new_parent, struct v_dnode* dnode) { + assert(new_parent); + hstr_rehash(&dnode->name, HSTR_FULL_HASH); vfs_dcache_remove(dnode); vfs_dcache_add(new_parent, dnode); } -int -__vfs_walk(struct v_dnode* start, - const char* path, - struct v_dnode** dentry, - struct hstr* component, - int walk_options) -{ - int errno = 0; - int i = 0, j = 0; - - if (path[0] == PATH_DELIM || !start) { - if ((walk_options & VFS_WALK_FSRELATIVE) && start) { - start = start->super_block->root; - } else { - start = vfs_sysroot; - if (!vfs_sysroot->mnt) { - panick("vfs: no root"); - } - } - i++; - } - - struct v_dnode* dnode; - struct v_dnode* current_level = start; - - char name_content[VFS_NAME_MAXLEN]; - struct hstr name = HSTR(name_content, 0); - - char current = path[i++], lookahead; - while (current && current_level) { - lookahead = path[i++]; - if (current != PATH_DELIM) { - if (j >= VFS_NAME_MAXLEN - 1) { - return ENAMETOOLONG; - } - if (!VFS_VALID_CHAR(current)) { - return EINVAL; - } - name_content[j++] = current; - if (lookahead) { - goto cont; - } - } - - // handling cases like /^.*(\/+).*$/ - if (lookahead == PATH_DELIM) { - goto cont; - } - - lock_dnode(current_level); - - name_content[j] = 0; - name.len = j; - hstr_rehash(&name, HSTR_FULL_HASH); - - if (!lookahead && (walk_options & VFS_WALK_PARENT)) { - if (component) { - component->hash = name.hash; - component->len = j; - strcpy(component->value, name_content); - } - unlock_dnode(current_level); - break; - } - - dnode = vfs_dcache_lookup(current_level, &name); - - if (!dnode) { - dnode = vfs_d_alloc(current_level, &name); - - if (!dnode) { - errno = ENOMEM; - goto error; - } - - struct v_inode* current_inode = current_level->inode; - - lock_inode(current_inode); - - errno = current_inode->ops->dir_lookup(current_inode, dnode); - - if (errno == ENOENT && (walk_options & VFS_WALK_MKPARENT)) { - if (!current_inode->ops->mkdir) { - errno = ENOTSUP; - } else { - errno = current_inode->ops->mkdir(current_inode, dnode); - } - } - - vfs_dcache_add(current_level, dnode); - unlock_inode(current_inode); - - if (errno) { - unlock_dnode(current_level); - goto cleanup; - } - } - - unlock_dnode(current_level); - - j = 0; - current_level = dnode; - cont: - current = lookahead; - }; - - *dentry = current_level; - return 0; - -cleanup: - vfs_d_free(dnode); -error: - *dentry = NULL; - return errno; -} - -#define VFS_MAX_SYMLINK 16 - -int -vfs_walk(struct v_dnode* start, - const char* path, - struct v_dnode** dentry, - struct hstr* component, - int options) -{ - struct v_dnode* interim; - const char* pathname = path; - int errno = __vfs_walk(start, path, &interim, component, options); - int counter = 0; - - // FIXME This is NOT a correct way to resolve symlink! - while (!errno && interim->inode && (options & VFS_WALK_NOFOLLOW)) { - if (counter >= VFS_MAX_SYMLINK) { - errno = ELOOP; - continue; - } - if ((interim->inode->itype & VFS_IFSYMLINK) && - interim->inode->ops->read_symlink) { - - lock_inode(interim->inode); - errno = - interim->inode->ops->read_symlink(interim->inode, &pathname); - unlock_inode(interim->inode); - - if (errno) { - break; - } - } else { - break; - } - errno = __vfs_walk(start, pathname, &interim, component, options); - counter++; - } - - *dentry = errno ? 0 : interim; - - return errno; -} - int vfs_open(struct v_dnode* dnode, struct v_file** file) { @@ -367,7 +200,7 @@ vfs_open(struct v_dnode* dnode, struct v_file** file) vfile->ref_count = ATOMIC_VAR_INIT(1); vfile->ops = inode->default_fops; - if ((inode->itype & VFS_IFFILE) && !inode->pg_cache) { + if ((inode->itype & F_MFILE) && !inode->pg_cache) { struct pcache* pcache = vzalloc(sizeof(struct pcache)); pcache_init(pcache); pcache->master = inode; @@ -394,8 +227,10 @@ void vfs_assign_inode(struct v_dnode* assign_to, struct v_inode* inode) { if (assign_to->inode) { + llist_delete(&assign_to->aka_list); assign_to->inode->link_count--; } + llist_append(&inode->aka_dnodes, &assign_to->aka_list); assign_to->inode = inode; inode->link_count++; } @@ -405,6 +240,10 @@ vfs_link(struct v_dnode* to_link, struct v_dnode* name) { int errno; + if ((errno = vfs_check_writable(to_link))) { + return errno; + } + lock_inode(to_link->inode); if (to_link->super_block->root != name->super_block->root) { errno = EXDEV; @@ -419,12 +258,35 @@ vfs_link(struct v_dnode* to_link, struct v_dnode* name) } int -vfs_close(struct v_file* file) +vfs_pclose(struct v_file* file, pid_t pid) { int errno = 0; - if (!(errno = file->ops->close(file))) { + if (file->ref_count > 1) { + atomic_fetch_sub(&file->ref_count, 1); + } else if (!(errno = file->ops->close(file))) { atomic_fetch_sub(&file->dnode->ref_count, 1); file->inode->open_count--; + + /* + * Prevent dead lock. + * This happened when process is terminated while blocking on read. + * In that case, the process is still holding the inode lock and it + will never get released. + * The unlocking should also include ownership check. + * + * To see why, consider two process both open the same file both with + * fd=x. + * Process A: busy on reading x + * Process B: do nothing with x + * Assuming that, after a very short time, process B get terminated + * while process A is still busy in it's reading business. By this + * design, the inode lock of this file x is get released by B rather + * than A. And this will cause a probable race condition on A if other + * process is writing to this file later after B exit. + */ + if (mutex_on_hold(&file->inode->lock)) { + mutex_unlock_for(&file->inode->lock, pid); + } mnt_chillax(file->dnode->mnt); pcache_commit_all(file->inode); @@ -433,14 +295,31 @@ vfs_close(struct v_file* file) return errno; } +int +vfs_close(struct v_file* file) +{ + return vfs_pclose(file, __current->pid); +} + +void +vfs_free_fd(struct v_fd* fd) +{ + cake_release(fd_pile, fd); +} + int vfs_fsync(struct v_file* file) { + int errno; + if ((errno = vfs_check_writable(file->dnode))) { + return errno; + } + lock_inode(file->inode); - int errno = ENOTSUP; pcache_commit_all(file->inode); + errno = ENOTSUP; if (file->ops->sync) { errno = file->ops->sync(file); } @@ -518,6 +397,7 @@ vfs_d_alloc(struct v_dnode* parent, struct hstr* name) memset(dnode, 0, sizeof(*dnode)); llist_init_head(&dnode->children); llist_init_head(&dnode->siblings); + llist_init_head(&dnode->aka_list); mutex_init(&dnode->lock); dnode->ref_count = ATOMIC_VAR_INIT(0); @@ -527,6 +407,7 @@ vfs_d_alloc(struct v_dnode* parent, struct hstr* name) if (parent) { dnode->super_block = parent->super_block; + dnode->mnt = parent->mnt; } lru_use_one(dnode_lru, &dnode->lru); @@ -554,12 +435,12 @@ vfs_d_free(struct v_dnode* dnode) vfs_dcache_remove(pos); } - vfree(dnode->name.value); + vfree((void*)dnode->name.value); cake_release(dnode_pile, dnode); } struct v_inode* -vfs_i_find(struct v_superblock* sb, uint32_t i_id) +vfs_i_find(struct v_superblock* sb, u32_t i_id) { struct hbucket* slot = &sb->i_cache[i_id & VFS_HASH_MASK]; struct v_inode *pos, *n; @@ -598,6 +479,8 @@ vfs_i_alloc(struct v_superblock* sb) memset(inode, 0, sizeof(*inode)); mutex_init(&inode->lock); + llist_init_head(&inode->xattrs); + llist_init_head(&inode->aka_dnodes); sb->ops.init_inode(sb, inode); @@ -606,7 +489,6 @@ vfs_i_alloc(struct v_superblock* sb) inode->atime = inode->ctime; inode->mtime = inode->ctime; -done: lru_use_one(inode_lru, &inode->lru); return inode; } @@ -618,7 +500,12 @@ vfs_i_free(struct v_inode* inode) pcache_release(inode->pg_cache); vfree(inode->pg_cache); } - inode->ops->sync(inode); + // we don't need to sync inode. + // If an inode can be free, then it must be properly closed. + // Hence it must be synced already! + if (inode->destruct) { + inode->destruct(inode); + } hlist_delete(&inode->hash_list); cake_release(inode_pile, inode); } @@ -626,9 +513,11 @@ vfs_i_free(struct v_inode* inode) /* ---- System call definition and support ---- */ #define FLOCATE_CREATE_EMPTY 1 +#define FLOCATE_CREATE_ONLY 2 +#define FLOCATE_NOFOLLOW 4 int -__vfs_getfd(int fd, struct v_fd** fd_s) +vfs_getfd(int fd, struct v_fd** fd_s) { if (TEST_FD(fd) && (*fd_s = __current->fdtable->fds[fd])) { return 0; @@ -644,14 +533,25 @@ __vfs_try_locate_file(const char* path, { char name_str[VFS_NAME_MAXLEN]; struct hstr name = HSTR(name_str, 0); - int errno; - if ((errno = - vfs_walk(__current->cwd, path, fdir, &name, VFS_WALK_PARENT))) { + int errno, woption = 0; + + if ((options & FLOCATE_NOFOLLOW)) { + woption |= VFS_WALK_NOFOLLOW; + } + + name_str[0] = 0; + if ((errno = vfs_walk_proc(path, fdir, &name, woption | VFS_WALK_PARENT))) { return errno; } - errno = vfs_walk(*fdir, name.value, file, NULL, 0); - if (errno != ENOENT || !(options & FLOCATE_CREATE_EMPTY)) { + errno = vfs_walk(*fdir, name.value, file, NULL, woption); + + if (errno != ENOENT && (options & FLOCATE_CREATE_ONLY)) { + return EEXIST; + } + + if (errno != ENOENT || + !(options & (FLOCATE_CREATE_EMPTY | FLOCATE_CREATE_ONLY))) { return errno; } @@ -679,21 +579,27 @@ __vfs_try_locate_file(const char* path, int vfs_do_open(const char* path, int options) { - int errno, fd; + int errno, fd, loptions = 0; struct v_dnode *dentry, *file; - struct v_file* ofile = 0; - - errno = __vfs_try_locate_file( - path, &dentry, &file, (options & FO_CREATE) ? FLOCATE_CREATE_EMPTY : 0); + struct v_file* ofile = NULL; - if (errno || (errno = vfs_open(file, &ofile))) { - return errno; + if ((options & FO_CREATE)) { + loptions |= FLOCATE_CREATE_EMPTY; + } else if ((options & FO_NOFOLLOW)) { + loptions |= FLOCATE_NOFOLLOW; } - struct v_inode* o_inode = ofile->inode; + errno = __vfs_try_locate_file(path, &dentry, &file, loptions); if (!errno && !(errno = vfs_alloc_fdslot(&fd))) { - struct v_fd* fd_s = vzalloc(sizeof(*fd_s)); + + if (errno || (errno = vfs_open(file, &ofile))) { + return errno; + } + + struct v_fd* fd_s = cake_grab(fd_pile); + memset(fd_s, 0, sizeof(*fd_s)); + ofile->f_pos = ofile->inode->fsize & -((options & FO_APPEND) != 0); fd_s->file = ofile; fd_s->flags = options; @@ -714,17 +620,15 @@ __DEFINE_LXSYSCALL1(int, close, int, fd) { struct v_fd* fd_s; int errno = 0; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done_err; } - if (fd_s->file->ref_count > 1) { - fd_s->file->ref_count--; - } else if ((errno = vfs_close(fd_s->file))) { + if ((errno = vfs_close(fd_s->file))) { goto done_err; } - vfree(fd_s); + cake_release(fd_pile, fd_s); __current->fdtable->fds[fd] = 0; done_err: @@ -737,18 +641,18 @@ __vfs_readdir_callback(struct dir_context* dctx, const int len, const int dtype) { - struct dirent* dent = (struct dirent*)dctx->cb_data; + struct lx_dirent* dent = (struct lx_dirent*)dctx->cb_data; strncpy(dent->d_name, name, DIRENT_NAME_MAX_LEN); dent->d_nlen = len; dent->d_type = dtype; } -__DEFINE_LXSYSCALL2(int, readdir, int, fd, struct dirent*, dent) +__DEFINE_LXSYSCALL2(int, sys_readdir, int, fd, struct lx_dirent*, dent) { struct v_fd* fd_s; int errno; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } @@ -756,19 +660,18 @@ __DEFINE_LXSYSCALL2(int, readdir, int, fd, struct dirent*, dent) lock_inode(inode); - if (!(inode->itype & VFS_IFDIR)) { + if ((inode->itype & F_FILE)) { errno = ENOTDIR; } else { - struct dir_context dctx = - (struct dir_context){ .cb_data = dent, - .index = dent->d_offset, - .read_complete_callback = - __vfs_readdir_callback }; + struct dir_context dctx = (struct dir_context){ + .cb_data = dent, + .index = dent->d_offset, + .read_complete_callback = __vfs_readdir_callback}; errno = 1; if (dent->d_offset == 0) { - __vfs_readdir_callback(&dctx, vfs_dot.value, vfs_dot.len, 0); + __vfs_readdir_callback(&dctx, vfs_dot.value, vfs_dot.len, DT_DIR); } else if (dent->d_offset == 1) { - __vfs_readdir_callback(&dctx, vfs_ddot.value, vfs_ddot.len, 0); + __vfs_readdir_callback(&dctx, vfs_ddot.value, vfs_ddot.len, DT_DIR); } else { dctx.index -= 2; if ((errno = fd_s->file->ops->readdir(fd_s->file, &dctx)) != 1) { @@ -789,12 +692,12 @@ __DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count) { int errno = 0; struct v_fd* fd_s; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } struct v_file* file = fd_s->file; - if ((file->inode->itype & VFS_IFDIR)) { + if (!(file->inode->itype & F_FILE)) { errno = EISDIR; goto done; } @@ -803,13 +706,11 @@ __DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count) file->inode->atime = clock_unixtime(); - __SYSCALL_INTERRUPTIBLE({ - if ((file->inode->itype & VFS_IFSEQDEV) || (fd_s->flags & FO_DIRECT)) { - errno = file->ops->read(file->inode, buf, count, file->f_pos); - } else { - errno = pcache_read(file->inode, buf, count, file->f_pos); - } - }) + if ((file->inode->itype & VFS_IFSEQDEV) || (fd_s->flags & FO_DIRECT)) { + errno = file->ops->read(file->inode, buf, count, file->f_pos); + } else { + errno = pcache_read(file->inode, buf, count, file->f_pos); + } if (errno > 0) { file->f_pos += errno; @@ -827,12 +728,17 @@ __DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count) { int errno = 0; struct v_fd* fd_s; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } struct v_file* file = fd_s->file; - if ((file->inode->itype & VFS_IFDIR)) { + + if ((errno = vfs_check_writable(file->dnode))) { + goto done; + } + + if (!(file->inode->itype & F_FILE)) { errno = EISDIR; goto done; } @@ -841,13 +747,11 @@ __DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count) file->inode->mtime = clock_unixtime(); - __SYSCALL_INTERRUPTIBLE({ - if ((file->inode->itype & VFS_IFSEQDEV) || (fd_s->flags & FO_DIRECT)) { - errno = file->ops->write(file->inode, buf, count, file->f_pos); - } else { - errno = pcache_write(file->inode, buf, count, file->f_pos); - } - }) + if ((file->inode->itype & VFS_IFSEQDEV) || (fd_s->flags & FO_DIRECT)) { + errno = file->ops->write(file->inode, buf, count, file->f_pos); + } else { + errno = pcache_write(file->inode, buf, count, file->f_pos); + } if (errno > 0) { file->f_pos += errno; @@ -865,27 +769,35 @@ __DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options) { int errno = 0; struct v_fd* fd_s; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } struct v_file* file = fd_s->file; + if (!file->ops->seek) { + errno = ENOTSUP; + goto done; + } + lock_inode(file->inode); - size_t fpos = file->f_pos; + int overflow = 0; + int fpos = file->f_pos; switch (options) { case FSEEK_CUR: - fpos = (size_t)((int)file->f_pos + offset); + overflow = sadd_overflow((int)file->f_pos, offset, &fpos); break; case FSEEK_END: - fpos = (size_t)((int)file->inode->fsize + offset); + overflow = sadd_overflow((int)file->inode->fsize, offset, &fpos); break; case FSEEK_SET: fpos = offset; break; } - if (!(errno = file->ops->seek(file->inode, fpos))) { + if (overflow) { + errno = EOVERFLOW; + } else if (!(errno = file->ops->seek(file->inode, fpos))) { file->f_pos = fpos; } @@ -903,23 +815,27 @@ vfs_get_path(struct v_dnode* dnode, char* buf, size_t size, int depth) } if (depth > 64) { - return ELOOP; + return ENAMETOOLONG; } - size_t len = vfs_get_path(dnode->parent, buf, size, depth + 1); + size_t len = 0; + + if (dnode->parent != dnode) { + len = vfs_get_path(dnode->parent, buf, size, depth + 1); + } if (len >= size) { return len; } + if (!len || buf[len - 1] != VFS_PATH_DELIM) { + buf[len++] = VFS_PATH_DELIM; + } + size_t cpy_size = MIN(dnode->name.len, size - len); strncpy(buf + len, dnode->name.value, cpy_size); len += cpy_size; - if (len < size) { - buf[len++] = PATH_DELIM; - } - return len; } @@ -940,11 +856,23 @@ vfs_readlink(struct v_dnode* dnode, char* buf, size_t size) return 0; } +int +vfs_get_dtype(int itype) +{ + if ((itype & VFS_IFSYMLINK) == VFS_IFSYMLINK) { + return DT_SYMLINK; + } else if (!(itype & VFS_IFFILE)) { + return DT_DIR; + } else { + return DT_FILE; + } +} + __DEFINE_LXSYSCALL3(int, realpathat, int, fd, char*, buf, size_t, size) { int errno; struct v_fd* fd_s; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } @@ -963,8 +891,7 @@ __DEFINE_LXSYSCALL3(int, readlink, const char*, path, char*, buf, size_t, size) { int errno; struct v_dnode* dnode; - if (!(errno = - vfs_walk(__current->cwd, path, &dnode, NULL, VFS_WALK_NOFOLLOW))) { + if (!(errno = vfs_walk_proc(path, &dnode, NULL, VFS_WALK_NOFOLLOW))) { errno = vfs_readlink(dnode, buf, size); } @@ -975,23 +902,17 @@ __DEFINE_LXSYSCALL3(int, readlink, const char*, path, char*, buf, size_t, size) return DO_STATUS(errno); } -__DEFINE_LXSYSCALL4(int, - readlinkat, - int, - dirfd, - const char*, - pathname, - char*, - buf, - size_t, - size) +__DEFINE_LXSYSCALL4( + int, readlinkat, int, dirfd, const char*, pathname, char*, buf, size_t, size) { int errno; struct v_fd* fd_s; - if ((errno = __vfs_getfd(dirfd, &fd_s))) { + if ((errno = vfs_getfd(dirfd, &fd_s))) { goto done; } + pathname = pathname ? pathname : ""; + struct v_dnode* dnode; if (!(errno = vfs_walk( fd_s->file->dnode, pathname, &dnode, NULL, VFS_WALK_NOFOLLOW))) { @@ -1018,12 +939,16 @@ __DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname) { int errno; struct v_dnode* dnode; - if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) { + if ((errno = vfs_walk_proc(pathname, &dnode, NULL, 0))) { return DO_STATUS(errno); } lock_dnode(dnode); + if ((errno = vfs_check_writable(dnode))) { + goto done; + } + if ((dnode->super_block->fs->types & FSTYPE_ROFS)) { errno = EROFS; goto done; @@ -1049,7 +974,7 @@ __DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname) lock_dnode(parent); lock_inode(parent->inode); - if ((dnode->inode->itype & VFS_IFDIR)) { + if (!(dnode->inode->itype & F_MFILE)) { errno = parent->inode->ops->rmdir(parent->inode, dnode); if (!errno) { vfs_dcache_remove(dnode); @@ -1073,17 +998,23 @@ __DEFINE_LXSYSCALL1(int, mkdir, const char*, path) char name_value[VFS_NAME_MAXLEN]; struct hstr name = HHSTR(name_value, 0, 0); - if (!dir) { - errno = ENOMEM; + if ((errno = vfs_walk_proc(path, &parent, &name, VFS_WALK_PARENT))) { goto done; } - if ((errno = - vfs_walk(__current->cwd, path, &parent, &name, VFS_WALK_PARENT))) { + if (!(errno = vfs_walk(parent, name_value, &dir, NULL, 0))) { + errno = EEXIST; goto done; } - dir = vfs_d_alloc(parent, &name); + if ((errno = vfs_check_writable(parent))) { + goto done; + } + + if (!(dir = vfs_d_alloc(parent, &name))) { + errno = ENOMEM; + goto done; + } lock_dnode(parent); lock_inode(parent->inode); @@ -1092,7 +1023,7 @@ __DEFINE_LXSYSCALL1(int, mkdir, const char*, path) errno = ENOTSUP; } else if (!parent->inode->ops->mkdir) { errno = ENOTSUP; - } else if (!(parent->inode->itype & VFS_IFDIR)) { + } else if ((parent->inode->itype & F_FILE)) { errno = ENOTDIR; } else if (!(errno = parent->inode->ops->mkdir(parent->inode, dir))) { vfs_dcache_add(parent, dir); @@ -1111,20 +1042,22 @@ done: int __vfs_do_unlink(struct v_dnode* dnode) { + int errno; struct v_inode* inode = dnode->inode; if (dnode->ref_count > 1) { return EBUSY; } + if ((errno = vfs_check_writable(dnode))) { + return errno; + } + lock_inode(inode); - int errno; if (inode->open_count) { errno = EBUSY; - } else if (!(inode->itype & VFS_IFDIR)) { - // The underlying unlink implementation should handle - // symlink case + } else if ((inode->itype & F_MFILE)) { errno = inode->ops->unlink(inode); if (!errno) { vfs_d_free(dnode); @@ -1142,11 +1075,7 @@ __DEFINE_LXSYSCALL1(int, unlink, const char*, pathname) { int errno; struct v_dnode* dnode; - if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) { - goto done; - } - if ((dnode->super_block->fs->types & FSTYPE_ROFS)) { - errno = EROFS; + if ((errno = vfs_walk_proc(pathname, &dnode, NULL, 0))) { goto done; } @@ -1160,7 +1089,7 @@ __DEFINE_LXSYSCALL2(int, unlinkat, int, fd, const char*, pathname) { int errno; struct v_fd* fd_s; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } @@ -1181,10 +1110,8 @@ __DEFINE_LXSYSCALL2(int, link, const char*, oldpath, const char*, newpath) errno = __vfs_try_locate_file(oldpath, &dentry, &to_link, 0); if (!errno) { errno = __vfs_try_locate_file( - newpath, &name_dentry, &name_file, FLOCATE_CREATE_EMPTY); + newpath, &name_dentry, &name_file, FLOCATE_CREATE_ONLY); if (!errno) { - errno = EEXIST; - } else if (name_file) { errno = vfs_link(to_link, name_file); } } @@ -1195,7 +1122,8 @@ __DEFINE_LXSYSCALL1(int, fsync, int, fildes) { int errno; struct v_fd* fd_s; - if (!(errno = __vfs_getfd(fildes, &fd_s))) { + + if (!(errno = vfs_getfd(fildes, &fd_s))) { errno = vfs_fsync(fd_s->file); } @@ -1226,7 +1154,7 @@ vfs_dup2(int oldfd, int newfd) int errno; struct v_fd *oldfd_s, *newfd_s; - if ((errno = __vfs_getfd(oldfd, &oldfd_s))) { + if ((errno = vfs_getfd(oldfd, &oldfd_s))) { goto done; } @@ -1258,7 +1186,7 @@ __DEFINE_LXSYSCALL1(int, dup, int, oldfd) { int errno, newfd; struct v_fd *oldfd_s, *newfd_s; - if ((errno = __vfs_getfd(oldfd, &oldfd_s))) { + if ((errno = vfs_getfd(oldfd, &oldfd_s))) { goto done; } @@ -1272,57 +1200,78 @@ done: return DO_STATUS(errno); } -__DEFINE_LXSYSCALL2(int, - symlink, - const char*, - pathname, - const char*, - link_target) +__DEFINE_LXSYSCALL2( + int, symlink, const char*, pathname, const char*, link_target) { int errno; - struct v_dnode* dnode; - if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) { + struct v_dnode *dnode, *file; + if ((errno = __vfs_try_locate_file( + pathname, &dnode, &file, FLOCATE_CREATE_ONLY))) { goto done; } - if ((dnode->super_block->fs->types & FSTYPE_ROFS)) { - errno = EROFS; + + if ((errno = vfs_check_writable(file))) { goto done; } - if (!dnode->inode->ops->set_symlink) { + + if (!file->inode->ops->set_symlink) { errno = ENOTSUP; goto done; } - lock_inode(dnode->inode); + lock_inode(file->inode); - errno = dnode->inode->ops->set_symlink(dnode->inode, link_target); + errno = file->inode->ops->set_symlink(file->inode, link_target); - unlock_inode(dnode->inode); + unlock_inode(file->inode); done: return DO_STATUS(errno); } +void +vfs_ref_file(struct v_file* file) +{ + atomic_fetch_add(&file->ref_count, 1); +} + +void +vfs_ref_dnode(struct v_dnode* dnode) +{ + atomic_fetch_add(&dnode->ref_count, 1); + + if (dnode->mnt) { + mnt_mkbusy(dnode->mnt); + } +} + +void +vfs_unref_dnode(struct v_dnode* dnode) +{ + atomic_fetch_sub(&dnode->ref_count, 1); + if (dnode->mnt) { + mnt_chillax(dnode->mnt); + } +} + int -__vfs_do_chdir(struct v_dnode* dnode) +vfs_do_chdir(struct proc_info* proc, struct v_dnode* dnode) { int errno = 0; lock_dnode(dnode); - if (!(dnode->inode->itype & VFS_IFDIR)) { + if ((dnode->inode->itype & F_FILE)) { errno = ENOTDIR; goto done; } - if (__current->cwd) { - atomic_fetch_sub(&__current->cwd->ref_count, 1); - mnt_chillax(__current->cwd->mnt); + if (proc->cwd) { + vfs_unref_dnode(proc->cwd); } - atomic_fetch_add(&dnode->ref_count, 1); - mnt_mkbusy(dnode->mnt); - __current->cwd = dnode; + vfs_ref_dnode(dnode); + proc->cwd = dnode; unlock_dnode(dnode); @@ -1335,11 +1284,11 @@ __DEFINE_LXSYSCALL1(int, chdir, const char*, path) struct v_dnode* dnode; int errno = 0; - if ((errno = vfs_walk(__current->cwd, path, &dnode, NULL, 0))) { + if ((errno = vfs_walk_proc(path, &dnode, NULL, 0))) { goto done; } - errno = __vfs_do_chdir(dnode); + errno = vfs_do_chdir((struct proc_info*)__current, dnode); done: return DO_STATUS(errno); @@ -1350,11 +1299,11 @@ __DEFINE_LXSYSCALL1(int, fchdir, int, fd) struct v_fd* fd_s; int errno = 0; - if ((errno = __vfs_getfd(fd, &fd_s))) { + if ((errno = vfs_getfd(fd, &fd_s))) { goto done; } - errno = __vfs_do_chdir(fd_s->file->dnode); + errno = vfs_do_chdir((struct proc_info*)__current, fd_s->file->dnode); done: return DO_STATUS(errno); @@ -1372,7 +1321,7 @@ __DEFINE_LXSYSCALL2(char*, getcwd, char*, buf, size_t, size) size_t len = 0; if (!__current->cwd) { - *buf = PATH_DELIM; + *buf = VFS_PATH_DELIM; len = 1; } else { len = vfs_get_path(__current->cwd, buf, size, 0); @@ -1382,23 +1331,28 @@ __DEFINE_LXSYSCALL2(char*, getcwd, char*, buf, size_t, size) } } - buf[len + 1] = '\0'; + buf[len] = '\0'; ret_ptr = buf; done: - __current->k_status = errno; + syscall_result(errno); return ret_ptr; } int vfs_do_rename(struct v_dnode* current, struct v_dnode* target) { + int errno = 0; if (current->inode->id == target->inode->id) { // hard link return 0; } + if ((errno = vfs_check_writable(current))) { + return errno; + } + if (current->ref_count > 1 || target->ref_count > 1) { return EBUSY; } @@ -1407,8 +1361,6 @@ vfs_do_rename(struct v_dnode* current, struct v_dnode* target) return EXDEV; } - int errno = 0; - struct v_dnode* oldparent = current->parent; struct v_dnode* newparent = target->parent; @@ -1456,7 +1408,7 @@ __DEFINE_LXSYSCALL2(int, rename, const char*, oldpath, const char*, newpath) struct hstr name = HSTR(valloc(VFS_NAME_MAXLEN), 0); int errno = 0; - if ((errno = vfs_walk(__current->cwd, oldpath, &cur, NULL, 0))) { + if ((errno = vfs_walk_proc(oldpath, &cur, NULL, 0))) { goto done; } @@ -1481,6 +1433,47 @@ __DEFINE_LXSYSCALL2(int, rename, const char*, oldpath, const char*, newpath) errno = vfs_do_rename(cur, target); done: - vfree(name.value); + vfree((void*)name.value); + return DO_STATUS(errno); +} + +__DEFINE_LXSYSCALL2(int, fstat, int, fd, struct file_stat*, stat) +{ + int errno = 0; + struct v_fd* fds; + + if ((errno = vfs_getfd(fd, &fds))) { + goto done; + } + + struct v_inode* vino = fds->file->inode; + struct device* fdev = vino->sb->dev; + + *stat = (struct file_stat){.st_ino = vino->id, + .st_blocks = vino->lb_usage, + .st_size = vino->fsize, + .mode = vino->itype, + .st_ioblksize = PAGE_SIZE, + .st_blksize = vino->sb->blksize}; + + if (VFS_DEVFILE(vino->itype)) { + struct device* rdev = resolve_device(vino->data); + if (!rdev || rdev->magic != DEV_STRUCT_MAGIC) { + errno = EINVAL; + goto done; + } + + stat->st_rdev = (dev_t){.meta = rdev->ident.fn_grp, + .unique = rdev->ident.unique, + .index = rdev->dev_uid}; + } + + if (fdev) { + stat->st_dev = (dev_t){.meta = fdev->ident.fn_grp, + .unique = fdev->ident.unique, + .index = fdev->dev_uid}; + } + +done: return DO_STATUS(errno); } \ No newline at end of file