+}
+
+struct v_inode*
+vfs_i_alloc()
+{
+ struct v_inode* inode = cake_grab(inode_pile);
+ memset(inode, 0, sizeof(*inode));
+ return inode;
+}
+
+void
+vfs_i_free(struct v_inode* inode)
+{
+ cake_release(inode_pile, inode);
+}
+
+/* ---- System call definition and support ---- */
+
+#define FLOCATE_CREATE_EMPTY 1
+
+#define DO_STATUS(errno) SYSCALL_ESTATUS(__current->k_status = errno)
+#define DO_STATUS_OR_RETURN(errno) ({ errno < 0 ? DO_STATUS(errno) : errno; })
+
+int
+__vfs_try_locate_file(const char* path,
+ struct v_dnode** fdir,
+ struct v_dnode** file,
+ int options)
+{
+ char name_str[VFS_NAME_MAXLEN];
+ struct hstr name = HSTR(name_str, 0);
+ int errno;
+ if ((errno = vfs_walk(NULL, path, fdir, &name, VFS_WALK_PARENT))) {
+ return errno;
+ }
+
+ errno = vfs_walk(*fdir, name.value, file, NULL, 0);
+ if (errno != ENOENT || !(options & FLOCATE_CREATE_EMPTY)) {
+ return errno;
+ }
+
+ if (!(errno = (*fdir)->inode->ops.create((*fdir)->inode))) {
+ struct v_dnode* file_new;
+ file_new = vfs_d_alloc();
+ file_new->name = HHSTR(valloc(VFS_NAME_MAXLEN), name.len, name.hash);
+ strcpy(file_new->name.value, name_str);
+ *file = file_new;
+
+ llist_append(&(*fdir)->children, &file_new->siblings);
+ }
+
+ return errno;
+}
+
+int
+__file_cached_read(struct v_file* file, void* buf, size_t len, size_t fpos)
+{
+ return pcache_read(file, buf, len, fpos);
+}
+
+int
+vfs_do_open(const char* path, int options)
+{
+ int errno, fd;
+ struct v_dnode *dentry, *file;
+ struct v_file* ofile = 0;
+
+ errno = __vfs_try_locate_file(path, &dentry, &file, 0);
+
+ if (errno != ENOENT && (options & FO_CREATE)) {
+ errno = dentry->inode->ops.create(dentry->inode);
+ }
+
+ if (!errno && (errno = vfs_open(file, &ofile))) {
+ return errno;
+ }
+
+ struct v_inode* o_inode = ofile->inode;
+ if (!(o_inode->itype & VFS_IFSEQDEV) && !(options & FO_DIRECT)) {
+ // XXX Change here accordingly when signature of pcache_r/w changed.
+ ofile->ops.read = pcache_read;
+ ofile->ops.write = pcache_write;
+ }
+
+ if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {
+ struct v_fd* fd_s = vzalloc(sizeof(*fd_s));
+ ofile->f_pos = ofile->inode->fsize & -((options & FO_APPEND) != 0);
+ fd_s->file = ofile;
+ fd_s->flags = options;
+ __current->fdtable->fds[fd] = fd_s;
+ return fd;
+ }
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
+{
+ int errno = vfs_do_open(path, options);
+ return DO_STATUS_OR_RETURN(errno);
+}
+
+#define TEST_FD(fd) (fd >= 0 && fd < VFS_MAX_FD)
+#define GET_FD(fd, fd_s) (TEST_FD(fd) && (fd_s = __current->fdtable->fds[fd]))
+
+__DEFINE_LXSYSCALL1(int, close, int, fd)
+{
+ struct v_fd* fd_s;
+ int errno = 0;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ goto done_err;
+ }
+
+ if (fd_s->file->ref_count > 1) {
+ fd_s->file->ref_count--;
+ } else if ((errno = vfs_close(fd_s->file))) {
+ goto done_err;
+ }
+
+ vfree(fd_s);
+ __current->fdtable->fds[fd] = 0;
+
+done_err:
+ return DO_STATUS(errno);
+}
+
+void
+__vfs_readdir_callback(struct dir_context* dctx,
+ const char* name,
+ const int len,
+ const int dtype)
+{
+ struct dirent* dent = (struct 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)
+{
+ struct v_fd* fd_s;
+ int errno;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ } else if (!(fd_s->file->inode->itype & VFS_IFDIR)) {
+ errno = ENOTDIR;
+ } else {
+ struct dir_context dctx =
+ (struct dir_context){ .cb_data = dent,
+ .index = dent->d_offset,
+ .read_complete_callback =
+ __vfs_readdir_callback };
+ if (dent->d_offset == 0) {
+ __vfs_readdir_callback(&dctx, vfs_dot.value, vfs_dot.len, 0);
+ } else if (dent->d_offset == 1) {
+ __vfs_readdir_callback(&dctx, vfs_ddot.value, vfs_ddot.len, 0);
+ } else {
+ dctx.index -= 2;
+ if ((errno = fd_s->file->ops.readdir(fd_s->file, &dctx))) {
+ goto done;
+ }
+ }
+ errno = 0;
+ dent->d_offset++;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
+{
+ struct v_dnode *parent, *dir;
+ struct hstr component = HSTR(valloc(VFS_NAME_MAXLEN), 0);
+ int errno = vfs_walk(NULL, path, &parent, &component, VFS_WALK_PARENT);
+ if (errno) {
+ goto done;
+ }
+
+ if ((parent->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = ENOTSUP;
+ } else if (!parent->inode->ops.mkdir) {
+ errno = ENOTSUP;
+ } else if (!(parent->inode->itype & VFS_IFDIR)) {
+ errno = ENOTDIR;
+ } else {
+ dir = vfs_d_alloc();
+ dir->name = component;
+ if (!(errno = parent->inode->ops.mkdir(parent->inode, dir))) {
+ llist_append(&parent->children, &dir->siblings);
+ } else {
+ vfs_d_free(dir);
+ vfree(component.value);
+ }
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
+ }
+
+ errno = file->ops.read(file, buf, count, file->f_pos);
+
+ if (errno > 0) {
+ file->f_pos += errno;
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
+ }
+
+ errno = file->ops.write(file, buf, count, file->f_pos);
+
+ if (errno > 0) {
+ file->f_pos += errno;
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ } else {
+ struct v_file* file = fd_s->file;
+ size_t fpos = file->f_pos;
+ switch (options) {
+ case FSEEK_CUR:
+ fpos = (size_t)((int)file->f_pos + offset);
+ break;
+ case FSEEK_END:
+ fpos = (size_t)((int)file->inode->fsize + offset);
+ break;
+ case FSEEK_SET:
+ fpos = offset;
+ break;
+ }
+ if (!file->ops.seek || !(errno = file->ops.seek(file, fpos))) {
+ file->f_pos = fpos;
+ }
+ }
+
+ return DO_STATUS(errno);
+}
+
+int
+vfs_get_path(struct v_dnode* dnode, char* buf, size_t size, int depth)
+{
+ if (!dnode) {
+ return 0;
+ }
+
+ if (depth > 64) {
+ return ELOOP;
+ }
+
+ size_t len = vfs_get_path(dnode->parent, buf, size, depth + 1);
+
+ if (len >= size) {
+ return len;
+ }
+
+ 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;
+}
+
+int
+vfs_readlink(struct v_dnode* dnode, char* buf, size_t size)
+{
+ char* link;
+ if (dnode->inode->ops.read_symlink) {
+ int errno = dnode->inode->ops.read_symlink(dnode->inode, &link);
+ strncpy(buf, link, size);
+ return errno;
+ }
+ return 0;
+}
+
+__DEFINE_LXSYSCALL3(int, realpathat, int, fd, char*, buf, size_t, size)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ } else {
+ struct v_dnode* dnode;
+ errno = vfs_get_path(fd_s->file->dnode, buf, size, 0);
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, readlink, const char*, path, char*, buf, size_t, size)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if (!(errno = vfs_walk(NULL, path, &dnode, NULL, VFS_WALK_NOFOLLOW))) {
+ errno = vfs_readlink(dnode, buf, size);
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL4(int,
+ readlinkat,
+ int,
+ dirfd,
+ const char*,
+ pathname,
+ char*,
+ buf,
+ size_t,
+ size)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if (!GET_FD(dirfd, fd_s)) {
+ errno = EBADF;
+ } else {
+ struct v_dnode* dnode;
+ if (!(errno = vfs_walk(fd_s->file->dnode,
+ pathname,
+ &dnode,
+ NULL,
+ VFS_WALK_NOFOLLOW))) {
+ errno = vfs_readlink(fd_s->file->dnode, buf, size);
+ }
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ if (dnode->inode->open_count) {
+ errno = EBUSY;
+ goto done;
+ }
+
+ if ((dnode->inode->itype & VFS_IFDIR)) {
+ errno = dnode->inode->ops.rmdir(dnode->inode);
+ } else {
+ errno = ENOTDIR;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+int
+__vfs_do_unlink(struct v_inode* inode)
+{
+ int errno;
+ if (inode->open_count) {
+ errno = EBUSY;
+ } else if (!(inode->itype & VFS_IFDIR)) {
+ // TODO handle symbolic link and type other than regular file
+ errno = inode->ops.unlink(inode);
+ if (!errno) {
+ inode->link_count--;
+ }
+ } else {
+ errno = EISDIR;
+ }
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL1(int, unlink, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ errno = __vfs_do_unlink(dnode->inode);
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int, unlinkat, int, fd, const char*, pathname)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ } else {
+ struct v_dnode* dnode;
+ if (!(errno = vfs_walk(fd_s->file->dnode, pathname, &dnode, NULL, 0))) {
+ errno = __vfs_do_unlink(dnode->inode);
+ }
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int, link, const char*, oldpath, const char*, newpath)
+{
+ int errno;
+ struct v_dnode *dentry, *to_link, *name_dentry, *name_file;
+
+ 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);
+ if (!errno) {
+ errno = EEXIST;
+ } else if (name_file) {
+ errno = vfs_link(to_link, name_file);
+ }
+ }
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, fsync, int, fildes)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if (!GET_FD(fildes, fd_s)) {
+ errno = EBADF;
+ } else {
+ errno = vfs_fsync(fd_s->file);
+ }
+
+ return DO_STATUS(errno);
+}
+
+int
+__vfs_dup_fd(struct v_fd* old, struct v_fd** new)
+{
+ int errno = 0;
+ struct v_fd* copied = cake_grab(fd_pile);
+
+ memcpy(copied, old, sizeof(struct v_fd));
+ old->file->ref_count++;
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL2(int, dup2, int, oldfd, int, newfd)
+{
+ if (newfd == oldfd) {
+ return newfd;
+ }
+
+ int errno;
+ struct v_fd *oldfd_s, *newfd_s;
+ if (!GET_FD(oldfd, oldfd_s) || TEST_FD(newfd)) {
+ errno = EBADF;
+ goto done;
+ }
+ newfd_s = __current->fdtable->fds[newfd];
+ if (newfd_s && (errno = vfs_close(newfd_s))) {
+ goto done;
+ }
+
+ if (!(errno = __vfs_dup_fd(oldfd_s, &newfd_s))) {
+ __current->fdtable->fds[newfd] = newfd_s;
+ return newfd;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, dup, int, oldfd)
+{
+ int errno, newfd;
+ struct v_fd *oldfd_s, *newfd_s;
+ if (!GET_FD(oldfd, oldfd_s)) {
+ errno = EBADF;
+ } else if (!(errno = vfs_alloc_fdslot(&newfd)) &&
+ !(errno = __vfs_dup_fd(oldfd_s, &newfd_s))) {
+ __current->fdtable->fds[newfd] = newfd_s;
+ return newfd;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int,
+ symlink,
+ const char*,
+ pathname,
+ const char*,
+ link_target)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+ if (!dnode->inode->ops.symlink) {
+ errno = ENOTSUP;
+ goto done;
+ }
+
+ errno = dnode->inode->ops.symlink(dnode->inode, link_target);
+
+done:
+ return DO_STATUS(errno);
git://scm.lunaixsky.com / lunaix-os.git / blobdiff