static int fs_id = 0;
+struct hstr vfs_ddot = HSTR("..", 2);
+struct hstr vfs_dot = HSTR(".", 1);
+struct hstr vfs_empty = HSTR("", 0);
+
struct v_dnode*
vfs_d_alloc();
dnode_cache = vzalloc(DNODE_HASHTABLE_SIZE * sizeof(struct hbucket));
+ hstr_rehash(&vfs_ddot, HSTR_FULL_HASH);
+ hstr_rehash(&vfs_dot, HSTR_FULL_HASH);
+
// 创建一个根superblock，用来蕴含我们的根目录。
root_sb = vfs_sb_alloc();
root_sb->root = vfs_d_alloc();
struct v_dnode*
vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str)
{
- if (!str->len)
+ if (!str->len || HSTR_EQ(str, &vfs_dot))
return parent;
+ if (HSTR_EQ(str, &vfs_ddot)) {
+ return parent->parent ? parent->parent : parent;
+ }
+
struct hbucket* slot = __dcache_get_bucket(parent, str->hash);
struct v_dnode *pos, *n;
error:
vfree(dnode->name.value);
vfs_d_free(dnode);
+ *dentry = NULL;
return errno;
}
struct v_file* vfile = cake_grab(file_pile);
memset(vfile, 0, sizeof(*vfile));
+ vfile->dnode = dnode;
+ vfile->inode = dnode->inode;
+ dnode->inode->open_count++;
+
int errno = dnode->inode->ops.open(dnode->inode, vfile);
if (errno) {
cake_release(file_pile, vfile);
int errno = file->ops.close(file);
if (!errno) {
+ if (file->inode->open_count) {
+ file->inode->open_count--;
+ }
cake_release(file_pile, file);
}
return errno;
vfs_d_alloc()
{
struct v_dnode* dnode = cake_grab(dnode_pile);
+ memset(dnode, 0, sizeof(*dnode));
llist_init_head(&dnode->children);
+ dnode->name = vfs_empty;
+ return dnode;
}
void
cake_release(inode_pile, inode);
}
-__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
+/* ---- System call definition and support ---- */
+
+int
+__vfs_do_open(struct v_file** file_out, const char* path, int options)
{
char name_str[VFS_NAME_MAXLEN];
struct hstr name = HSTR(name_str, 0);
struct v_dnode *dentry, *file;
- int errno, fd;
+ int errno;
if ((errno = vfs_walk(NULL, path, &dentry, &name, VFS_WALK_PARENT))) {
- return -1;
+ return ENOENT;
}
vfs_walk(dentry, name.value, &file, NULL, 0);
errno = vfs_open(file, &opened_file);
}
- __current->k_status = errno;
+ *file_out = opened_file;
+ return errno;
+}
+
+__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
+{
+ struct v_file* opened_file;
+ int errno = __vfs_do_open(&opened_file, path, options), fd;
if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {
struct v_fd* fd_s = vzalloc(sizeof(*fd_s));
fd_s->file = opened_file;
- fd_s->pos = file->inode->fsize & -((options & FO_APPEND) == 0);
+ fd_s->pos = opened_file->inode->fsize & -((options & FO_APPEND) != 0);
__current->fdtable->fds[fd] = fd_s;
+ return fd;
}
+ __current->k_status = errno;
return SYSCALL_ESTATUS(errno);
}
+#define GET_FD(fd, fd_s) \
+ (fd >= 0 && fd < VFS_MAX_FD && (fd_s = __current->fdtable->fds[fd]))
+
__DEFINE_LXSYSCALL1(int, close, int, fd)
{
struct v_fd* fd_s;
int errno;
- if (fd < 0 || fd >= VFS_MAX_FD || !(fd_s = __current->fdtable->fds[fd])) {
+ if (!GET_FD(fd, fd_s)) {
errno = EBADF;
} else if (!(errno = vfs_close(fd_s->file))) {
vfree(fd_s);
{
struct v_fd* fd_s;
int errno;
- if (fd < 0 || fd >= VFS_MAX_FD || !(fd_s = __current->fdtable->fds[fd])) {
+ if (!GET_FD(fd, fd_s)) {
errno = EBADF;
} else if (!(fd_s->file->inode->itype & VFS_INODE_TYPE_DIR)) {
errno = ENOTDIR;
.index = dent->d_offset,
.read_complete_callback =
__vfs_readdir_callback };
- if (!(errno = fd_s->file->ops.readdir(fd_s->file, &dctx))) {
- dent->d_offset++;
+ 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:
__current->k_status = errno;
return SYSCALL_ESTATUS(errno);
}
goto done;
}
- if (!parent->inode->ops.mkdir) {
+ if ((parent->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = ENOTSUP;
+ } else if (!parent->inode->ops.mkdir) {
errno = ENOTSUP;
} else if (!(parent->inode->itype & VFS_INODE_TYPE_DIR)) {
errno = ENOTDIR;
return SYSCALL_ESTATUS(errno);
}
-__DEFINE_LXSYSCALL3(size_t, read, int, fd, void*, buf, size_t, count)
+__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;
+ } else {
+ struct v_file* file = fd_s->file;
+ file->f_pos = fd_s->pos;
+ if ((errno = file->ops.read(file, buf, count)) >= 0) {
+ fd_s->pos += errno;
+ }
+ }
+
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(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;
+ } else {
+ struct v_file* file = fd_s->file;
+ file->f_pos = fd_s->pos;
+ if ((errno = file->ops.write(file, buf, count)) >= 0) {
+ fd_s->pos += errno;
+ }
+ }
+
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
{
- // TODO
+ int errno = 0;
+ struct v_fd* fd_s;
+ if (!GET_FD(fd, fd_s)) {
+ errno = EBADF;
+ } else {
+ size_t fpos = fd_s->file->f_pos;
+ switch (options) {
+ case FSEEK_CUR:
+ fpos = (size_t)((int)fd_s->file->f_pos + offset);
+ break;
+ case FSEEK_END:
+ fpos = (size_t)((int)fd_s->file->inode->fsize + offset);
+ break;
+ case FSEEK_SET:
+ fpos = offset;
+ break;
+
+ default:
+ break;
+ }
+ fd_s->pos = fpos;
+ }
+
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(errno);
}
-__DEFINE_LXSYSCALL3(size_t, write, int, fd, void*, buf, size_t, count)
+int
+vfs_readlink(struct v_dnode* dnode, char* buf, size_t size, int depth)
{
- // TODO
+ if (!dnode) {
+ return 0;
+ }
+
+ if (depth > 64) {
+ return ELOOP;
+ }
+
+ size_t len = vfs_readlink(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;
+}
+
+__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, 0))) {
+ errno = vfs_readlink(dnode, buf, size, 0);
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(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, 0))) {
+ errno = vfs_readlink(fd_s->file->dnode, buf, size, 0);
+ }
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(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_INODE_TYPE_DIR) {
+ errno = dnode->inode->ops.rmdir(dnode->inode);
+ } else {
+ errno = ENOTDIR;
+ }
+
+done:
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(errno);
+}
+
+int
+__vfs_do_unlink(struct v_inode* inode)
+{
+ int errno;
+ if (inode->open_count) {
+ errno = EBUSY;
+ } else if (inode->itype != VFS_INODE_TYPE_DIR) {
+ // TODO handle symbolic link and type other than regular file
+ errno = inode->ops.unlink(inode);
+ } 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:
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(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:
+ __current->k_status = errno;
+ return SYSCALL_ESTATUS(errno);
}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff