struct hstr vfs_ddot = HSTR("..", 2);
struct hstr vfs_dot = HSTR(".", 1);
+struct hstr vfs_empty = HSTR("", 0);
struct v_dnode*
vfs_d_alloc();
// 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();
+ root_sb->root->inode = vfs_i_alloc();
}
inline struct hbucket*
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;
}
int
-vfs_walk(struct v_dnode* start,
- const char* path,
- struct v_dnode** dentry,
- struct hstr* component,
- int walk_options)
+__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;
return ENAMETOOLONG;
}
if (!VFS_VALID_CHAR(current)) {
- return VFS_EINVLD;
+ return EINVAL;
}
name_content[j++] = current;
if (lookahead) {
if (!dnode) {
dnode = vfs_d_alloc();
- dnode->name = HSTR(valloc(VFS_NAME_MAXLEN), j);
- dnode->name.hash = name.hash;
+ dnode->name = HHSTR(valloc(VFS_NAME_MAXLEN), j, name.hash);
strcpy(dnode->name.value, name_content);
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;
+ char* pathname = path;
+ int errno = __vfs_walk(start, path, &interim, component, options);
+ int counter = 0;
+
+ while (!errno) {
+ if (counter >= VFS_MAX_SYMLINK) {
+ errno = ELOOP;
+ continue;
+ }
+ if ((interim->inode->itype & VFS_IFSYMLINK) &&
+ !(options & VFS_WALK_NOFOLLOW) &&
+ interim->inode->ops.read_symlink) {
+ errno = interim->inode->ops.read_symlink(interim->inode, &pathname);
+ if (errno) {
+ break;
+ }
+ } else {
+ break;
+ }
+ errno = __vfs_walk(start, pathname, &interim, component, options);
+ counter++;
+ }
+
+ *dentry = errno ? 0 : interim;
+
+ return errno;
+}
+
int
vfs_mount(const char* target, const char* fs_name, bdev_t device)
{
{
struct filesystem* fs = fsm_get(fs_name);
if (!fs)
- return VFS_ENOFS;
+ return ENODEV;
struct v_superblock* sb = vfs_sb_alloc();
sb->dev = device;
sb->fs_id = fs_id++;
int errno = 0;
struct v_superblock* sb = mnt_point->super_block;
if (!sb) {
- return VFS_EBADMNT;
+ return EINVAL;
}
if (!(errno = sb->fs->unmount(sb))) {
struct v_dnode* fs_root = sb->root;
return ENOTSUP;
}
+ struct v_inode* inode = dnode->inode;
struct v_file* vfile = cake_grab(file_pile);
memset(vfile, 0, sizeof(*vfile));
- int errno = dnode->inode->ops.open(dnode->inode, vfile);
+ vfile->dnode = dnode;
+ vfile->inode = inode;
+ vfile->ref_count = 1;
+ vfile->ops = inode->default_fops;
+ inode->open_count++;
+
+ if ((inode->itype & VFS_IFFILE) && !inode->pg_cache) {
+ struct pcache* pcache = vzalloc(sizeof(struct pcache));
+ pcache_init(pcache);
+ inode->pg_cache = pcache;
+ }
+
+ int errno = inode->ops.open(inode, vfile);
if (errno) {
cake_release(file_pile, vfile);
} else {
}
int
-vfs_close(struct v_file* file)
+vfs_link(struct v_dnode* to_link, struct v_dnode* name)
{
- if (!file->ops.close) {
- return ENOTSUP;
+ int errno;
+ if (to_link->super_block->root != name->super_block->root) {
+ errno = EXDEV;
+ } else if (!to_link->inode->ops.link) {
+ errno = ENOTSUP;
+ } else if (!(errno = to_link->inode->ops.link(to_link->inode, name))) {
+ name->inode = to_link->inode;
+ to_link->inode->link_count++;
}
- int errno = file->ops.close(file);
- if (!errno) {
+ return errno;
+}
+
+int
+vfs_close(struct v_file* file)
+{
+ int errno = 0;
+ if (!file->ops.close || !(errno = file->ops.close(file))) {
+ if (file->inode->open_count) {
+ file->inode->open_count--;
+ }
+ pcache_commit_all(file);
cake_release(file_pile, file);
}
return errno;
vfs_fsync(struct v_file* file)
{
int errno = ENOTSUP;
+ pcache_commit_all(file);
if (file->ops.sync) {
errno = file->ops.sync(file);
}
struct v_dnode* dnode = cake_grab(dnode_pile);
memset(dnode, 0, sizeof(*dnode));
llist_init_head(&dnode->children);
+ dnode->name = vfs_empty;
return dnode;
}
{
struct v_inode* inode = cake_grab(inode_pile);
memset(inode, 0, sizeof(*inode));
-
return 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_do_open(struct v_file** file_out, const char* path, int options)
+__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);
- struct v_dnode *dentry, *file;
int errno;
- if ((errno = vfs_walk(NULL, path, &dentry, &name, VFS_WALK_PARENT))) {
- return ENOENT;
+ if ((errno = vfs_walk(NULL, path, fdir, &name, VFS_WALK_PARENT))) {
+ return errno;
}
- vfs_walk(dentry, name.value, &file, NULL, 0);
+ errno = vfs_walk(*fdir, name.value, file, NULL, 0);
+ if (errno != ENOENT || !(options & FLOCATE_CREATE_EMPTY)) {
+ return errno;
+ }
- struct v_file* opened_file = 0;
- if (!file) {
- if ((options & FO_CREATE)) {
- errno = dentry->inode->ops.create(dentry->inode, opened_file);
- } else {
- errno = ENOENT;
- }
- } else {
- errno = vfs_open(file, &opened_file);
+ 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);
}
- *file_out = opened_file;
return errno;
}
-__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
+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)
{
- struct v_file* opened_file;
- int errno = __vfs_do_open(&opened_file, path, options), fd;
+ int errno, fd;
+ struct v_dnode *dentry, *file;
+ struct v_file* ofile = 0;
- __current->k_status = errno;
+ 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));
- fd_s->file = opened_file;
- fd_s->pos = opened_file->inode->fsize & -((options & FO_APPEND) != 0);
+ 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 SYSCALL_ESTATUS(errno);
+ 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 GET_FD(fd, fd_s) \
- (fd >= 0 && fd < VFS_MAX_FD && (fd_s = __current->fdtable->fds[fd]))
+#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;
+ int errno = 0;
if (!GET_FD(fd, fd_s)) {
errno = EBADF;
- } else if (!(errno = vfs_close(fd_s->file))) {
- vfree(fd_s);
- __current->fdtable->fds[fd] = 0;
+ goto done_err;
}
- __current->k_status = errno;
+ 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;
- return SYSCALL_ESTATUS(errno);
+done_err:
+ return DO_STATUS(errno);
}
void
int errno;
if (!GET_FD(fd, fd_s)) {
errno = EBADF;
- } else if (!(fd_s->file->inode->itype & VFS_INODE_TYPE_DIR)) {
+ } else if (!(fd_s->file->inode->itype & VFS_IFDIR)) {
errno = ENOTDIR;
} else {
struct dir_context dctx =
.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++;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+done:
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
errno = ENOTSUP;
} else if (!parent->inode->ops.mkdir) {
errno = ENOTSUP;
- } else if (!(parent->inode->itype & VFS_INODE_TYPE_DIR)) {
+ } else if (!(parent->inode->itype & VFS_IFDIR)) {
errno = ENOTDIR;
} else {
dir = vfs_d_alloc();
}
done:
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count)
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;
- }
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ cpu_enable_interrupt();
+ errno = file->ops.read(file, buf, count, file->f_pos);
+ cpu_disable_interrupt();
+
+ 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)
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;
- }
+ goto done;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
+ }
+
+ cpu_enable_interrupt();
+ errno = file->ops.write(file, buf, count, file->f_pos);
+ cpu_disable_interrupt();
+
+ if (errno > 0) {
+ file->f_pos += errno;
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
if (!GET_FD(fd, fd_s)) {
errno = EBADF;
} else {
- size_t fpos = fd_s->file->f_pos;
+ struct v_file* file = fd_s->file;
+ size_t fpos = file->f_pos;
switch (options) {
case FSEEK_CUR:
- fpos = (size_t)((int)fd_s->file->f_pos + offset);
+ fpos = (size_t)((int)file->f_pos + offset);
break;
case FSEEK_END:
- fpos = (size_t)((int)fd_s->file->inode->fsize + offset);
+ 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;
+ }
+ }
- default:
- break;
+ 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);
}
- fd_s->pos = fpos;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ 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);
}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff