+#include <lunaix/fs.h>
+#include <lunaix/mm/valloc.h>
+#include <lunaix/process.h>
+#include <lunaix/types.h>
+
+static struct llist_header all_mnts = { .next = &all_mnts, .prev = &all_mnts };
+
+struct v_mount*
+vfs_create_mount(struct v_mount* parent, struct v_dnode* mnt_point)
+{
+ struct v_mount* mnt = vzalloc(sizeof(struct v_mount));
+ if (!mnt) {
+ return NULL;
+ }
+
+ llist_init_head(&mnt->submnts);
+ llist_append(&all_mnts, &mnt->list);
+ mutex_init(&mnt->lock);
+
+ mnt_mkbusy(parent);
+ mnt->parent = parent;
+ mnt->mnt_point = mnt_point;
+ mnt->super_block = mnt_point->super_block;
+
+ if (parent) {
+ mutex_lock(&mnt->parent->lock);
+ llist_append(&parent->submnts, &mnt->sibmnts);
+ mutex_unlock(&mnt->parent->lock);
+ }
+
+ atomic_fetch_add(&mnt_point->ref_count, 1);
+
+ return mnt;
+}
+
+int
+__vfs_do_unmount(struct v_mount* mnt)
+{
+ int errno = 0;
+ struct v_superblock* sb = mnt->super_block;
+
+ if ((errno = sb->fs->unmount(sb))) {
+ return errno;
+ }
+
+ llist_delete(&mnt->list);
+ llist_delete(&mnt->sibmnts);
+
+ // detached the inodes from cache, and let lru policy to recycle them
+ for (size_t i = 0; i < VFS_HASHTABLE_SIZE; i++) {
+ struct hbucket* bucket = &sb->i_cache[i];
+ if (!bucket) {
+ continue;
+ }
+ bucket->head->pprev = 0;
+ }
+
+ mnt_chillax(mnt->parent);
+
+ vfs_sb_free(sb);
+ vfs_d_free(mnt->mnt_point);
+ vfree(mnt);
+
+ return errno;
+}
+
+void
+mnt_mkbusy(struct v_mount* mnt)
+{
+ while (mnt) {
+ mutex_lock(&mnt->lock);
+ mnt->busy_counter++;
+ mutex_unlock(&mnt->lock);
+
+ mnt = mnt->parent;
+ }
+}
+
+void
+mnt_chillax(struct v_mount* mnt)
+{
+ while (mnt) {
+ mutex_lock(&mnt->lock);
+ mnt->busy_counter--;
+ mutex_unlock(&mnt->lock);
+
+ mnt = mnt->parent;
+ }
+}
+
+int
+vfs_mount(const char* target, const char* fs_name, struct device* device)
+{
+ int errno;
+ struct v_dnode* mnt;
+
+ if (!(errno = vfs_walk(__current->cwd, target, &mnt, NULL, 0))) {
+ errno = vfs_mount_at(fs_name, device, mnt);
+ }
+
+ return errno;
+}
+
+int
+vfs_unmount(const char* target)
+{
+ int errno;
+ struct v_dnode* mnt;
+
+ if (!(errno = vfs_walk(__current->cwd, target, &mnt, NULL, 0))) {
+ errno = vfs_unmount_at(mnt);
+ }
+
+ return errno;
+}
+
+int
+vfs_mount_at(const char* fs_name,
+ struct device* device,
+ struct v_dnode* mnt_point)
+{
+ if (mnt_point->inode && !(mnt_point->inode->itype & VFS_IFDIR)) {
+ return ENOTDIR;
+ }
+
+ struct filesystem* fs = fsm_get(fs_name);
+ if (!fs) {
+ return ENODEV;
+ }
+
+ struct v_mount* parent_mnt = mnt_point->mnt;
+ struct v_superblock* sb = vfs_sb_alloc();
+ sb->dev = device;
+
+ int errno = 0;
+ if (!(errno = fs->mount(sb, mnt_point))) {
+ sb->fs = fs;
+ sb->root = mnt_point;
+ mnt_point->super_block = sb;
+
+ if (!(mnt_point->mnt = vfs_create_mount(parent_mnt, mnt_point))) {
+ errno = ENOMEM;
+ vfs_sb_free(sb);
+ }
+ }
+
+ return errno;
+}
+
+int
+vfs_unmount_at(struct v_dnode* mnt_point)
+{
+ int errno = 0;
+ struct v_superblock* sb = mnt_point->super_block;
+ if (!sb) {
+ return EINVAL;
+ }
+
+ if (sb->root != mnt_point) {
+ return EINVAL;
+ }
+
+ if (mnt_point->mnt->busy_counter) {
+ return EBUSY;
+ }
+
+ if (!(errno = __vfs_do_unmount(mnt_point->mnt))) {
+ atomic_fetch_sub(&mnt_point->ref_count, 1);
+ }
+
+ return errno;
+}
git://scm.lunaixsky.com / lunaix-os.git / commitdiff