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#include <kernel/malloc.h>
#include <kernel/panic.h>
#include <kernel/vfs/mount.h>
#include <shared/mem.h>
static VfsMount *mount_root = NULL;
VfsMount *vfs_mount_seed(void) {
return mount_root;
}
void vfs_root_register(const char *path, void (*accept)(VfsReq *)) {
VfsBackend *backend = kmalloc(sizeof *backend, "root bck");
VfsMount *mount = kmalloc(sizeof *mount, "root mnt");
*backend = (VfsBackend) {
.is_user = false,
.usehcnt = 1,
.kern.accept = accept,
};
*mount = (VfsMount){
.prev = mount_root,
.prefix = path,
.prefix_len = strlen(path),
.backend = backend,
.refs = 1,
};
mount_root = mount;
}
VfsMount *vfs_mount_resolve(
VfsMount *top, const char *path, size_t path_len)
{
for (; top; top = top->prev) {
if (top->prefix_len > path_len)
continue;
if (memcmp(top->prefix, path, top->prefix_len) != 0)
continue;
/* ensure that there's no garbage after the match
* e.g. don't recognize /thisasdf as mounted under /this */
if (top->prefix_len == path_len) // can't happen if prefix == path
break;
if (path[top->prefix_len] == '/')
break;
/* Also valid if prefix ends with '/'. Can only happen with kernel-
* provided mounts. */
if (top->prefix_len != 0 && path[top->prefix_len-1] == '/')
break;
}
return top;
}
void vfs_mount_remref(VfsMount *mnt) {
assert(mnt);
assert(mnt->refs > 0);
if (--(mnt->refs) > 0) return;
VfsMount *prev = mnt->prev;
if (mnt->backend) {
vfsback_userdown(mnt->backend);
}
if (mnt->prefix_owned) {
kfree((void*)mnt->prefix);
}
kfree(mnt);
if (prev) {
vfs_mount_remref(prev);
}
}
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