#ifndef __LUNAIX_VFS_H
#define __LUNAIX_VFS_H
-#include <lunaix/clock.h>
-#include <lunaix/device.h>
#include <lunaix/ds/btrie.h>
#include <lunaix/ds/hashtable.h>
#include <lunaix/ds/hstr.h>
#include <lunaix/ds/llist.h>
#include <lunaix/ds/lru.h>
#include <lunaix/ds/mutex.h>
+#include <lunaix/ds/rwlock.h>
+
+#include <lunaix/clock.h>
+#include <lunaix/device.h>
#include <lunaix/status.h>
#include <lunaix/spike.h>
#include <lunaix/bcache.h>
lru_use_one(dnode_lru, &dnode->lru); \
})
+#define dnode_atomic(dnode, ops) \
+ do { lock_dnode(dnode); ops; unlock_dnode(dnode); } while(0)
+
+#define locked_node(node) mutex_on_hold(&(node)->lock)
+
#define assert_fs(cond) assert_p(cond, "FS")
#define fail_fs(msg) fail_p(msg, "FS")
struct filesystem* fs;
};
+struct vncache
+{
+ struct hbucket* pool;
+ rwlock_t lock;
+};
+#define cache_atomic_read(cache, ops) \
+ do { \
+ rwlock_begin_read(&(cache)->lock); \
+ ops; \
+ rwlock_end_read(&(cache)->lock); \
+ } while (0)
+
+#define cache_atomic_write(cache, ops) \
+ do { \
+ rwlock_begin_write(&(cache)->lock); \
+ ops; \
+ rwlock_end_write(&(cache)->lock); \
+ } while (0)
+
+#define dnode_cache(dnode) (&(dnode)->super_block->d_cache)
+#define inode_cache(inode) (&(inode)->sb->i_cache)
+
struct v_superblock
{
struct llist_header sb_list;
struct v_dnode* root;
struct filesystem* fs;
struct blkbuf_cache* blks;
- struct hbucket* i_cache;
- struct hbucket* d_cache;
+ struct vncache i_cache;
+ struct vncache d_cache;
void* data;
unsigned int ref_count;
struct v_fdtable
{
struct v_fd* fds[VFS_MAX_FD];
+ mutex_t lock; // inter-threads contention
};
+#define lock_fdtable(fdtab) mutex_lock(&(fdtab)->lock)
+#define unlock_fdtable(fdtab) mutex_unlock(&(fdtab)->lock)
struct pcache
{
iterator->fs = NULL;
}
+void
+vfs_vncache_init(struct vncache* cache);
+
+void
+vfs_vncache_free(struct vncache* cache);
+
+void
+vfs_vncache_add(struct vncache* cache, size_t key, struct hlist_node* node);
+
+#define vncache_lock_read(cache) rwlock_begin_read(&(cache)->lock);
+#define vncache_unlock_read(cache) rwlock_end_read(&(cache)->lock);
+
+#define vncache_lock_write(cache) rwlock_begin_write(&(cache)->lock);
+#define vncache_unlock_write(cache) rwlock_end_write(&(cache)->lock);
+
void
vfs_init();
xattr_addcache(struct v_inode* inode, struct v_xattr_entry* xattr);
+/* --- fdtable --- */
+
+struct v_fdtable*
+fdtable_create();
+
+void
+fdtable_copy(struct v_fdtable* dest, struct v_fdtable* src);
+
+void
+fdtable_free(struct v_fdtable* table);
+
+
/* --- misc stuff --- */
#define check_itype(to_check, itype) \
vfs_sysroot->parent = vfs_sysroot;
vfs_ref_dnode(vfs_sysroot);
+ lru_remove(dnode_lru, &vfs_sysroot->lru);
+}
+
+void
+vfs_vncache_init(struct vncache* cache)
+{
+ cache->pool = vzalloc(VFS_HASHTABLE_SIZE * sizeof(struct hbucket));
+ rwlock_init(&cache->lock);
+}
+
+void
+vfs_vncache_free(struct vncache* cache)
+{
+ // clear all other reader/writer
+ rwlock_begin_write(&cache->lock);
+ vfree(cache->pool);
+
+ // already freed, so as the lock
+}
+
+void
+vfs_vncache_add(struct vncache* cache, size_t key, struct hlist_node* node)
+{
+ struct hbucket* slot;
+
+ cache_atomic_write(cache,
+ {
+ slot = &cache->pool[key & VFS_HASH_MASK];
+ hlist_delete(node);
+ hlist_add(&slot->head, node);
+ });
}
static inline struct hbucket*
-__dcache_hash(struct v_dnode* parent, u32_t* hash)
+__dcache_hash_nolock(struct v_dnode* parent, u32_t* hash)
{
+ struct v_superblock* sb;
struct hbucket* d_cache;
u32_t _hash;
+
+ sb = parent->super_block;
- d_cache = parent->super_block->d_cache;
_hash = *hash;
_hash = _hash ^ (_hash >> VFS_HASHBITS);
_hash += (u32_t)__ptr(parent);
*hash = _hash;
- return &d_cache[_hash & VFS_HASH_MASK];
+ return &sb->d_cache.pool[_hash & VFS_HASH_MASK];
}
static inline int
struct v_dnode*
vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str)
{
+ u32_t hash;
+ struct hbucket* slot;
+ struct v_dnode *pos, *n;
+ struct vncache *dcache;
+
if (!str->len || HSTR_EQ(str, &vfs_dot))
return parent;
return parent->parent;
}
- u32_t hash = str->hash;
- struct hbucket* slot = __dcache_hash(parent, &hash);
+ hash = str->hash;
+ dcache = dnode_cache(parent);
+
+ vncache_lock_read(dcache);
- struct v_dnode *pos, *n;
+ slot = __dcache_hash_nolock(parent, &hash);
hashtable_bucket_foreach(slot, pos, n, hash_list)
{
- if (pos->name.hash == hash && pos->parent == parent) {
- return pos;
+ if (pos->name.hash != hash || pos->parent != parent) {
+ continue;
}
+
+ vncache_unlock_read(dcache);
+ return pos;
}
+
+ vncache_unlock_read(dcache);
return NULL;
}
void
vfs_dcache_add(struct v_dnode* parent, struct v_dnode* dnode)
{
+ struct hbucket* bucket;
+ struct vncache* cache;
+
assert(parent);
+ assert(locked_node(parent));
dnode->ref_count = 1;
dnode->parent = parent;
llist_append(&parent->children, &dnode->siblings);
- struct hbucket* bucket = __dcache_hash(parent, &dnode->name.hash);
- hlist_add(&bucket->head, &dnode->hash_list);
+ cache_atomic_write(dnode_cache(parent),
+ {
+ bucket = __dcache_hash_nolock(parent, &dnode->name.hash);
+ hlist_add(&bucket->head, &dnode->hash_list);
+ });
}
void
llist_delete(&dnode->siblings);
llist_delete(&dnode->aka_list);
- hlist_delete(&dnode->hash_list);
+ lru_remove(dnode_lru, &dnode->lru);
+
+ cache_atomic_write(dnode_cache(dnode),
+ {
+ hlist_delete(&dnode->hash_list);
+ });
dnode->parent = NULL;
dnode->ref_count = 0;
vfs_dcache_rehash(struct v_dnode* new_parent, struct v_dnode* dnode)
{
assert(new_parent);
+ assert(locked_node(new_parent));
- hstr_rehash(&dnode->name, HSTR_FULL_HASH);
- vfs_dcache_remove(dnode);
- vfs_dcache_add(new_parent, dnode);
+ dnode_atomic(dnode,
+ {
+ hstr_rehash(&dnode->name, HSTR_FULL_HASH);
+ vfs_dcache_remove(dnode);
+ vfs_dcache_add(new_parent, dnode);
+ });
}
int
void
vfs_assign_inode(struct v_dnode* assign_to, struct v_inode* inode)
{
+ lock_dnode(assign_to);
+
if (assign_to->inode) {
llist_delete(&assign_to->aka_list);
assign_to->inode->link_count--;
llist_append(&inode->aka_dnodes, &assign_to->aka_list);
assign_to->inode = inode;
inode->link_count++;
+
+ unlock_dnode(assign_to);
}
int
vfs_link(struct v_dnode* to_link, struct v_dnode* name)
{
int errno;
+ struct v_inode* inode;
+
+ inode = to_link->inode;
if ((errno = vfs_check_writable(to_link))) {
return errno;
}
- lock_inode(to_link->inode);
+ lock_inode(inode);
+
if (to_link->super_block->root != name->super_block->root) {
errno = EXDEV;
- } else if (!to_link->inode->ops->link) {
+ } else if (!inode->ops->link) {
errno = ENOTSUP;
- } else if (!(errno = to_link->inode->ops->link(to_link->inode, name))) {
- vfs_assign_inode(name, to_link->inode);
+ } else if (!(errno = inode->ops->link(inode, name))) {
+ vfs_assign_inode(name, inode);
}
- unlock_inode(to_link->inode);
+
+ unlock_inode(inode);
return errno;
}
int
vfs_alloc_fdslot(int* fd)
{
+ struct v_fdtable* fdtab;
+
+ fdtab = __current->fdtable;
+ lock_fdtable(fdtab);
+
for (size_t i = 0; i < VFS_MAX_FD; i++) {
- if (!__current->fdtable->fds[i]) {
- *fd = i;
- return 0;
+ if (__current->fdtable->fds[i]) {
+ continue;
}
+
+ *fd = i;
+ unlock_fdtable(fdtab);
+ return 0;
}
+
+ unlock_fdtable(fdtab);
return EMFILE;
}
struct v_superblock* sb = cake_grab(superblock_pile);
memset(sb, 0, sizeof(*sb));
llist_init_head(&sb->sb_list);
-
- sb->i_cache = vzalloc(VFS_HASHTABLE_SIZE * sizeof(struct hbucket));
- sb->d_cache = vzalloc(VFS_HASHTABLE_SIZE * sizeof(struct hbucket));
+
+ vfs_vncache_init(&sb->i_cache);
+ vfs_vncache_init(&sb->d_cache);
sb->ref_count = 1;
return sb;
sb->ops.release(sb);
}
- vfree(sb->i_cache);
- vfree(sb->d_cache);
-
+ vfs_vncache_free(&sb->i_cache);
+ vfs_vncache_free(&sb->d_cache);
+
cake_release(superblock_pile, sb);
}
-static int
+static inline bool
+__dnode_evictable(struct v_dnode* dnode)
+{
+ return dnode->ref_count == 1
+ && llist_empty(&dnode->children);
+}
+
+static bool
__vfs_try_evict_dnode(struct lru_node* obj)
{
struct v_dnode* dnode = container_of(obj, struct v_dnode, lru);
- if (!dnode->ref_count) {
- vfs_d_free(dnode);
- return 1;
+ if (mutex_on_hold(&dnode->lock))
+ return false;
+
+ if (!__dnode_evictable(dnode)) {
+ return false;
}
- return 0;
+
+ vfs_d_free(dnode);
+ return true;
}
-static int
+static bool
__vfs_try_evict_inode(struct lru_node* obj)
{
struct v_inode* inode = container_of(obj, struct v_inode, lru);
vfs_d_free(struct v_dnode* dnode)
{
assert(dnode->ref_count == 1);
-
+
if (dnode->inode) {
assert(dnode->inode->link_count > 0);
dnode->inode->link_count--;
}
vfs_dcache_remove(dnode);
+
// Make sure the children de-referencing their parent.
// With lru presented, the eviction will be propagated over the entire
// detached subtree eventually
}
vfs_sb_unref(dnode->super_block);
+
vfree((void*)dnode->name.value);
cake_release(dnode_pile, dnode);
}
struct v_inode*
vfs_i_find(struct v_superblock* sb, u32_t i_id)
{
- struct hbucket* slot = &sb->i_cache[i_id & VFS_HASH_MASK];
- struct v_inode *pos, *n;
- hashtable_bucket_foreach(slot, pos, n, hash_list)
+ struct hbucket* slot;
+ struct v_inode *pos, *n, *found = NULL;
+
+ cache_atomic_read(&sb->i_cache,
{
- if (pos->id == i_id) {
+ slot = &sb->i_cache.pool[i_id & VFS_HASH_MASK];
+
+ hashtable_bucket_foreach(slot, pos, n, hash_list)
+ {
+ if (pos->id != i_id) {
+ continue;
+ }
+
lru_use_one(inode_lru, &pos->lru);
- return pos;
+ found = pos;
+ break;
}
- }
+ });
- return NULL;
+ return found;
}
void
vfs_i_addhash(struct v_inode* inode)
{
- struct hbucket* slot = &inode->sb->i_cache[inode->id & VFS_HASH_MASK];
-
- hlist_delete(&inode->hash_list);
- hlist_add(&slot->head, &inode->hash_list);
+ vfs_vncache_add(inode_cache(inode), inode->id, &inode->hash_list);
}
struct v_inode*
vfs_i_assign_sb(inode, sb);
lru_use_one(inode_lru, &inode->lru);
+
return inode;
}
pcache_release(inode->pg_cache);
vfree(inode->pg_cache);
}
+
// we don't need to sync inode.
// If an inode can be free, then it must be properly closed.
// Hence it must be synced already!
}
vfs_sb_unref(inode->sb);
+
hlist_delete(&inode->hash_list);
+ lru_remove(inode_lru, &inode->lru);
+
cake_release(inode_pile, inode);
}
int
vfs_getfd(int fd, struct v_fd** fd_s)
{
- if (TEST_FD(fd) && (*fd_s = __current->fdtable->fds[fd])) {
- return 0;
+ struct v_fdtable* fdtab;
+
+ if (!TEST_FD(fd)) {
+ return EBADF;
}
- return EBADF;
+
+ fdtab = __current->fdtable;
+
+ lock_fdtable(fdtab);
+ *fd_s = __current->fdtable->fds[fd];
+ unlock_fdtable(fdtab);
+
+ return !*fd_s ? EBADF : 0;
}
static int
if ((errno = fd_s->file->ops->readdir(fd_s->file, &dctx)) != 1) {
goto unlock;
}
+
dent->d_offset++;
fd_s->file->f_pos++;
return dtype;
}
+struct v_fdtable*
+fdtable_create()
+{
+ struct v_fdtable* fdtab;
+
+ fdtab = vzalloc(sizeof(struct v_fdtable));
+ mutex_init(&fdtab->lock);
+
+ return fdtab;
+}
+
+void
+fdtable_copy(struct v_fdtable* dest, struct v_fdtable* src)
+{
+ lock_fdtable(dest);
+ lock_fdtable(src);
+
+ for (size_t i = 0; i < VFS_MAX_FD; i++) {
+ struct v_fd* fd = src->fds[i];
+ if (!fd)
+ continue;
+ vfs_dup_fd(fd, &dest->fds[i]);
+ }
+
+ unlock_fdtable(dest);
+ unlock_fdtable(src);
+}
+
+void
+fdtable_free(struct v_fdtable* table)
+{
+ assert(!mutex_on_hold(&table->lock));
+
+ vfree(table);
+}
+
__DEFINE_LXSYSCALL3(int, realpathat, int, fd, char*, buf, size_t, size)
{
int errno;
}
struct v_dnode* dnode;
- errno = vfs_get_path(fd_s->file->dnode, buf, size, 0);
- if (errno >= 0) {
- return errno;
- }
+ dnode = fd_s->file->dnode;
+
+ lock_dnode(dnode);
+ errno = vfs_get_path(dnode, buf, size, 0);
+ unlock_dnode(dnode);
done:
return DO_STATUS(errno);
__DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
{
- int errno = 0;
+ int errno;
+ struct hstr name;
+ struct v_inode* inode;
struct v_dnode *parent, *dir;
char name_value[VFS_NAME_MAXLEN];
- struct hstr name = HHSTR(name_value, 0, 0);
+
+ name = HHSTR(name_value, 0, 0);
if ((errno = vfs_walk_proc(path, &parent, &name, VFS_WALK_PARENT))) {
goto done;
goto done;
}
- struct v_inode* inode = parent->inode;
+ inode = parent->inode;
lock_dnode(parent);
lock_inode(inode);
int
vfs_dup2(int oldfd, int newfd)
{
+ int errno;
+ struct v_fdtable* fdtab;
+ struct v_fd *oldfd_s, *newfd_s;
+
if (newfd == oldfd) {
return newfd;
}
- int errno;
- struct v_fd *oldfd_s, *newfd_s;
if ((errno = vfs_getfd(oldfd, &oldfd_s))) {
goto done;
}
goto done;
}
- newfd_s = __current->fdtable->fds[newfd];
+ fdtab = __current->fdtable;
+ lock_fdtable(fdtab);
+
+ newfd_s = fdtab->fds[newfd];
if (newfd_s && (errno = vfs_close(newfd_s->file))) {
- goto done;
+ goto unlock_and_done;
}
- if (!(errno = vfs_dup_fd(oldfd_s, &newfd_s))) {
- __current->fdtable->fds[newfd] = newfd_s;
- return newfd;
+ if ((errno = vfs_dup_fd(oldfd_s, &newfd_s))) {
+ goto unlock_and_done;
}
+ fdtab->fds[newfd] = newfd_s;
+
+ unlock_fdtable(fdtab);
+ return newfd;
+
+unlock_and_done:
+ unlock_fdtable(fdtab);
+
done:
return DO_STATUS(errno);
}
lock_dnode(current);
lock_dnode(target);
+
if (oldparent)
lock_dnode(oldparent);
if (newparent)
cleanup:
unlock_dnode(current);
+
if (oldparent)
unlock_dnode(oldparent);
if (newparent)
git://scm.lunaixsky.com / lunaix-os.git / commitdiff