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path: root/fs/smb/server/vfs_cache.c
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-rw-r--r--fs/smb/server/vfs_cache.c706
1 files changed, 706 insertions, 0 deletions
diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c
new file mode 100644
index 000000000000..2d0138e72d78
--- /dev/null
+++ b/fs/smb/server/vfs_cache.c
@@ -0,0 +1,706 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
+ * Copyright (C) 2019 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/fs.h>
+#include <linux/filelock.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include "glob.h"
+#include "vfs_cache.h"
+#include "oplock.h"
+#include "vfs.h"
+#include "connection.h"
+#include "mgmt/tree_connect.h"
+#include "mgmt/user_session.h"
+#include "smb_common.h"
+
+#define S_DEL_PENDING 1
+#define S_DEL_ON_CLS 2
+#define S_DEL_ON_CLS_STREAM 8
+
+static unsigned int inode_hash_mask __read_mostly;
+static unsigned int inode_hash_shift __read_mostly;
+static struct hlist_head *inode_hashtable __read_mostly;
+static DEFINE_RWLOCK(inode_hash_lock);
+
+static struct ksmbd_file_table global_ft;
+static atomic_long_t fd_limit;
+static struct kmem_cache *filp_cache;
+
+void ksmbd_set_fd_limit(unsigned long limit)
+{
+ limit = min(limit, get_max_files());
+ atomic_long_set(&fd_limit, limit);
+}
+
+static bool fd_limit_depleted(void)
+{
+ long v = atomic_long_dec_return(&fd_limit);
+
+ if (v >= 0)
+ return false;
+ atomic_long_inc(&fd_limit);
+ return true;
+}
+
+static void fd_limit_close(void)
+{
+ atomic_long_inc(&fd_limit);
+}
+
+/*
+ * INODE hash
+ */
+
+static unsigned long inode_hash(struct super_block *sb, unsigned long hashval)
+{
+ unsigned long tmp;
+
+ tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) /
+ L1_CACHE_BYTES;
+ tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> inode_hash_shift);
+ return tmp & inode_hash_mask;
+}
+
+static struct ksmbd_inode *__ksmbd_inode_lookup(struct inode *inode)
+{
+ struct hlist_head *head = inode_hashtable +
+ inode_hash(inode->i_sb, inode->i_ino);
+ struct ksmbd_inode *ci = NULL, *ret_ci = NULL;
+
+ hlist_for_each_entry(ci, head, m_hash) {
+ if (ci->m_inode == inode) {
+ if (atomic_inc_not_zero(&ci->m_count))
+ ret_ci = ci;
+ break;
+ }
+ }
+ return ret_ci;
+}
+
+static struct ksmbd_inode *ksmbd_inode_lookup(struct ksmbd_file *fp)
+{
+ return __ksmbd_inode_lookup(file_inode(fp->filp));
+}
+
+static struct ksmbd_inode *ksmbd_inode_lookup_by_vfsinode(struct inode *inode)
+{
+ struct ksmbd_inode *ci;
+
+ read_lock(&inode_hash_lock);
+ ci = __ksmbd_inode_lookup(inode);
+ read_unlock(&inode_hash_lock);
+ return ci;
+}
+
+int ksmbd_query_inode_status(struct inode *inode)
+{
+ struct ksmbd_inode *ci;
+ int ret = KSMBD_INODE_STATUS_UNKNOWN;
+
+ read_lock(&inode_hash_lock);
+ ci = __ksmbd_inode_lookup(inode);
+ if (ci) {
+ ret = KSMBD_INODE_STATUS_OK;
+ if (ci->m_flags & S_DEL_PENDING)
+ ret = KSMBD_INODE_STATUS_PENDING_DELETE;
+ atomic_dec(&ci->m_count);
+ }
+ read_unlock(&inode_hash_lock);
+ return ret;
+}
+
+bool ksmbd_inode_pending_delete(struct ksmbd_file *fp)
+{
+ return (fp->f_ci->m_flags & S_DEL_PENDING);
+}
+
+void ksmbd_set_inode_pending_delete(struct ksmbd_file *fp)
+{
+ fp->f_ci->m_flags |= S_DEL_PENDING;
+}
+
+void ksmbd_clear_inode_pending_delete(struct ksmbd_file *fp)
+{
+ fp->f_ci->m_flags &= ~S_DEL_PENDING;
+}
+
+void ksmbd_fd_set_delete_on_close(struct ksmbd_file *fp,
+ int file_info)
+{
+ if (ksmbd_stream_fd(fp)) {
+ fp->f_ci->m_flags |= S_DEL_ON_CLS_STREAM;
+ return;
+ }
+
+ fp->f_ci->m_flags |= S_DEL_ON_CLS;
+}
+
+static void ksmbd_inode_hash(struct ksmbd_inode *ci)
+{
+ struct hlist_head *b = inode_hashtable +
+ inode_hash(ci->m_inode->i_sb, ci->m_inode->i_ino);
+
+ hlist_add_head(&ci->m_hash, b);
+}
+
+static void ksmbd_inode_unhash(struct ksmbd_inode *ci)
+{
+ write_lock(&inode_hash_lock);
+ hlist_del_init(&ci->m_hash);
+ write_unlock(&inode_hash_lock);
+}
+
+static int ksmbd_inode_init(struct ksmbd_inode *ci, struct ksmbd_file *fp)
+{
+ ci->m_inode = file_inode(fp->filp);
+ atomic_set(&ci->m_count, 1);
+ atomic_set(&ci->op_count, 0);
+ atomic_set(&ci->sop_count, 0);
+ ci->m_flags = 0;
+ ci->m_fattr = 0;
+ INIT_LIST_HEAD(&ci->m_fp_list);
+ INIT_LIST_HEAD(&ci->m_op_list);
+ rwlock_init(&ci->m_lock);
+ return 0;
+}
+
+static struct ksmbd_inode *ksmbd_inode_get(struct ksmbd_file *fp)
+{
+ struct ksmbd_inode *ci, *tmpci;
+ int rc;
+
+ read_lock(&inode_hash_lock);
+ ci = ksmbd_inode_lookup(fp);
+ read_unlock(&inode_hash_lock);
+ if (ci)
+ return ci;
+
+ ci = kmalloc(sizeof(struct ksmbd_inode), GFP_KERNEL);
+ if (!ci)
+ return NULL;
+
+ rc = ksmbd_inode_init(ci, fp);
+ if (rc) {
+ pr_err("inode initialized failed\n");
+ kfree(ci);
+ return NULL;
+ }
+
+ write_lock(&inode_hash_lock);
+ tmpci = ksmbd_inode_lookup(fp);
+ if (!tmpci) {
+ ksmbd_inode_hash(ci);
+ } else {
+ kfree(ci);
+ ci = tmpci;
+ }
+ write_unlock(&inode_hash_lock);
+ return ci;
+}
+
+static void ksmbd_inode_free(struct ksmbd_inode *ci)
+{
+ ksmbd_inode_unhash(ci);
+ kfree(ci);
+}
+
+static void ksmbd_inode_put(struct ksmbd_inode *ci)
+{
+ if (atomic_dec_and_test(&ci->m_count))
+ ksmbd_inode_free(ci);
+}
+
+int __init ksmbd_inode_hash_init(void)
+{
+ unsigned int loop;
+ unsigned long numentries = 16384;
+ unsigned long bucketsize = sizeof(struct hlist_head);
+ unsigned long size;
+
+ inode_hash_shift = ilog2(numentries);
+ inode_hash_mask = (1 << inode_hash_shift) - 1;
+
+ size = bucketsize << inode_hash_shift;
+
+ /* init master fp hash table */
+ inode_hashtable = vmalloc(size);
+ if (!inode_hashtable)
+ return -ENOMEM;
+
+ for (loop = 0; loop < (1U << inode_hash_shift); loop++)
+ INIT_HLIST_HEAD(&inode_hashtable[loop]);
+ return 0;
+}
+
+void ksmbd_release_inode_hash(void)
+{
+ vfree(inode_hashtable);
+}
+
+static void __ksmbd_inode_close(struct ksmbd_file *fp)
+{
+ struct ksmbd_inode *ci = fp->f_ci;
+ int err;
+ struct file *filp;
+
+ filp = fp->filp;
+ if (ksmbd_stream_fd(fp) && (ci->m_flags & S_DEL_ON_CLS_STREAM)) {
+ ci->m_flags &= ~S_DEL_ON_CLS_STREAM;
+ err = ksmbd_vfs_remove_xattr(file_mnt_idmap(filp),
+ filp->f_path.dentry,
+ fp->stream.name);
+ if (err)
+ pr_err("remove xattr failed : %s\n",
+ fp->stream.name);
+ }
+
+ if (atomic_dec_and_test(&ci->m_count)) {
+ write_lock(&ci->m_lock);
+ if (ci->m_flags & (S_DEL_ON_CLS | S_DEL_PENDING)) {
+ ci->m_flags &= ~(S_DEL_ON_CLS | S_DEL_PENDING);
+ write_unlock(&ci->m_lock);
+ ksmbd_vfs_unlink(filp);
+ write_lock(&ci->m_lock);
+ }
+ write_unlock(&ci->m_lock);
+
+ ksmbd_inode_free(ci);
+ }
+}
+
+static void __ksmbd_remove_durable_fd(struct ksmbd_file *fp)
+{
+ if (!has_file_id(fp->persistent_id))
+ return;
+
+ write_lock(&global_ft.lock);
+ idr_remove(global_ft.idr, fp->persistent_id);
+ write_unlock(&global_ft.lock);
+}
+
+static void __ksmbd_remove_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp)
+{
+ if (!has_file_id(fp->volatile_id))
+ return;
+
+ write_lock(&fp->f_ci->m_lock);
+ list_del_init(&fp->node);
+ write_unlock(&fp->f_ci->m_lock);
+
+ write_lock(&ft->lock);
+ idr_remove(ft->idr, fp->volatile_id);
+ write_unlock(&ft->lock);
+}
+
+static void __ksmbd_close_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp)
+{
+ struct file *filp;
+ struct ksmbd_lock *smb_lock, *tmp_lock;
+
+ fd_limit_close();
+ __ksmbd_remove_durable_fd(fp);
+ __ksmbd_remove_fd(ft, fp);
+
+ close_id_del_oplock(fp);
+ filp = fp->filp;
+
+ __ksmbd_inode_close(fp);
+ if (!IS_ERR_OR_NULL(filp))
+ fput(filp);
+
+ /* because the reference count of fp is 0, it is guaranteed that
+ * there are not accesses to fp->lock_list.
+ */
+ list_for_each_entry_safe(smb_lock, tmp_lock, &fp->lock_list, flist) {
+ spin_lock(&fp->conn->llist_lock);
+ list_del(&smb_lock->clist);
+ spin_unlock(&fp->conn->llist_lock);
+
+ list_del(&smb_lock->flist);
+ locks_free_lock(smb_lock->fl);
+ kfree(smb_lock);
+ }
+
+ if (ksmbd_stream_fd(fp))
+ kfree(fp->stream.name);
+ kmem_cache_free(filp_cache, fp);
+}
+
+static struct ksmbd_file *ksmbd_fp_get(struct ksmbd_file *fp)
+{
+ if (!atomic_inc_not_zero(&fp->refcount))
+ return NULL;
+ return fp;
+}
+
+static struct ksmbd_file *__ksmbd_lookup_fd(struct ksmbd_file_table *ft,
+ u64 id)
+{
+ struct ksmbd_file *fp;
+
+ if (!has_file_id(id))
+ return NULL;
+
+ read_lock(&ft->lock);
+ fp = idr_find(ft->idr, id);
+ if (fp)
+ fp = ksmbd_fp_get(fp);
+ read_unlock(&ft->lock);
+ return fp;
+}
+
+static void __put_fd_final(struct ksmbd_work *work, struct ksmbd_file *fp)
+{
+ __ksmbd_close_fd(&work->sess->file_table, fp);
+ atomic_dec(&work->conn->stats.open_files_count);
+}
+
+static void set_close_state_blocked_works(struct ksmbd_file *fp)
+{
+ struct ksmbd_work *cancel_work;
+
+ spin_lock(&fp->f_lock);
+ list_for_each_entry(cancel_work, &fp->blocked_works,
+ fp_entry) {
+ cancel_work->state = KSMBD_WORK_CLOSED;
+ cancel_work->cancel_fn(cancel_work->cancel_argv);
+ }
+ spin_unlock(&fp->f_lock);
+}
+
+int ksmbd_close_fd(struct ksmbd_work *work, u64 id)
+{
+ struct ksmbd_file *fp;
+ struct ksmbd_file_table *ft;
+
+ if (!has_file_id(id))
+ return 0;
+
+ ft = &work->sess->file_table;
+ read_lock(&ft->lock);
+ fp = idr_find(ft->idr, id);
+ if (fp) {
+ set_close_state_blocked_works(fp);
+
+ if (!atomic_dec_and_test(&fp->refcount))
+ fp = NULL;
+ }
+ read_unlock(&ft->lock);
+
+ if (!fp)
+ return -EINVAL;
+
+ __put_fd_final(work, fp);
+ return 0;
+}
+
+void ksmbd_fd_put(struct ksmbd_work *work, struct ksmbd_file *fp)
+{
+ if (!fp)
+ return;
+
+ if (!atomic_dec_and_test(&fp->refcount))
+ return;
+ __put_fd_final(work, fp);
+}
+
+static bool __sanity_check(struct ksmbd_tree_connect *tcon, struct ksmbd_file *fp)
+{
+ if (!fp)
+ return false;
+ if (fp->tcon != tcon)
+ return false;
+ return true;
+}
+
+struct ksmbd_file *ksmbd_lookup_foreign_fd(struct ksmbd_work *work, u64 id)
+{
+ return __ksmbd_lookup_fd(&work->sess->file_table, id);
+}
+
+struct ksmbd_file *ksmbd_lookup_fd_fast(struct ksmbd_work *work, u64 id)
+{
+ struct ksmbd_file *fp = __ksmbd_lookup_fd(&work->sess->file_table, id);
+
+ if (__sanity_check(work->tcon, fp))
+ return fp;
+
+ ksmbd_fd_put(work, fp);
+ return NULL;
+}
+
+struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id,
+ u64 pid)
+{
+ struct ksmbd_file *fp;
+
+ if (!has_file_id(id)) {
+ id = work->compound_fid;
+ pid = work->compound_pfid;
+ }
+
+ fp = __ksmbd_lookup_fd(&work->sess->file_table, id);
+ if (!__sanity_check(work->tcon, fp)) {
+ ksmbd_fd_put(work, fp);
+ return NULL;
+ }
+ if (fp->persistent_id != pid) {
+ ksmbd_fd_put(work, fp);
+ return NULL;
+ }
+ return fp;
+}
+
+struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id)
+{
+ return __ksmbd_lookup_fd(&global_ft, id);
+}
+
+struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid)
+{
+ struct ksmbd_file *fp = NULL;
+ unsigned int id;
+
+ read_lock(&global_ft.lock);
+ idr_for_each_entry(global_ft.idr, fp, id) {
+ if (!memcmp(fp->create_guid,
+ cguid,
+ SMB2_CREATE_GUID_SIZE)) {
+ fp = ksmbd_fp_get(fp);
+ break;
+ }
+ }
+ read_unlock(&global_ft.lock);
+
+ return fp;
+}
+
+struct ksmbd_file *ksmbd_lookup_fd_inode(struct inode *inode)
+{
+ struct ksmbd_file *lfp;
+ struct ksmbd_inode *ci;
+
+ ci = ksmbd_inode_lookup_by_vfsinode(inode);
+ if (!ci)
+ return NULL;
+
+ read_lock(&ci->m_lock);
+ list_for_each_entry(lfp, &ci->m_fp_list, node) {
+ if (inode == file_inode(lfp->filp)) {
+ atomic_dec(&ci->m_count);
+ lfp = ksmbd_fp_get(lfp);
+ read_unlock(&ci->m_lock);
+ return lfp;
+ }
+ }
+ atomic_dec(&ci->m_count);
+ read_unlock(&ci->m_lock);
+ return NULL;
+}
+
+#define OPEN_ID_TYPE_VOLATILE_ID (0)
+#define OPEN_ID_TYPE_PERSISTENT_ID (1)
+
+static void __open_id_set(struct ksmbd_file *fp, u64 id, int type)
+{
+ if (type == OPEN_ID_TYPE_VOLATILE_ID)
+ fp->volatile_id = id;
+ if (type == OPEN_ID_TYPE_PERSISTENT_ID)
+ fp->persistent_id = id;
+}
+
+static int __open_id(struct ksmbd_file_table *ft, struct ksmbd_file *fp,
+ int type)
+{
+ u64 id = 0;
+ int ret;
+
+ if (type == OPEN_ID_TYPE_VOLATILE_ID && fd_limit_depleted()) {
+ __open_id_set(fp, KSMBD_NO_FID, type);
+ return -EMFILE;
+ }
+
+ idr_preload(GFP_KERNEL);
+ write_lock(&ft->lock);
+ ret = idr_alloc_cyclic(ft->idr, fp, 0, INT_MAX - 1, GFP_NOWAIT);
+ if (ret >= 0) {
+ id = ret;
+ ret = 0;
+ } else {
+ id = KSMBD_NO_FID;
+ fd_limit_close();
+ }
+
+ __open_id_set(fp, id, type);
+ write_unlock(&ft->lock);
+ idr_preload_end();
+ return ret;
+}
+
+unsigned int ksmbd_open_durable_fd(struct ksmbd_file *fp)
+{
+ __open_id(&global_ft, fp, OPEN_ID_TYPE_PERSISTENT_ID);
+ return fp->persistent_id;
+}
+
+struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp)
+{
+ struct ksmbd_file *fp;
+ int ret;
+
+ fp = kmem_cache_zalloc(filp_cache, GFP_KERNEL);
+ if (!fp) {
+ pr_err("Failed to allocate memory\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ INIT_LIST_HEAD(&fp->blocked_works);
+ INIT_LIST_HEAD(&fp->node);
+ INIT_LIST_HEAD(&fp->lock_list);
+ spin_lock_init(&fp->f_lock);
+ atomic_set(&fp->refcount, 1);
+
+ fp->filp = filp;
+ fp->conn = work->conn;
+ fp->tcon = work->tcon;
+ fp->volatile_id = KSMBD_NO_FID;
+ fp->persistent_id = KSMBD_NO_FID;
+ fp->f_ci = ksmbd_inode_get(fp);
+
+ if (!fp->f_ci) {
+ ret = -ENOMEM;
+ goto err_out;
+ }
+
+ ret = __open_id(&work->sess->file_table, fp, OPEN_ID_TYPE_VOLATILE_ID);
+ if (ret) {
+ ksmbd_inode_put(fp->f_ci);
+ goto err_out;
+ }
+
+ atomic_inc(&work->conn->stats.open_files_count);
+ return fp;
+
+err_out:
+ kmem_cache_free(filp_cache, fp);
+ return ERR_PTR(ret);
+}
+
+static int
+__close_file_table_ids(struct ksmbd_file_table *ft,
+ struct ksmbd_tree_connect *tcon,
+ bool (*skip)(struct ksmbd_tree_connect *tcon,
+ struct ksmbd_file *fp))
+{
+ unsigned int id;
+ struct ksmbd_file *fp;
+ int num = 0;
+
+ idr_for_each_entry(ft->idr, fp, id) {
+ if (skip(tcon, fp))
+ continue;
+
+ set_close_state_blocked_works(fp);
+
+ if (!atomic_dec_and_test(&fp->refcount))
+ continue;
+ __ksmbd_close_fd(ft, fp);
+ num++;
+ }
+ return num;
+}
+
+static bool tree_conn_fd_check(struct ksmbd_tree_connect *tcon,
+ struct ksmbd_file *fp)
+{
+ return fp->tcon != tcon;
+}
+
+static bool session_fd_check(struct ksmbd_tree_connect *tcon,
+ struct ksmbd_file *fp)
+{
+ return false;
+}
+
+void ksmbd_close_tree_conn_fds(struct ksmbd_work *work)
+{
+ int num = __close_file_table_ids(&work->sess->file_table,
+ work->tcon,
+ tree_conn_fd_check);
+
+ atomic_sub(num, &work->conn->stats.open_files_count);
+}
+
+void ksmbd_close_session_fds(struct ksmbd_work *work)
+{
+ int num = __close_file_table_ids(&work->sess->file_table,
+ work->tcon,
+ session_fd_check);
+
+ atomic_sub(num, &work->conn->stats.open_files_count);
+}
+
+int ksmbd_init_global_file_table(void)
+{
+ return ksmbd_init_file_table(&global_ft);
+}
+
+void ksmbd_free_global_file_table(void)
+{
+ struct ksmbd_file *fp = NULL;
+ unsigned int id;
+
+ idr_for_each_entry(global_ft.idr, fp, id) {
+ __ksmbd_remove_durable_fd(fp);
+ kmem_cache_free(filp_cache, fp);
+ }
+
+ ksmbd_destroy_file_table(&global_ft);
+}
+
+int ksmbd_init_file_table(struct ksmbd_file_table *ft)
+{
+ ft->idr = kzalloc(sizeof(struct idr), GFP_KERNEL);
+ if (!ft->idr)
+ return -ENOMEM;
+
+ idr_init(ft->idr);
+ rwlock_init(&ft->lock);
+ return 0;
+}
+
+void ksmbd_destroy_file_table(struct ksmbd_file_table *ft)
+{
+ if (!ft->idr)
+ return;
+
+ __close_file_table_ids(ft, NULL, session_fd_check);
+ idr_destroy(ft->idr);
+ kfree(ft->idr);
+ ft->idr = NULL;
+}
+
+int ksmbd_init_file_cache(void)
+{
+ filp_cache = kmem_cache_create("ksmbd_file_cache",
+ sizeof(struct ksmbd_file), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!filp_cache)
+ goto out;
+
+ return 0;
+
+out:
+ pr_err("failed to allocate file cache\n");
+ return -ENOMEM;
+}
+
+void ksmbd_exit_file_cache(void)
+{
+ kmem_cache_destroy(filp_cache);
+}