#include <linux/fsnotify_backend.h>
#include <linux/fsnotify.h>
#include <linux/seq_file.h>
+ #include <linux/rhashtable.h>
#include "vfs.h"
#include "nfsd.h"
#include "filecache.h"
#include "trace.h"
- #define NFSDDBG_FACILITY NFSDDBG_FH
-
- /* FIXME: dynamically size this for the machine somehow? */
- #define NFSD_FILE_HASH_BITS 12
- #define NFSD_FILE_HASH_SIZE (1 << NFSD_FILE_HASH_BITS)
#define NFSD_LAUNDRETTE_DELAY (2 * HZ)
- #define NFSD_FILE_SHUTDOWN (1)
- #define NFSD_FILE_LRU_THRESHOLD (4096UL)
- #define NFSD_FILE_LRU_LIMIT (NFSD_FILE_LRU_THRESHOLD << 2)
+ #define NFSD_FILE_CACHE_UP (0)
/* We only care about NFSD_MAY_READ/WRITE for this cache */
#define NFSD_FILE_MAY_MASK (NFSD_MAY_READ|NFSD_MAY_WRITE)
- struct nfsd_fcache_bucket {
- struct hlist_head nfb_head;
- spinlock_t nfb_lock;
- unsigned int nfb_count;
- unsigned int nfb_maxcount;
- };
-
static DEFINE_PER_CPU(unsigned long, nfsd_file_cache_hits);
+ static DEFINE_PER_CPU(unsigned long, nfsd_file_acquisitions);
+ static DEFINE_PER_CPU(unsigned long, nfsd_file_releases);
+ static DEFINE_PER_CPU(unsigned long, nfsd_file_total_age);
+ static DEFINE_PER_CPU(unsigned long, nfsd_file_pages_flushed);
+ static DEFINE_PER_CPU(unsigned long, nfsd_file_evictions);
struct nfsd_fcache_disposal {
struct work_struct work;
static struct kmem_cache *nfsd_file_slab;
static struct kmem_cache *nfsd_file_mark_slab;
- static struct nfsd_fcache_bucket *nfsd_file_hashtbl;
static struct list_lru nfsd_file_lru;
- static long nfsd_file_lru_flags;
+ static unsigned long nfsd_file_flags;
static struct fsnotify_group *nfsd_file_fsnotify_group;
- static atomic_long_t nfsd_filecache_count;
static struct delayed_work nfsd_filecache_laundrette;
+ static struct rhashtable nfsd_file_rhash_tbl
+ ____cacheline_aligned_in_smp;
+
+ enum nfsd_file_lookup_type {
+ NFSD_FILE_KEY_INODE,
+ NFSD_FILE_KEY_FULL,
+ };
+
+ struct nfsd_file_lookup_key {
+ struct inode *inode;
+ struct net *net;
+ const struct cred *cred;
+ unsigned char need;
+ enum nfsd_file_lookup_type type;
+ };
+
+ /*
+ * The returned hash value is based solely on the address of an in-code
+ * inode, a pointer to a slab-allocated object. The entropy in such a
+ * pointer is concentrated in its middle bits.
+ */
+ static u32 nfsd_file_inode_hash(const struct inode *inode, u32 seed)
+ {
+ unsigned long ptr = (unsigned long)inode;
+ u32 k;
+
+ k = ptr >> L1_CACHE_SHIFT;
+ k &= 0x00ffffff;
+ return jhash2(&k, 1, seed);
+ }
+
+ /**
+ * nfsd_file_key_hashfn - Compute the hash value of a lookup key
+ * @data: key on which to compute the hash value
+ * @len: rhash table's key_len parameter (unused)
+ * @seed: rhash table's random seed of the day
+ *
+ * Return value:
+ * Computed 32-bit hash value
+ */
+ static u32 nfsd_file_key_hashfn(const void *data, u32 len, u32 seed)
+ {
+ const struct nfsd_file_lookup_key *key = data;
+
+ return nfsd_file_inode_hash(key->inode, seed);
+ }
+
+ /**
+ * nfsd_file_obj_hashfn - Compute the hash value of an nfsd_file
+ * @data: object on which to compute the hash value
+ * @len: rhash table's key_len parameter (unused)
+ * @seed: rhash table's random seed of the day
+ *
+ * Return value:
+ * Computed 32-bit hash value
+ */
+ static u32 nfsd_file_obj_hashfn(const void *data, u32 len, u32 seed)
+ {
+ const struct nfsd_file *nf = data;
+
+ return nfsd_file_inode_hash(nf->nf_inode, seed);
+ }
- static void nfsd_file_gc(void);
+ static bool
+ nfsd_match_cred(const struct cred *c1, const struct cred *c2)
+ {
+ int i;
+
+ if (!uid_eq(c1->fsuid, c2->fsuid))
+ return false;
+ if (!gid_eq(c1->fsgid, c2->fsgid))
+ return false;
+ if (c1->group_info == NULL || c2->group_info == NULL)
+ return c1->group_info == c2->group_info;
+ if (c1->group_info->ngroups != c2->group_info->ngroups)
+ return false;
+ for (i = 0; i < c1->group_info->ngroups; i++) {
+ if (!gid_eq(c1->group_info->gid[i], c2->group_info->gid[i]))
+ return false;
+ }
+ return true;
+ }
+
+ /**
+ * nfsd_file_obj_cmpfn - Match a cache item against search criteria
+ * @arg: search criteria
+ * @ptr: cache item to check
+ *
+ * Return values:
+ * %0 - Item matches search criteria
+ * %1 - Item does not match search criteria
+ */
+ static int nfsd_file_obj_cmpfn(struct rhashtable_compare_arg *arg,
+ const void *ptr)
+ {
+ const struct nfsd_file_lookup_key *key = arg->key;
+ const struct nfsd_file *nf = ptr;
+
+ switch (key->type) {
+ case NFSD_FILE_KEY_INODE:
+ if (nf->nf_inode != key->inode)
+ return 1;
+ break;
+ case NFSD_FILE_KEY_FULL:
+ if (nf->nf_inode != key->inode)
+ return 1;
+ if (nf->nf_may != key->need)
+ return 1;
+ if (nf->nf_net != key->net)
+ return 1;
+ if (!nfsd_match_cred(nf->nf_cred, key->cred))
+ return 1;
+ if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0)
+ return 1;
+ break;
+ }
+ return 0;
+ }
+
+ static const struct rhashtable_params nfsd_file_rhash_params = {
+ .key_len = sizeof_field(struct nfsd_file, nf_inode),
+ .key_offset = offsetof(struct nfsd_file, nf_inode),
+ .head_offset = offsetof(struct nfsd_file, nf_rhash),
+ .hashfn = nfsd_file_key_hashfn,
+ .obj_hashfn = nfsd_file_obj_hashfn,
+ .obj_cmpfn = nfsd_file_obj_cmpfn,
+ /* Reduce resizing churn on light workloads */
+ .min_size = 512, /* buckets */
+ .automatic_shrinking = true,
+ };
static void
nfsd_file_schedule_laundrette(void)
{
- long count = atomic_long_read(&nfsd_filecache_count);
-
- if (count == 0 || test_bit(NFSD_FILE_SHUTDOWN, &nfsd_file_lru_flags))
+ if ((atomic_read(&nfsd_file_rhash_tbl.nelems) == 0) ||
+ test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 0)
return;
queue_delayed_work(system_wq, &nfsd_filecache_laundrette,
}
static struct nfsd_file_mark *
- nfsd_file_mark_find_or_create(struct nfsd_file *nf)
+ nfsd_file_mark_find_or_create(struct nfsd_file *nf, struct inode *inode)
{
int err;
struct fsnotify_mark *mark;
struct nfsd_file_mark *nfm = NULL, *new;
- struct inode *inode = nf->nf_inode;
do {
fsnotify_group_lock(nfsd_file_fsnotify_group);
}
static struct nfsd_file *
- nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval,
- struct net *net)
+ nfsd_file_alloc(struct nfsd_file_lookup_key *key, unsigned int may)
{
struct nfsd_file *nf;
nf = kmem_cache_alloc(nfsd_file_slab, GFP_KERNEL);
if (nf) {
- INIT_HLIST_NODE(&nf->nf_node);
INIT_LIST_HEAD(&nf->nf_lru);
+ nf->nf_birthtime = ktime_get();
nf->nf_file = NULL;
nf->nf_cred = get_current_cred();
- nf->nf_net = net;
+ nf->nf_net = key->net;
nf->nf_flags = 0;
- nf->nf_inode = inode;
- nf->nf_hashval = hashval;
- refcount_set(&nf->nf_ref, 1);
- nf->nf_may = may & NFSD_FILE_MAY_MASK;
- if (may & NFSD_MAY_NOT_BREAK_LEASE) {
- if (may & NFSD_MAY_WRITE)
- __set_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags);
- if (may & NFSD_MAY_READ)
- __set_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags);
- }
+ __set_bit(NFSD_FILE_HASHED, &nf->nf_flags);
+ __set_bit(NFSD_FILE_PENDING, &nf->nf_flags);
+ nf->nf_inode = key->inode;
+ /* nf_ref is pre-incremented for hash table */
+ refcount_set(&nf->nf_ref, 2);
+ nf->nf_may = key->need;
nf->nf_mark = NULL;
- trace_nfsd_file_alloc(nf);
}
return nf;
}
static bool
nfsd_file_free(struct nfsd_file *nf)
{
+ s64 age = ktime_to_ms(ktime_sub(ktime_get(), nf->nf_birthtime));
bool flush = false;
+ this_cpu_inc(nfsd_file_releases);
+ this_cpu_add(nfsd_file_total_age, age);
+
trace_nfsd_file_put_final(nf);
if (nf->nf_mark)
nfsd_file_mark_put(nf->nf_mark);
fput(nf->nf_file);
flush = true;
}
+
+ /*
+ * If this item is still linked via nf_lru, that's a bug.
+ * WARN and leak it to preserve system stability.
+ */
+ if (WARN_ON_ONCE(!list_empty(&nf->nf_lru)))
+ return flush;
+
call_rcu(&nf->nf_rcu, nfsd_file_slab_free);
return flush;
}
static void
nfsd_file_flush(struct nfsd_file *nf)
{
- if (nf->nf_file && vfs_fsync(nf->nf_file, 1) != 0)
+ struct file *file = nf->nf_file;
+
+ if (!file || !(file->f_mode & FMODE_WRITE))
+ return;
+ this_cpu_add(nfsd_file_pages_flushed, file->f_mapping->nrpages);
+ if (vfs_fsync(file, 1) != 0)
nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
}
- static void
- nfsd_file_do_unhash(struct nfsd_file *nf)
+ static void nfsd_file_lru_add(struct nfsd_file *nf)
{
- lockdep_assert_held(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
+ set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);
+ if (list_lru_add(&nfsd_file_lru, &nf->nf_lru))
+ trace_nfsd_file_lru_add(nf);
+ }
+ static void nfsd_file_lru_remove(struct nfsd_file *nf)
+ {
+ if (list_lru_del(&nfsd_file_lru, &nf->nf_lru))
+ trace_nfsd_file_lru_del(nf);
+ }
+
+ static void
+ nfsd_file_hash_remove(struct nfsd_file *nf)
+ {
trace_nfsd_file_unhash(nf);
if (nfsd_file_check_write_error(nf))
nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
- --nfsd_file_hashtbl[nf->nf_hashval].nfb_count;
- hlist_del_rcu(&nf->nf_node);
- atomic_long_dec(&nfsd_filecache_count);
+ rhashtable_remove_fast(&nfsd_file_rhash_tbl, &nf->nf_rhash,
+ nfsd_file_rhash_params);
}
static bool
nfsd_file_unhash(struct nfsd_file *nf)
{
if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
- nfsd_file_do_unhash(nf);
- if (!list_empty(&nf->nf_lru))
- list_lru_del(&nfsd_file_lru, &nf->nf_lru);
+ nfsd_file_hash_remove(nf);
return true;
}
return false;
* Return true if the file was unhashed.
*/
static bool
- nfsd_file_unhash_and_release_locked(struct nfsd_file *nf, struct list_head *dispose)
+ nfsd_file_unhash_and_dispose(struct nfsd_file *nf, struct list_head *dispose)
{
- lockdep_assert_held(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
-
- trace_nfsd_file_unhash_and_release_locked(nf);
+ trace_nfsd_file_unhash_and_dispose(nf);
if (!nfsd_file_unhash(nf))
return false;
/* keep final reference for nfsd_file_lru_dispose */
if (refcount_dec_not_one(&nf->nf_ref))
return true;
+ nfsd_file_lru_remove(nf);
list_add(&nf->nf_lru, dispose);
return true;
}
if (refcount_dec_and_test(&nf->nf_ref)) {
WARN_ON(test_bit(NFSD_FILE_HASHED, &nf->nf_flags));
+ nfsd_file_lru_remove(nf);
nfsd_file_free(nf);
}
}
{
might_sleep();
- set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);
+ nfsd_file_lru_add(nf);
if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0) {
nfsd_file_flush(nf);
nfsd_file_put_noref(nf);
nfsd_file_schedule_laundrette();
} else
nfsd_file_put_noref(nf);
+ }
- if (atomic_long_read(&nfsd_filecache_count) >= NFSD_FILE_LRU_LIMIT)
- nfsd_file_gc();
+ /**
+ * nfsd_file_close - Close an nfsd_file
+ * @nf: nfsd_file to close
+ *
+ * If this is the final reference for @nf, free it immediately.
+ * This reflects an on-the-wire CLOSE or DELEGRETURN into the
+ * VFS and exported filesystem.
+ */
+ void nfsd_file_close(struct nfsd_file *nf)
+ {
+ nfsd_file_put(nf);
+ if (refcount_dec_if_one(&nf->nf_ref)) {
+ nfsd_file_unhash(nf);
+ nfsd_file_lru_remove(nf);
+ nfsd_file_free(nf);
+ }
}
struct nfsd_file *
while(!list_empty(dispose)) {
nf = list_first_entry(dispose, struct nfsd_file, nf_lru);
- list_del(&nf->nf_lru);
+ list_del_init(&nf->nf_lru);
nfsd_file_flush(nf);
nfsd_file_put_noref(nf);
}
while(!list_empty(dispose)) {
nf = list_first_entry(dispose, struct nfsd_file, nf_lru);
- list_del(&nf->nf_lru);
+ list_del_init(&nf->nf_lru);
nfsd_file_flush(nf);
if (!refcount_dec_and_test(&nf->nf_ref))
continue;
}
}
- /*
+ /**
+ * nfsd_file_lru_cb - Examine an entry on the LRU list
+ * @item: LRU entry to examine
+ * @lru: controlling LRU
+ * @lock: LRU list lock (unused)
+ * @arg: dispose list
+ *
* Note this can deadlock with nfsd_file_cache_purge.
+ *
+ * Return values:
+ * %LRU_REMOVED: @item was removed from the LRU
+ * %LRU_ROTATE: @item is to be moved to the LRU tail
+ * %LRU_SKIP: @item cannot be evicted
*/
static enum lru_status
nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru,
* counter. Here we check the counter and then test and clear the flag.
* That order is deliberate to ensure that we can do this locklessly.
*/
- if (refcount_read(&nf->nf_ref) > 1)
- goto out_skip;
+ if (refcount_read(&nf->nf_ref) > 1) {
+ list_lru_isolate(lru, &nf->nf_lru);
+ trace_nfsd_file_gc_in_use(nf);
+ return LRU_REMOVED;
+ }
/*
* Don't throw out files that are still undergoing I/O or
* that have uncleared errors pending.
*/
- if (nfsd_file_check_writeback(nf))
- goto out_skip;
+ if (nfsd_file_check_writeback(nf)) {
+ trace_nfsd_file_gc_writeback(nf);
+ return LRU_SKIP;
+ }
- if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags))
- goto out_skip;
+ if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags)) {
+ trace_nfsd_file_gc_referenced(nf);
+ return LRU_ROTATE;
+ }
- if (!test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags))
- goto out_skip;
+ if (!test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+ trace_nfsd_file_gc_hashed(nf);
+ return LRU_SKIP;
+ }
list_lru_isolate_move(lru, &nf->nf_lru, head);
+ this_cpu_inc(nfsd_file_evictions);
+ trace_nfsd_file_gc_disposed(nf);
return LRU_REMOVED;
- out_skip:
- return LRU_SKIP;
}
- static unsigned long
- nfsd_file_lru_walk_list(struct shrink_control *sc)
+ /*
+ * Unhash items on @dispose immediately, then queue them on the
+ * disposal workqueue to finish releasing them in the background.
+ *
+ * cel: Note that between the time list_lru_shrink_walk runs and
+ * now, these items are in the hash table but marked unhashed.
+ * Why release these outside of lru_cb ? There's no lock ordering
+ * problem since lru_cb currently takes no lock.
+ */
+ static void nfsd_file_gc_dispose_list(struct list_head *dispose)
{
- LIST_HEAD(head);
struct nfsd_file *nf;
- unsigned long ret;
- if (sc)
- ret = list_lru_shrink_walk(&nfsd_file_lru, sc,
- nfsd_file_lru_cb, &head);
- else
- ret = list_lru_walk(&nfsd_file_lru,
- nfsd_file_lru_cb,
- &head, LONG_MAX);
- list_for_each_entry(nf, &head, nf_lru) {
- spin_lock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
- nfsd_file_do_unhash(nf);
- spin_unlock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
- }
- nfsd_file_dispose_list_delayed(&head);
- return ret;
+ list_for_each_entry(nf, dispose, nf_lru)
+ nfsd_file_hash_remove(nf);
+ nfsd_file_dispose_list_delayed(dispose);
}
static void
nfsd_file_gc(void)
{
- nfsd_file_lru_walk_list(NULL);
+ LIST_HEAD(dispose);
+ unsigned long ret;
+
+ ret = list_lru_walk(&nfsd_file_lru, nfsd_file_lru_cb,
+ &dispose, list_lru_count(&nfsd_file_lru));
+ trace_nfsd_file_gc_removed(ret, list_lru_count(&nfsd_file_lru));
+ nfsd_file_gc_dispose_list(&dispose);
}
static void
static unsigned long
nfsd_file_lru_scan(struct shrinker *s, struct shrink_control *sc)
{
- return nfsd_file_lru_walk_list(sc);
+ LIST_HEAD(dispose);
+ unsigned long ret;
+
+ ret = list_lru_shrink_walk(&nfsd_file_lru, sc,
+ nfsd_file_lru_cb, &dispose);
+ trace_nfsd_file_shrinker_removed(ret, list_lru_count(&nfsd_file_lru));
+ nfsd_file_gc_dispose_list(&dispose);
+ return ret;
}
static struct shrinker nfsd_file_shrinker = {
.seeks = 1,
};
- static void
- __nfsd_file_close_inode(struct inode *inode, unsigned int hashval,
- struct list_head *dispose)
+ /*
+ * Find all cache items across all net namespaces that match @inode and
+ * move them to @dispose. The lookup is atomic wrt nfsd_file_acquire().
+ */
+ static unsigned int
+ __nfsd_file_close_inode(struct inode *inode, struct list_head *dispose)
{
- struct nfsd_file *nf;
- struct hlist_node *tmp;
+ struct nfsd_file_lookup_key key = {
+ .type = NFSD_FILE_KEY_INODE,
+ .inode = inode,
+ };
+ unsigned int count = 0;
+ struct nfsd_file *nf;
- spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock);
- hlist_for_each_entry_safe(nf, tmp, &nfsd_file_hashtbl[hashval].nfb_head, nf_node) {
- if (inode == nf->nf_inode)
- nfsd_file_unhash_and_release_locked(nf, dispose);
- }
- spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);
+ rcu_read_lock();
+ do {
+ nf = rhashtable_lookup(&nfsd_file_rhash_tbl, &key,
+ nfsd_file_rhash_params);
+ if (!nf)
+ break;
+ nfsd_file_unhash_and_dispose(nf, dispose);
+ count++;
+ } while (1);
+ rcu_read_unlock();
+ return count;
}
/**
* nfsd_file_close_inode_sync - attempt to forcibly close a nfsd_file
* @inode: inode of the file to attempt to remove
*
- * Walk the whole hash bucket, looking for any files that correspond to "inode".
- * If any do, then unhash them and put the hashtable reference to them and
- * destroy any that had their last reference put. Also ensure that any of the
- * fputs also have their final __fput done as well.
+ * Unhash and put, then flush and fput all cache items associated with @inode.
*/
void
nfsd_file_close_inode_sync(struct inode *inode)
{
- unsigned int hashval = (unsigned int)hash_long(inode->i_ino,
- NFSD_FILE_HASH_BITS);
LIST_HEAD(dispose);
+ unsigned int count;
- __nfsd_file_close_inode(inode, hashval, &dispose);
- trace_nfsd_file_close_inode_sync(inode, hashval, !list_empty(&dispose));
+ count = __nfsd_file_close_inode(inode, &dispose);
+ trace_nfsd_file_close_inode_sync(inode, count);
nfsd_file_dispose_list_sync(&dispose);
}
* nfsd_file_close_inode - attempt a delayed close of a nfsd_file
* @inode: inode of the file to attempt to remove
*
- * Walk the whole hash bucket, looking for any files that correspond to "inode".
- * If any do, then unhash them and put the hashtable reference to them and
- * destroy any that had their last reference put.
+ * Unhash and put all cache item associated with @inode.
*/
static void
nfsd_file_close_inode(struct inode *inode)
{
- unsigned int hashval = (unsigned int)hash_long(inode->i_ino,
- NFSD_FILE_HASH_BITS);
LIST_HEAD(dispose);
+ unsigned int count;
- __nfsd_file_close_inode(inode, hashval, &dispose);
- trace_nfsd_file_close_inode(inode, hashval, !list_empty(&dispose));
+ count = __nfsd_file_close_inode(inode, &dispose);
+ trace_nfsd_file_close_inode(inode, count);
nfsd_file_dispose_list_delayed(&dispose);
}
int
nfsd_file_cache_init(void)
{
- int ret = -ENOMEM;
- unsigned int i;
+ int ret;
- clear_bit(NFSD_FILE_SHUTDOWN, &nfsd_file_lru_flags);
-
- if (nfsd_file_hashtbl)
+ lockdep_assert_held(&nfsd_mutex);
+ if (test_and_set_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1)
return 0;
+ ret = rhashtable_init(&nfsd_file_rhash_tbl, &nfsd_file_rhash_params);
+ if (ret)
+ return ret;
+
+ ret = -ENOMEM;
nfsd_filecache_wq = alloc_workqueue("nfsd_filecache", 0, 0);
if (!nfsd_filecache_wq)
goto out;
- nfsd_file_hashtbl = kvcalloc(NFSD_FILE_HASH_SIZE,
- sizeof(*nfsd_file_hashtbl), GFP_KERNEL);
- if (!nfsd_file_hashtbl) {
- pr_err("nfsd: unable to allocate nfsd_file_hashtbl\n");
- goto out_err;
- }
-
nfsd_file_slab = kmem_cache_create("nfsd_file",
sizeof(struct nfsd_file), 0, 0, NULL);
if (!nfsd_file_slab) {
goto out_err;
}
- ret = register_shrinker(&nfsd_file_shrinker);
+ ret = register_shrinker(&nfsd_file_shrinker, "nfsd-filecache");
if (ret) {
pr_err("nfsd: failed to register nfsd_file_shrinker: %d\n", ret);
goto out_lru;
goto out_notifier;
}
- for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) {
- INIT_HLIST_HEAD(&nfsd_file_hashtbl[i].nfb_head);
- spin_lock_init(&nfsd_file_hashtbl[i].nfb_lock);
- }
-
INIT_DELAYED_WORK(&nfsd_filecache_laundrette, nfsd_file_gc_worker);
out:
return ret;
nfsd_file_slab = NULL;
kmem_cache_destroy(nfsd_file_mark_slab);
nfsd_file_mark_slab = NULL;
- kvfree(nfsd_file_hashtbl);
- nfsd_file_hashtbl = NULL;
destroy_workqueue(nfsd_filecache_wq);
nfsd_filecache_wq = NULL;
+ rhashtable_destroy(&nfsd_file_rhash_tbl);
goto out;
}
/*
* Note this can deadlock with nfsd_file_lru_cb.
*/
- void
- nfsd_file_cache_purge(struct net *net)
+ static void
+ __nfsd_file_cache_purge(struct net *net)
{
- unsigned int i;
- struct nfsd_file *nf;
- struct hlist_node *next;
+ struct rhashtable_iter iter;
+ struct nfsd_file *nf;
LIST_HEAD(dispose);
bool del;
- if (!nfsd_file_hashtbl)
- return;
-
- for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) {
- struct nfsd_fcache_bucket *nfb = &nfsd_file_hashtbl[i];
+ rhashtable_walk_enter(&nfsd_file_rhash_tbl, &iter);
+ do {
+ rhashtable_walk_start(&iter);
- spin_lock(&nfb->nfb_lock);
- hlist_for_each_entry_safe(nf, next, &nfb->nfb_head, nf_node) {
+ nf = rhashtable_walk_next(&iter);
+ while (!IS_ERR_OR_NULL(nf)) {
if (net && nf->nf_net != net)
continue;
- del = nfsd_file_unhash_and_release_locked(nf, &dispose);
+ del = nfsd_file_unhash_and_dispose(nf, &dispose);
/*
* Deadlock detected! Something marked this entry as
* unhased, but hasn't removed it from the hash list.
*/
WARN_ON_ONCE(!del);
+
+ nf = rhashtable_walk_next(&iter);
}
- spin_unlock(&nfb->nfb_lock);
- nfsd_file_dispose_list(&dispose);
- }
+
+ rhashtable_walk_stop(&iter);
+ } while (nf == ERR_PTR(-EAGAIN));
+ rhashtable_walk_exit(&iter);
+
+ nfsd_file_dispose_list(&dispose);
}
static struct nfsd_fcache_disposal *
return nn->fcache_disposal ? 0 : -ENOMEM;
}
+ /**
+ * nfsd_file_cache_purge - Remove all cache items associated with @net
+ * @net: target net namespace
+ *
+ */
+ void
+ nfsd_file_cache_purge(struct net *net)
+ {
+ lockdep_assert_held(&nfsd_mutex);
+ if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1)
+ __nfsd_file_cache_purge(net);
+ }
+
void
nfsd_file_cache_shutdown_net(struct net *net)
{
void
nfsd_file_cache_shutdown(void)
{
- set_bit(NFSD_FILE_SHUTDOWN, &nfsd_file_lru_flags);
+ int i;
+
+ lockdep_assert_held(&nfsd_mutex);
+ if (test_and_clear_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 0)
+ return;
lease_unregister_notifier(&nfsd_file_lease_notifier);
unregister_shrinker(&nfsd_file_shrinker);
* calling nfsd_file_cache_purge
*/
cancel_delayed_work_sync(&nfsd_filecache_laundrette);
- nfsd_file_cache_purge(NULL);
+ __nfsd_file_cache_purge(NULL);
list_lru_destroy(&nfsd_file_lru);
rcu_barrier();
fsnotify_put_group(nfsd_file_fsnotify_group);
fsnotify_wait_marks_destroyed();
kmem_cache_destroy(nfsd_file_mark_slab);
nfsd_file_mark_slab = NULL;
- kvfree(nfsd_file_hashtbl);
- nfsd_file_hashtbl = NULL;
destroy_workqueue(nfsd_filecache_wq);
nfsd_filecache_wq = NULL;
- }
-
- static bool
- nfsd_match_cred(const struct cred *c1, const struct cred *c2)
- {
- int i;
-
- if (!uid_eq(c1->fsuid, c2->fsuid))
- return false;
- if (!gid_eq(c1->fsgid, c2->fsgid))
- return false;
- if (c1->group_info == NULL || c2->group_info == NULL)
- return c1->group_info == c2->group_info;
- if (c1->group_info->ngroups != c2->group_info->ngroups)
- return false;
- for (i = 0; i < c1->group_info->ngroups; i++) {
- if (!gid_eq(c1->group_info->gid[i], c2->group_info->gid[i]))
- return false;
- }
- return true;
- }
-
- static struct nfsd_file *
- nfsd_file_find_locked(struct inode *inode, unsigned int may_flags,
- unsigned int hashval, struct net *net)
- {
- struct nfsd_file *nf;
- unsigned char need = may_flags & NFSD_FILE_MAY_MASK;
-
- hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head,
- nf_node, lockdep_is_held(&nfsd_file_hashtbl[hashval].nfb_lock)) {
- if (nf->nf_may != need)
- continue;
- if (nf->nf_inode != inode)
- continue;
- if (nf->nf_net != net)
- continue;
- if (!nfsd_match_cred(nf->nf_cred, current_cred()))
- continue;
- if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags))
- continue;
- if (nfsd_file_get(nf) != NULL)
- return nf;
+ rhashtable_destroy(&nfsd_file_rhash_tbl);
+
+ for_each_possible_cpu(i) {
+ per_cpu(nfsd_file_cache_hits, i) = 0;
+ per_cpu(nfsd_file_acquisitions, i) = 0;
+ per_cpu(nfsd_file_releases, i) = 0;
+ per_cpu(nfsd_file_total_age, i) = 0;
+ per_cpu(nfsd_file_pages_flushed, i) = 0;
+ per_cpu(nfsd_file_evictions, i) = 0;
}
- return NULL;
}
/**
- * nfsd_file_is_cached - are there any cached open files for this fh?
- * @inode: inode of the file to check
+ * nfsd_file_is_cached - are there any cached open files for this inode?
+ * @inode: inode to check
+ *
+ * The lookup matches inodes in all net namespaces and is atomic wrt
+ * nfsd_file_acquire().
*
- * Scan the hashtable for open files that match this fh. Returns true if there
- * are any, and false if not.
+ * Return values:
+ * %true: filecache contains at least one file matching this inode
+ * %false: filecache contains no files matching this inode
*/
bool
nfsd_file_is_cached(struct inode *inode)
{
- bool ret = false;
- struct nfsd_file *nf;
- unsigned int hashval;
-
- hashval = (unsigned int)hash_long(inode->i_ino, NFSD_FILE_HASH_BITS);
-
- rcu_read_lock();
- hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head,
- nf_node) {
- if (inode == nf->nf_inode) {
- ret = true;
- break;
- }
- }
- rcu_read_unlock();
- trace_nfsd_file_is_cached(inode, hashval, (int)ret);
+ struct nfsd_file_lookup_key key = {
+ .type = NFSD_FILE_KEY_INODE,
+ .inode = inode,
+ };
+ bool ret = false;
+
+ if (rhashtable_lookup_fast(&nfsd_file_rhash_tbl, &key,
+ nfsd_file_rhash_params) != NULL)
+ ret = true;
+ trace_nfsd_file_is_cached(inode, (int)ret);
return ret;
}
static __be32
- nfsd_do_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
+ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf, bool open)
{
- __be32 status;
- struct net *net = SVC_NET(rqstp);
+ struct nfsd_file_lookup_key key = {
+ .type = NFSD_FILE_KEY_FULL,
+ .need = may_flags & NFSD_FILE_MAY_MASK,
+ .net = SVC_NET(rqstp),
+ };
struct nfsd_file *nf, *new;
- struct inode *inode;
- unsigned int hashval;
bool retry = true;
+ __be32 status;
- /* FIXME: skip this if fh_dentry is already set? */
status = fh_verify(rqstp, fhp, S_IFREG,
may_flags|NFSD_MAY_OWNER_OVERRIDE);
if (status != nfs_ok)
return status;
+ key.inode = d_inode(fhp->fh_dentry);
+ key.cred = get_current_cred();
- inode = d_inode(fhp->fh_dentry);
- hashval = (unsigned int)hash_long(inode->i_ino, NFSD_FILE_HASH_BITS);
retry:
- rcu_read_lock();
- nf = nfsd_file_find_locked(inode, may_flags, hashval, net);
- rcu_read_unlock();
+ /* Avoid allocation if the item is already in cache */
+ nf = rhashtable_lookup_fast(&nfsd_file_rhash_tbl, &key,
+ nfsd_file_rhash_params);
+ if (nf)
+ nf = nfsd_file_get(nf);
if (nf)
goto wait_for_construction;
- new = nfsd_file_alloc(inode, may_flags, hashval, net);
+ new = nfsd_file_alloc(&key, may_flags);
if (!new) {
- trace_nfsd_file_acquire(rqstp, hashval, inode, may_flags,
- NULL, nfserr_jukebox);
- return nfserr_jukebox;
+ status = nfserr_jukebox;
+ goto out_status;
}
- spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock);
- nf = nfsd_file_find_locked(inode, may_flags, hashval, net);
- if (nf == NULL)
+ nf = rhashtable_lookup_get_insert_key(&nfsd_file_rhash_tbl,
+ &key, &new->nf_rhash,
+ nfsd_file_rhash_params);
+ if (!nf) {
+ nf = new;
goto open_file;
- spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);
+ }
+ if (IS_ERR(nf))
+ goto insert_err;
+ nf = nfsd_file_get(nf);
+ if (nf == NULL) {
+ nf = new;
+ goto open_file;
+ }
nfsd_file_slab_free(&new->nf_rcu);
wait_for_construction:
/* Did construction of this file fail? */
if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+ trace_nfsd_file_cons_err(rqstp, key.inode, may_flags, nf);
if (!retry) {
status = nfserr_jukebox;
goto out;
goto retry;
}
+ nfsd_file_lru_remove(nf);
this_cpu_inc(nfsd_file_cache_hits);
- if (!(may_flags & NFSD_MAY_NOT_BREAK_LEASE)) {
- bool write = (may_flags & NFSD_MAY_WRITE);
-
- if (test_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags) ||
- (test_bit(NFSD_FILE_BREAK_WRITE, &nf->nf_flags) && write)) {
- status = nfserrno(nfsd_open_break_lease(
- file_inode(nf->nf_file), may_flags));
- if (status == nfs_ok) {
- clear_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags);
- if (write)
- clear_bit(NFSD_FILE_BREAK_WRITE,
- &nf->nf_flags);
- }
- }
- }
+ status = nfserrno(nfsd_open_break_lease(file_inode(nf->nf_file), may_flags));
out:
if (status == nfs_ok) {
+ if (open)
+ this_cpu_inc(nfsd_file_acquisitions);
*pnf = nf;
} else {
nfsd_file_put(nf);
nf = NULL;
}
- trace_nfsd_file_acquire(rqstp, hashval, inode, may_flags, nf, status);
+ out_status:
+ put_cred(key.cred);
+ if (open)
+ trace_nfsd_file_acquire(rqstp, key.inode, may_flags, nf, status);
return status;
+
open_file:
- nf = new;
- /* Take reference for the hashtable */
- refcount_inc(&nf->nf_ref);
- __set_bit(NFSD_FILE_HASHED, &nf->nf_flags);
- __set_bit(NFSD_FILE_PENDING, &nf->nf_flags);
- list_lru_add(&nfsd_file_lru, &nf->nf_lru);
- hlist_add_head_rcu(&nf->nf_node, &nfsd_file_hashtbl[hashval].nfb_head);
- ++nfsd_file_hashtbl[hashval].nfb_count;
- nfsd_file_hashtbl[hashval].nfb_maxcount = max(nfsd_file_hashtbl[hashval].nfb_maxcount,
- nfsd_file_hashtbl[hashval].nfb_count);
- spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);
- if (atomic_long_inc_return(&nfsd_filecache_count) >= NFSD_FILE_LRU_THRESHOLD)
- nfsd_file_gc();
-
- nf->nf_mark = nfsd_file_mark_find_or_create(nf);
+ trace_nfsd_file_alloc(nf);
+ nf->nf_mark = nfsd_file_mark_find_or_create(nf, key.inode);
if (nf->nf_mark) {
if (open) {
status = nfsd_open_verified(rqstp, fhp, may_flags,
* If construction failed, or we raced with a call to unlink()
* then unhash.
*/
- if (status != nfs_ok || inode->i_nlink == 0) {
- bool do_free;
- spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock);
- do_free = nfsd_file_unhash(nf);
- spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);
- if (do_free)
+ if (status != nfs_ok || key.inode->i_nlink == 0)
+ if (nfsd_file_unhash(nf))
nfsd_file_put_noref(nf);
- }
clear_bit_unlock(NFSD_FILE_PENDING, &nf->nf_flags);
smp_mb__after_atomic();
wake_up_bit(&nf->nf_flags, NFSD_FILE_PENDING);
goto out;
+
+ insert_err:
+ nfsd_file_slab_free(&new->nf_rcu);
+ trace_nfsd_file_insert_err(rqstp, key.inode, may_flags, PTR_ERR(nf));
+ nf = NULL;
+ status = nfserr_jukebox;
+ goto out_status;
}
/**
nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf)
{
- return nfsd_do_file_acquire(rqstp, fhp, may_flags, pnf, true);
+ return nfsd_file_do_acquire(rqstp, fhp, may_flags, pnf, true);
}
/**
nfsd_file_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf)
{
- return nfsd_do_file_acquire(rqstp, fhp, may_flags, pnf, false);
+ return nfsd_file_do_acquire(rqstp, fhp, may_flags, pnf, false);
}
/*
*/
static int nfsd_file_cache_stats_show(struct seq_file *m, void *v)
{
- unsigned int i, count = 0, longest = 0;
- unsigned long hits = 0;
+ unsigned long releases = 0, pages_flushed = 0, evictions = 0;
+ unsigned long hits = 0, acquisitions = 0;
+ unsigned int i, count = 0, buckets = 0;
+ unsigned long lru = 0, total_age = 0;
- /*
- * No need for spinlocks here since we're not terribly interested in
- * accuracy. We do take the nfsd_mutex simply to ensure that we
- * don't end up racing with server shutdown
- */
+ /* Serialize with server shutdown */
mutex_lock(&nfsd_mutex);
- if (nfsd_file_hashtbl) {
- for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) {
- count += nfsd_file_hashtbl[i].nfb_count;
- longest = max(longest, nfsd_file_hashtbl[i].nfb_count);
- }
+ if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1) {
+ struct bucket_table *tbl;
+ struct rhashtable *ht;
+
+ lru = list_lru_count(&nfsd_file_lru);
+
+ rcu_read_lock();
+ ht = &nfsd_file_rhash_tbl;
+ count = atomic_read(&ht->nelems);
+ tbl = rht_dereference_rcu(ht->tbl, ht);
+ buckets = tbl->size;
+ rcu_read_unlock();
}
mutex_unlock(&nfsd_mutex);
- for_each_possible_cpu(i)
+ for_each_possible_cpu(i) {
hits += per_cpu(nfsd_file_cache_hits, i);
+ acquisitions += per_cpu(nfsd_file_acquisitions, i);
+ releases += per_cpu(nfsd_file_releases, i);
+ total_age += per_cpu(nfsd_file_total_age, i);
+ evictions += per_cpu(nfsd_file_evictions, i);
+ pages_flushed += per_cpu(nfsd_file_pages_flushed, i);
+ }
seq_printf(m, "total entries: %u\n", count);
- seq_printf(m, "longest chain: %u\n", longest);
+ seq_printf(m, "hash buckets: %u\n", buckets);
+ seq_printf(m, "lru entries: %lu\n", lru);
seq_printf(m, "cache hits: %lu\n", hits);
+ seq_printf(m, "acquisitions: %lu\n", acquisitions);
+ seq_printf(m, "releases: %lu\n", releases);
+ seq_printf(m, "evictions: %lu\n", evictions);
+ if (releases)
+ seq_printf(m, "mean age (ms): %ld\n", total_age / releases);
+ else
+ seq_printf(m, "mean age (ms): -\n");
+ seq_printf(m, "pages flushed: %lu\n", pages_flushed);
return 0;
}
projects / linux.git / commitdiff