#include <linux/list.h>
#include <linux/module.h>
#include <linux/ctype.h>
+#include <linux/string_helpers.h>
#include <asm/uaccess.h>
#include <linux/poll.h>
#include <linux/seq_file.h>
static bool cache_defer_req(struct cache_req *req, struct cache_head *item);
static void cache_revisit_request(struct cache_head *item);
-static void cache_init(struct cache_head *h)
+static void cache_init(struct cache_head *h, struct cache_detail *detail)
{
time_t now = seconds_since_boot();
- h->next = NULL;
+ INIT_HLIST_NODE(&h->cache_list);
h->flags = 0;
kref_init(&h->ref);
h->expiry_time = now + CACHE_NEW_EXPIRY;
+ if (now <= detail->flush_time)
+ /* ensure it isn't already expired */
+ now = detail->flush_time + 1;
h->last_refresh = now;
}
-static inline int cache_is_expired(struct cache_detail *detail, struct cache_head *h)
-{
- return (h->expiry_time < seconds_since_boot()) ||
- (detail->flush_time > h->last_refresh);
-}
-
struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
struct cache_head *key, int hash)
{
- struct cache_head **head, **hp;
- struct cache_head *new = NULL, *freeme = NULL;
+ struct cache_head *new = NULL, *freeme = NULL, *tmp = NULL;
+ struct hlist_head *head;
head = &detail->hash_table[hash];
read_lock(&detail->hash_lock);
- for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
- struct cache_head *tmp = *hp;
+ hlist_for_each_entry(tmp, head, cache_list) {
if (detail->match(tmp, key)) {
if (cache_is_expired(detail, tmp))
/* This entry is expired, we will discard it. */
* we might get lose if we need to
* cache_put it soon.
*/
- cache_init(new);
+ cache_init(new, detail);
detail->init(new, key);
write_lock(&detail->hash_lock);
/* check if entry appeared while we slept */
- for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
- struct cache_head *tmp = *hp;
+ hlist_for_each_entry(tmp, head, cache_list) {
if (detail->match(tmp, key)) {
if (cache_is_expired(detail, tmp)) {
- *hp = tmp->next;
- tmp->next = NULL;
+ hlist_del_init(&tmp->cache_list);
detail->entries --;
freeme = tmp;
break;
return tmp;
}
}
- new->next = *head;
- *head = new;
+
+ hlist_add_head(&new->cache_list, head);
detail->entries++;
cache_get(new);
write_unlock(&detail->hash_lock);
static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
-static void cache_fresh_locked(struct cache_head *head, time_t expiry)
+static void cache_fresh_locked(struct cache_head *head, time_t expiry,
+ struct cache_detail *detail)
{
+ time_t now = seconds_since_boot();
+ if (now <= detail->flush_time)
+ /* ensure it isn't immediately treated as expired */
+ now = detail->flush_time + 1;
head->expiry_time = expiry;
- head->last_refresh = seconds_since_boot();
+ head->last_refresh = now;
smp_wmb(); /* paired with smp_rmb() in cache_is_valid() */
set_bit(CACHE_VALID, &head->flags);
}
* If 'old' is not VALID, we update it directly,
* otherwise we need to replace it
*/
- struct cache_head **head;
struct cache_head *tmp;
if (!test_bit(CACHE_VALID, &old->flags)) {
set_bit(CACHE_NEGATIVE, &old->flags);
else
detail->update(old, new);
- cache_fresh_locked(old, new->expiry_time);
+ cache_fresh_locked(old, new->expiry_time, detail);
write_unlock(&detail->hash_lock);
cache_fresh_unlocked(old, detail);
return old;
cache_put(old, detail);
return NULL;
}
- cache_init(tmp);
+ cache_init(tmp, detail);
detail->init(tmp, old);
- head = &detail->hash_table[hash];
write_lock(&detail->hash_lock);
if (test_bit(CACHE_NEGATIVE, &new->flags))
set_bit(CACHE_NEGATIVE, &tmp->flags);
else
detail->update(tmp, new);
- tmp->next = *head;
- *head = tmp;
+ hlist_add_head(&tmp->cache_list, &detail->hash_table[hash]);
detail->entries++;
cache_get(tmp);
- cache_fresh_locked(tmp, new->expiry_time);
- cache_fresh_locked(old, 0);
+ cache_fresh_locked(tmp, new->expiry_time, detail);
+ cache_fresh_locked(old, 0, detail);
write_unlock(&detail->hash_lock);
cache_fresh_unlocked(tmp, detail);
cache_fresh_unlocked(old, detail);
return sunrpc_cache_pipe_upcall(cd, h);
}
-static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
+static inline int cache_is_valid(struct cache_head *h)
{
if (!test_bit(CACHE_VALID, &h->flags))
return -EAGAIN;
int rv;
write_lock(&detail->hash_lock);
- rv = cache_is_valid(detail, h);
- if (rv != -EAGAIN) {
- write_unlock(&detail->hash_lock);
- return rv;
+ rv = cache_is_valid(h);
+ if (rv == -EAGAIN) {
+ set_bit(CACHE_NEGATIVE, &h->flags);
+ cache_fresh_locked(h, seconds_since_boot()+CACHE_NEW_EXPIRY,
+ detail);
+ rv = -ENOENT;
}
- set_bit(CACHE_NEGATIVE, &h->flags);
- cache_fresh_locked(h, seconds_since_boot()+CACHE_NEW_EXPIRY);
write_unlock(&detail->hash_lock);
cache_fresh_unlocked(h, detail);
- return -ENOENT;
+ return rv;
}
/*
long refresh_age, age;
/* First decide return status as best we can */
- rv = cache_is_valid(detail, h);
+ rv = cache_is_valid(h);
/* now see if we want to start an upcall */
refresh_age = (h->expiry_time - h->last_refresh);
if (rqstp == NULL) {
if (rv == -EAGAIN)
rv = -ENOENT;
- } else if (rv == -EAGAIN || age > refresh_age/2) {
+ } else if (rv == -EAGAIN ||
+ (h->expiry_time != 0 && age > refresh_age/2)) {
dprintk("RPC: Want update, refage=%ld, age=%ld\n",
refresh_age, age);
if (!test_and_set_bit(CACHE_PENDING, &h->flags)) {
switch (cache_make_upcall(detail, h)) {
case -EINVAL:
- clear_bit(CACHE_PENDING, &h->flags);
- cache_revisit_request(h);
rv = try_to_negate_entry(detail, h);
break;
case -EAGAIN:
- clear_bit(CACHE_PENDING, &h->flags);
- cache_revisit_request(h);
+ cache_fresh_unlocked(h, detail);
break;
}
}
* Request was not deferred; handle it as best
* we can ourselves:
*/
- rv = cache_is_valid(detail, h);
+ rv = cache_is_valid(h);
if (rv == -EAGAIN)
rv = -ETIMEDOUT;
}
* a current pointer into that list and into the table
* for that entry.
*
- * Each time clean_cache is called it finds the next non-empty entry
+ * Each time cache_clean is called it finds the next non-empty entry
* in the current table and walks the list in that entry
* looking for entries that can be removed.
*
}
return;
out:
- printk(KERN_ERR "nfsd: failed to unregister %s cache\n", cd->name);
+ printk(KERN_ERR "RPC: failed to unregister %s cache\n", cd->name);
}
EXPORT_SYMBOL_GPL(sunrpc_destroy_cache_detail);
/* find a non-empty bucket in the table */
while (current_detail &&
current_index < current_detail->hash_size &&
- current_detail->hash_table[current_index] == NULL)
+ hlist_empty(¤t_detail->hash_table[current_index]))
current_index++;
/* find a cleanable entry in the bucket and clean it, or set to next bucket */
if (current_detail && current_index < current_detail->hash_size) {
- struct cache_head *ch, **cp;
+ struct cache_head *ch = NULL;
struct cache_detail *d;
+ struct hlist_head *head;
+ struct hlist_node *tmp;
write_lock(¤t_detail->hash_lock);
/* Ok, now to clean this strand */
- cp = & current_detail->hash_table[current_index];
- for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
+ head = ¤t_detail->hash_table[current_index];
+ hlist_for_each_entry_safe(ch, tmp, head, cache_list) {
if (current_detail->nextcheck > ch->expiry_time)
current_detail->nextcheck = ch->expiry_time+1;
if (!cache_is_expired(current_detail, ch))
continue;
- *cp = ch->next;
- ch->next = NULL;
+ hlist_del_init(&ch->cache_list);
current_detail->entries--;
rv = 1;
break;
current_index ++;
spin_unlock(&cache_list_lock);
if (ch) {
- if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
- cache_dequeue(current_detail, ch);
- cache_revisit_request(ch);
+ set_bit(CACHE_CLEANED, &ch->flags);
+ cache_fresh_unlocked(ch, d);
cache_put(ch, d);
}
} else
void cache_purge(struct cache_detail *detail)
{
- detail->flush_time = LONG_MAX;
+ time_t now = seconds_since_boot();
+ if (detail->flush_time >= now)
+ now = detail->flush_time + 1;
+ /* 'now' is the maximum value any 'last_refresh' can have */
+ detail->flush_time = now;
detail->nextcheck = seconds_since_boot();
cache_flush();
- detail->flush_time = 1;
}
EXPORT_SYMBOL_GPL(cache_purge);
/* Consider removing either the first or the last */
if (cache_defer_cnt > DFR_MAX) {
- if (net_random() & 1)
+ if (prandom_u32() & 1)
discard = list_entry(cache_defer_list.next,
struct cache_deferred_req, recent);
else
poll_wait(filp, &queue_wait, wait);
/* alway allow write */
- mask = POLL_OUT | POLLWRNORM;
+ mask = POLLOUT | POLLWRNORM;
if (!rp)
return mask;
static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
{
- struct cache_queue *cq;
+ struct cache_queue *cq, *tmp;
+ struct cache_request *cr;
+ struct list_head dequeued;
+
+ INIT_LIST_HEAD(&dequeued);
spin_lock(&queue_lock);
- list_for_each_entry(cq, &detail->queue, list)
+ list_for_each_entry_safe(cq, tmp, &detail->queue, list)
if (!cq->reader) {
- struct cache_request *cr = container_of(cq, struct cache_request, q);
+ cr = container_of(cq, struct cache_request, q);
if (cr->item != ch)
continue;
+ if (test_bit(CACHE_PENDING, &ch->flags))
+ /* Lost a race and it is pending again */
+ break;
if (cr->readers != 0)
continue;
- list_del(&cr->q.list);
- spin_unlock(&queue_lock);
- cache_put(cr->item, detail);
- kfree(cr->buf);
- kfree(cr);
- return;
+ list_move(&cr->q.list, &dequeued);
}
spin_unlock(&queue_lock);
+ while (!list_empty(&dequeued)) {
+ cr = list_entry(dequeued.next, struct cache_request, q.list);
+ list_del(&cr->q.list);
+ cache_put(cr->item, detail);
+ kfree(cr->buf);
+ kfree(cr);
+ }
}
/*
{
char *bp = *bpp;
int len = *lp;
- char c;
+ int ret;
if (len < 0) return;
- while ((c=*str++) && len)
- switch(c) {
- case ' ':
- case '\t':
- case '\n':
- case '\\':
- if (len >= 4) {
- *bp++ = '\\';
- *bp++ = '0' + ((c & 0300)>>6);
- *bp++ = '0' + ((c & 0070)>>3);
- *bp++ = '0' + ((c & 0007)>>0);
- }
- len -= 4;
- break;
- default:
- *bp++ = c;
- len--;
- }
- if (c || len <1) len = -1;
- else {
+ ret = string_escape_str(str, bp, len, ESCAPE_OCTAL, "\\ \n\t");
+ if (ret >= len) {
+ bp += len;
+ len = -1;
+ } else {
+ bp += ret;
+ len -= ret;
*bp++ = ' ';
len--;
}
*bp++ = 'x';
len -= 2;
while (blen && len >= 2) {
- unsigned char c = *buf++;
- *bp++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
- *bp++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
+ bp = hex_byte_pack(bp, *buf++);
len -= 2;
blen--;
}
char *buf;
struct cache_request *crq;
+ int ret = 0;
if (!detail->cache_request)
return -EINVAL;
warn_no_listener(detail);
return -EINVAL;
}
+ if (test_bit(CACHE_CLEANED, &h->flags))
+ /* Too late to make an upcall */
+ return -EAGAIN;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!buf)
crq->len = 0;
crq->readers = 0;
spin_lock(&queue_lock);
- list_add_tail(&crq->q.list, &detail->queue);
+ if (test_bit(CACHE_PENDING, &h->flags))
+ list_add_tail(&crq->q.list, &detail->queue);
+ else
+ /* Lost a race, no longer PENDING, so don't enqueue */
+ ret = -EAGAIN;
spin_unlock(&queue_lock);
wake_up(&queue_wait);
- return 0;
+ if (ret == -EAGAIN) {
+ kfree(buf);
+ kfree(crq);
+ }
+ return ret;
}
EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
if (bp[0] == '\\' && bp[1] == 'x') {
/* HEX STRING */
bp += 2;
- while (len < bufsize) {
+ while (len < bufsize - 1) {
int h, l;
h = hex_to_bin(bp[0]);
* get a header, then pass each real item in the cache
*/
-struct handle {
- struct cache_detail *cd;
-};
-
-static void *c_start(struct seq_file *m, loff_t *pos)
+void *cache_seq_start(struct seq_file *m, loff_t *pos)
__acquires(cd->hash_lock)
{
loff_t n = *pos;
unsigned int hash, entry;
struct cache_head *ch;
- struct cache_detail *cd = ((struct handle*)m->private)->cd;
-
+ struct cache_detail *cd = m->private;
read_lock(&cd->hash_lock);
if (!n--)
hash = n >> 32;
entry = n & ((1LL<<32) - 1);
- for (ch=cd->hash_table[hash]; ch; ch=ch->next)
+ hlist_for_each_entry(ch, &cd->hash_table[hash], cache_list)
if (!entry--)
return ch;
n &= ~((1LL<<32) - 1);
hash++;
n += 1LL<<32;
} while(hash < cd->hash_size &&
- cd->hash_table[hash]==NULL);
+ hlist_empty(&cd->hash_table[hash]));
if (hash >= cd->hash_size)
return NULL;
*pos = n+1;
- return cd->hash_table[hash];
+ return hlist_entry_safe(cd->hash_table[hash].first,
+ struct cache_head, cache_list);
}
+EXPORT_SYMBOL_GPL(cache_seq_start);
-static void *c_next(struct seq_file *m, void *p, loff_t *pos)
+void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos)
{
struct cache_head *ch = p;
int hash = (*pos >> 32);
- struct cache_detail *cd = ((struct handle*)m->private)->cd;
+ struct cache_detail *cd = m->private;
if (p == SEQ_START_TOKEN)
hash = 0;
- else if (ch->next == NULL) {
+ else if (ch->cache_list.next == NULL) {
hash++;
*pos += 1LL<<32;
} else {
++*pos;
- return ch->next;
+ return hlist_entry_safe(ch->cache_list.next,
+ struct cache_head, cache_list);
}
*pos &= ~((1LL<<32) - 1);
while (hash < cd->hash_size &&
- cd->hash_table[hash] == NULL) {
+ hlist_empty(&cd->hash_table[hash])) {
hash++;
*pos += 1LL<<32;
}
if (hash >= cd->hash_size)
return NULL;
++*pos;
- return cd->hash_table[hash];
+ return hlist_entry_safe(cd->hash_table[hash].first,
+ struct cache_head, cache_list);
}
+EXPORT_SYMBOL_GPL(cache_seq_next);
-static void c_stop(struct seq_file *m, void *p)
+void cache_seq_stop(struct seq_file *m, void *p)
__releases(cd->hash_lock)
{
- struct cache_detail *cd = ((struct handle*)m->private)->cd;
+ struct cache_detail *cd = m->private;
read_unlock(&cd->hash_lock);
}
+EXPORT_SYMBOL_GPL(cache_seq_stop);
static int c_show(struct seq_file *m, void *p)
{
struct cache_head *cp = p;
- struct cache_detail *cd = ((struct handle*)m->private)->cd;
+ struct cache_detail *cd = m->private;
if (p == SEQ_START_TOKEN)
return cd->cache_show(m, cd, NULL);
}
static const struct seq_operations cache_content_op = {
- .start = c_start,
- .next = c_next,
- .stop = c_stop,
+ .start = cache_seq_start,
+ .next = cache_seq_next,
+ .stop = cache_seq_stop,
.show = c_show,
};
static int content_open(struct inode *inode, struct file *file,
struct cache_detail *cd)
{
- struct handle *han;
+ struct seq_file *seq;
+ int err;
if (!cd || !try_module_get(cd->owner))
return -EACCES;
- han = __seq_open_private(file, &cache_content_op, sizeof(*han));
- if (han == NULL) {
+
+ err = seq_open(file, &cache_content_op);
+ if (err) {
module_put(cd->owner);
- return -ENOMEM;
+ return err;
}
- han->cd = cd;
+ seq = file->private_data;
+ seq->private = cd;
return 0;
}
static int content_release(struct inode *inode, struct file *file,
struct cache_detail *cd)
{
- int ret = seq_release_private(inode, file);
+ int ret = seq_release(inode, file);
module_put(cd->owner);
return ret;
}
{
char tbuf[20];
char *bp, *ep;
+ time_t then, now;
if (*ppos || count > sizeof(tbuf)-1)
return -EINVAL;
return -EINVAL;
bp = tbuf;
- cd->flush_time = get_expiry(&bp);
- cd->nextcheck = seconds_since_boot();
+ then = get_expiry(&bp);
+ now = seconds_since_boot();
+ cd->nextcheck = now;
+ /* Can only set flush_time to 1 second beyond "now", or
+ * possibly 1 second beyond flushtime. This is because
+ * flush_time never goes backwards so it mustn't get too far
+ * ahead of time.
+ */
+ if (then >= now) {
+ /* Want to flush everything, so behave like cache_purge() */
+ if (cd->flush_time >= now)
+ now = cd->flush_time + 1;
+ then = now;
+ }
+
+ cd->flush_time = then;
cache_flush();
*ppos += count;
struct cache_detail *cache_create_net(struct cache_detail *tmpl, struct net *net)
{
struct cache_detail *cd;
+ int i;
cd = kmemdup(tmpl, sizeof(struct cache_detail), GFP_KERNEL);
if (cd == NULL)
return ERR_PTR(-ENOMEM);
- cd->hash_table = kzalloc(cd->hash_size * sizeof(struct cache_head *),
+ cd->hash_table = kzalloc(cd->hash_size * sizeof(struct hlist_head),
GFP_KERNEL);
if (cd->hash_table == NULL) {
kfree(cd);
return ERR_PTR(-ENOMEM);
}
+
+ for (i = 0; i < cd->hash_size; i++)
+ INIT_HLIST_HEAD(&cd->hash_table[i]);
cd->net = net;
return cd;
}
const char *name, umode_t umode,
struct cache_detail *cd)
{
- struct qstr q;
- struct dentry *dir;
- int ret = 0;
-
- q.name = name;
- q.len = strlen(name);
- q.hash = full_name_hash(q.name, q.len);
- dir = rpc_create_cache_dir(parent, &q, umode, cd);
- if (!IS_ERR(dir))
- cd->u.pipefs.dir = dir;
- else
- ret = PTR_ERR(dir);
- return ret;
+ struct dentry *dir = rpc_create_cache_dir(parent, name, umode, cd);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+ cd->u.pipefs.dir = dir;
+ return 0;
}
EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
projects / firefly-linux-kernel-4.4.55.git / blobdiff