diff options
Diffstat (limited to 'net/sunrpc/cache.c')
| -rw-r--r-- | net/sunrpc/cache.c | 276 |
1 files changed, 152 insertions, 124 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 72ad836e4fe..06636214113 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -50,12 +50,6 @@ static void cache_init(struct cache_head *h) 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) { @@ -196,12 +190,12 @@ EXPORT_SYMBOL_GPL(sunrpc_cache_update); static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h) { - if (!cd->cache_upcall) - return -EINVAL; - return cd->cache_upcall(cd, h); + if (cd->cache_upcall) + return cd->cache_upcall(cd, h); + 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; @@ -227,16 +221,15 @@ static int try_to_negate_entry(struct cache_detail *detail, struct cache_head *h 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); + 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; } /* @@ -260,7 +253,7 @@ int cache_check(struct cache_detail *detail, 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); @@ -269,19 +262,17 @@ int cache_check(struct cache_detail *detail, 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; } } @@ -293,7 +284,7 @@ int cache_check(struct cache_detail *detail, * 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; } @@ -310,7 +301,7 @@ EXPORT_SYMBOL_GPL(cache_check); * 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. * @@ -344,7 +335,7 @@ static int current_index; static void do_cache_clean(struct work_struct *work); static struct delayed_work cache_cleaner; -static void sunrpc_init_cache_detail(struct cache_detail *cd) +void sunrpc_init_cache_detail(struct cache_detail *cd) { rwlock_init(&cd->hash_lock); INIT_LIST_HEAD(&cd->queue); @@ -360,8 +351,9 @@ static void sunrpc_init_cache_detail(struct cache_detail *cd) /* start the cleaning process */ schedule_delayed_work(&cache_cleaner, 0); } +EXPORT_SYMBOL_GPL(sunrpc_init_cache_detail); -static void sunrpc_destroy_cache_detail(struct cache_detail *cd) +void sunrpc_destroy_cache_detail(struct cache_detail *cd) { cache_purge(cd); spin_lock(&cache_list_lock); @@ -382,8 +374,9 @@ static void sunrpc_destroy_cache_detail(struct cache_detail *cd) } 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); /* clean cache tries to find something to clean * and cleans it. @@ -455,9 +448,8 @@ static int cache_clean(void) 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 @@ -627,7 +619,7 @@ static void cache_limit_defers(void) /* 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 @@ -668,13 +660,13 @@ static void cache_revisit_request(struct cache_head *item) { struct cache_deferred_req *dreq; struct list_head pending; - struct hlist_node *lp, *tmp; + struct hlist_node *tmp; int hash = DFR_HASH(item); INIT_LIST_HEAD(&pending); spin_lock(&cache_defer_lock); - hlist_for_each_entry_safe(dreq, lp, tmp, &cache_defer_hash[hash], hash) + hlist_for_each_entry_safe(dreq, tmp, &cache_defer_hash[hash], hash) if (dreq->item == item) { __unhash_deferred_req(dreq); list_add(&dreq->recent, &pending); @@ -748,12 +740,24 @@ struct cache_reader { int offset; /* if non-0, we have a refcnt on next request */ }; +static int cache_request(struct cache_detail *detail, + struct cache_request *crq) +{ + char *bp = crq->buf; + int len = PAGE_SIZE; + + detail->cache_request(detail, crq->item, &bp, &len); + if (len < 0) + return -EAGAIN; + return PAGE_SIZE - len; +} + static ssize_t cache_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos, struct cache_detail *cd) { struct cache_reader *rp = filp->private_data; struct cache_request *rq; - struct inode *inode = filp->f_path.dentry->d_inode; + struct inode *inode = file_inode(filp); int err; if (count == 0) @@ -773,15 +777,22 @@ static ssize_t cache_read(struct file *filp, char __user *buf, size_t count, if (rp->q.list.next == &cd->queue) { spin_unlock(&queue_lock); mutex_unlock(&inode->i_mutex); - BUG_ON(rp->offset); + WARN_ON_ONCE(rp->offset); return 0; } rq = container_of(rp->q.list.next, struct cache_request, q.list); - BUG_ON(rq->q.reader); + WARN_ON_ONCE(rq->q.reader); if (rp->offset == 0) rq->readers++; spin_unlock(&queue_lock); + if (rq->len == 0) { + err = cache_request(cd, rq); + if (err < 0) + goto out; + rq->len = err; + } + if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) { err = -EAGAIN; spin_lock(&queue_lock); @@ -828,6 +839,8 @@ static ssize_t cache_do_downcall(char *kaddr, const char __user *buf, { ssize_t ret; + if (count == 0) + return -EINVAL; if (copy_from_user(kaddr, buf, count)) return -EFAULT; kaddr[count] = '\0'; @@ -882,7 +895,7 @@ static ssize_t cache_write(struct file *filp, const char __user *buf, struct cache_detail *cd) { struct address_space *mapping = filp->f_mapping; - struct inode *inode = filp->f_path.dentry->d_inode; + struct inode *inode = file_inode(filp); ssize_t ret = -EINVAL; if (!cd->cache_parse) @@ -963,8 +976,10 @@ static int cache_open(struct inode *inode, struct file *filp, nonseekable_open(inode, filp); if (filp->f_mode & FMODE_READ) { rp = kmalloc(sizeof(*rp), GFP_KERNEL); - if (!rp) + if (!rp) { + module_put(cd->owner); return -ENOMEM; + } rp->offset = 0; rp->q.reader = 1; atomic_inc(&cd->readers); @@ -1011,23 +1026,32 @@ static int cache_release(struct inode *inode, struct file *filp, 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); + } } /* @@ -1087,9 +1111,7 @@ void qword_addhex(char **bpp, int *lp, char *buf, int blen) *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--; } @@ -1136,22 +1158,23 @@ static bool cache_listeners_exist(struct cache_detail *detail) * * Each request is at most one page long. */ -int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h, - void (*cache_request)(struct cache_detail *, - struct cache_head *, - char **, - int *)) +int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h) { char *buf; struct cache_request *crq; - char *bp; - int len; + int ret = 0; + + if (!detail->cache_request) + return -EINVAL; if (!cache_listeners_exist(detail)) { 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) @@ -1163,25 +1186,24 @@ int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h, return -EAGAIN; } - bp = buf; len = PAGE_SIZE; - - cache_request(detail, h, &bp, &len); - - if (len < 0) { - kfree(buf); - kfree(crq); - return -EAGAIN; - } crq->q.reader = 0; crq->item = cache_get(h); crq->buf = buf; - crq->len = PAGE_SIZE - len; + 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); @@ -1197,7 +1219,6 @@ EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall); * key and content are both parsed by cache */ -#define isodigit(c) (isdigit(c) && c <= '7') int qword_get(char **bpp, char *dest, int bufsize) { /* return bytes copied, or -1 on error */ @@ -1269,7 +1290,7 @@ static void *c_start(struct seq_file *m, loff_t *pos) __acquires(cd->hash_lock) { loff_t n = *pos; - unsigned hash, entry; + unsigned int hash, entry; struct cache_head *ch; struct cache_detail *cd = ((struct handle*)m->private)->cd; @@ -1345,8 +1366,11 @@ static int c_show(struct seq_file *m, void *p) if (cache_check(cd, cp, NULL)) /* cache_check does a cache_put on failure */ seq_printf(m, "# "); - else + else { + if (cache_is_expired(cd, cp)) + seq_printf(m, "# "); cache_put(cp, cd); + } return cd->cache_show(m, cd, cp); } @@ -1402,11 +1426,11 @@ static ssize_t read_flush(struct file *file, char __user *buf, size_t count, loff_t *ppos, struct cache_detail *cd) { - char tbuf[20]; + char tbuf[22]; unsigned long p = *ppos; size_t len; - sprintf(tbuf, "%lu\n", convert_to_wallclock(cd->flush_time)); + snprintf(tbuf, sizeof(tbuf), "%lu\n", convert_to_wallclock(cd->flush_time)); len = strlen(tbuf); if (p >= len) return 0; @@ -1447,7 +1471,7 @@ static ssize_t write_flush(struct file *file, const char __user *buf, static ssize_t cache_read_procfs(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; + struct cache_detail *cd = PDE_DATA(file_inode(filp)); return cache_read(filp, buf, count, ppos, cd); } @@ -1455,14 +1479,14 @@ static ssize_t cache_read_procfs(struct file *filp, char __user *buf, static ssize_t cache_write_procfs(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; + struct cache_detail *cd = PDE_DATA(file_inode(filp)); return cache_write(filp, buf, count, ppos, cd); } static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait) { - struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; + struct cache_detail *cd = PDE_DATA(file_inode(filp)); return cache_poll(filp, wait, cd); } @@ -1470,22 +1494,22 @@ static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait) static long cache_ioctl_procfs(struct file *filp, unsigned int cmd, unsigned long arg) { - struct inode *inode = filp->f_path.dentry->d_inode; - struct cache_detail *cd = PDE(inode)->data; + struct inode *inode = file_inode(filp); + struct cache_detail *cd = PDE_DATA(inode); return cache_ioctl(inode, filp, cmd, arg, cd); } static int cache_open_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return cache_open(inode, filp, cd); } static int cache_release_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return cache_release(inode, filp, cd); } @@ -1503,14 +1527,14 @@ static const struct file_operations cache_file_operations_procfs = { static int content_open_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return content_open(inode, filp, cd); } static int content_release_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return content_release(inode, filp, cd); } @@ -1524,14 +1548,14 @@ static const struct file_operations content_file_operations_procfs = { static int open_flush_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return open_flush(inode, filp, cd); } static int release_flush_procfs(struct inode *inode, struct file *filp) { - struct cache_detail *cd = PDE(inode)->data; + struct cache_detail *cd = PDE_DATA(inode); return release_flush(inode, filp, cd); } @@ -1539,7 +1563,7 @@ static int release_flush_procfs(struct inode *inode, struct file *filp) static ssize_t read_flush_procfs(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; + struct cache_detail *cd = PDE_DATA(file_inode(filp)); return read_flush(filp, buf, count, ppos, cd); } @@ -1548,7 +1572,7 @@ static ssize_t write_flush_procfs(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; + struct cache_detail *cd = PDE_DATA(file_inode(filp)); return write_flush(filp, buf, count, ppos, cd); } @@ -1598,7 +1622,7 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net) if (p == NULL) goto out_nomem; - if (cd->cache_upcall || cd->cache_parse) { + if (cd->cache_request || cd->cache_parse) { p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR, cd->u.procfs.proc_ent, &cache_file_operations_procfs, cd); @@ -1607,7 +1631,7 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net) goto out_nomem; } if (cd->cache_show) { - p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR, + p = proc_create_data("content", S_IFREG|S_IRUSR, cd->u.procfs.proc_ent, &content_file_operations_procfs, cd); cd->u.procfs.content_ent = p; @@ -1628,7 +1652,7 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net) void __init cache_initialize(void) { - INIT_DELAYED_WORK_DEFERRABLE(&cache_cleaner, do_cache_clean); + INIT_DEFERRABLE_WORK(&cache_cleaner, do_cache_clean); } int cache_register_net(struct cache_detail *cd, struct net *net) @@ -1641,29 +1665,45 @@ int cache_register_net(struct cache_detail *cd, struct net *net) sunrpc_destroy_cache_detail(cd); return ret; } - -int cache_register(struct cache_detail *cd) -{ - return cache_register_net(cd, &init_net); -} -EXPORT_SYMBOL_GPL(cache_register); +EXPORT_SYMBOL_GPL(cache_register_net); void cache_unregister_net(struct cache_detail *cd, struct net *net) { remove_cache_proc_entries(cd, net); sunrpc_destroy_cache_detail(cd); } +EXPORT_SYMBOL_GPL(cache_unregister_net); -void cache_unregister(struct cache_detail *cd) +struct cache_detail *cache_create_net(struct cache_detail *tmpl, struct net *net) { - cache_unregister_net(cd, &init_net); + struct cache_detail *cd; + + 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 *), + GFP_KERNEL); + if (cd->hash_table == NULL) { + kfree(cd); + return ERR_PTR(-ENOMEM); + } + cd->net = net; + return cd; +} +EXPORT_SYMBOL_GPL(cache_create_net); + +void cache_destroy_net(struct cache_detail *cd, struct net *net) +{ + kfree(cd->hash_table); + kfree(cd); } -EXPORT_SYMBOL_GPL(cache_unregister); +EXPORT_SYMBOL_GPL(cache_destroy_net); static ssize_t cache_read_pipefs(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; + struct cache_detail *cd = RPC_I(file_inode(filp))->private; return cache_read(filp, buf, count, ppos, cd); } @@ -1671,14 +1711,14 @@ static ssize_t cache_read_pipefs(struct file *filp, char __user *buf, static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; + struct cache_detail *cd = RPC_I(file_inode(filp))->private; return cache_write(filp, buf, count, ppos, cd); } static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait) { - struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; + struct cache_detail *cd = RPC_I(file_inode(filp))->private; return cache_poll(filp, wait, cd); } @@ -1686,7 +1726,7 @@ static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait) static long cache_ioctl_pipefs(struct file *filp, unsigned int cmd, unsigned long arg) { - struct inode *inode = filp->f_dentry->d_inode; + struct inode *inode = file_inode(filp); struct cache_detail *cd = RPC_I(inode)->private; return cache_ioctl(inode, filp, cmd, arg, cd); @@ -1755,7 +1795,7 @@ static int release_flush_pipefs(struct inode *inode, struct file *filp) static ssize_t read_flush_pipefs(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; + struct cache_detail *cd = RPC_I(file_inode(filp))->private; return read_flush(filp, buf, count, ppos, cd); } @@ -1764,7 +1804,7 @@ static ssize_t write_flush_pipefs(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { - struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; + struct cache_detail *cd = RPC_I(file_inode(filp))->private; return write_flush(filp, buf, count, ppos, cd); } @@ -1778,25 +1818,14 @@ const struct file_operations cache_flush_operations_pipefs = { }; int sunrpc_cache_register_pipefs(struct dentry *parent, - const char *name, mode_t umode, + const char *name, umode_t umode, struct cache_detail *cd) { - struct qstr q; - struct dentry *dir; - int ret = 0; - - sunrpc_init_cache_detail(cd); - 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 { - sunrpc_destroy_cache_detail(cd); - 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); @@ -1804,7 +1833,6 @@ void sunrpc_cache_unregister_pipefs(struct cache_detail *cd) { rpc_remove_cache_dir(cd->u.pipefs.dir); cd->u.pipefs.dir = NULL; - sunrpc_destroy_cache_detail(cd); } EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs); |
