| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Thu, 11 Jun 2015 13:51:45 -0500
From: Seth Jennings <sjennings@...iantweb.net>
To: Dan Streetman <ddstreet@...e.org>
Cc: Andrew Morton <akpm@...ux-foundation.org>,
Linux-MM <linux-mm@...ck.org>,
linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] zswap: dynamic pool creation
On Wed, Jun 10, 2015 at 04:54:24PM -0400, Dan Streetman wrote:
> On Thu, Jun 4, 2015 at 8:13 AM, Dan Streetman <ddstreet@...e.org> wrote:
> > On Thu, Jun 4, 2015 at 8:02 AM, Dan Streetman <ddstreet@...e.org> wrote:
> >> Add dynamic creation of pools. Move the static crypto compression
> >> per-cpu transforms into each pool. Add a pointer to zswap_entry to
> >> the pool it's in.
> >
> > Seth, as far as the design, from your previous comments I assume you
> > were thinking of maintaining separate lists of zpools and compressors?
> > I do see how that will reduce duplication of zpools and compressors,
> > but it also requires adding a new pointer to each zswap_entry, and
> > increasing the amount of code to manage each list separately. And the
> > most common case in zswap will be just a single zpool and compressor,
> > not repeatedly changing params. What do you think?
>
> Any opinion on this patch? If you want, I can break it up so there's
> a list of zpools and a list of compressors. Either the combined way
> (this patch) or separate lists works for me, as long as the params are
> changeable at runtime :-)
I'm still reviewing the code. I was going to test it too but it doesn't
compile for me:
CC mm/zswap.o
mm/zswap.c: In function ‘__zswap_pool_create_fallback’:
mm/zswap.c:605:10: warning: argument to ‘sizeof’ in ‘strncpy’ call is the same expression as the destination; did you mean to provide an explicit length? [-Wsizeof-pointer-memaccess]
sizeof(zswap_compressor));
^
mm/zswap.c:607:7: error: implicit declaration of function ‘zpool_has_pool’ [-Werror=implicit-function-declaration]
if (!zpool_has_pool(zswap_zpool_type)) {
^
mm/zswap.c:611:10: warning: argument to ‘sizeof’ in ‘strncpy’ call is the same expression as the destination; did you mean to provide an explicit length? [-Wsizeof-pointer-memaccess]
sizeof(zswap_zpool_type));
^
mm/zswap.c: At top level:
mm/zswap.c:664:1: error: expected identifier or ‘(’ before ‘}’ token
}
^
mm/zswap.c:99:22: warning: ‘zswap_pool’ defined but not used [-Wunused-variable]
static struct zpool *zswap_pool;
^
mm/zswap.c:531:27: warning: ‘zswap_pool_find_get’ defined but not used [-Wunused-function]
static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
^
Seth
>
>
> >
> >>
> >> This is required by a separate patch which enables changing the
> >> zswap zpool and compressor params at runtime.
> >>
> >> Signed-off-by: Dan Streetman <ddstreet@...e.org>
> >> ---
> >> mm/zswap.c | 550 +++++++++++++++++++++++++++++++++++++++++++++----------------
> >> 1 file changed, 408 insertions(+), 142 deletions(-)
> >>
> >> diff --git a/mm/zswap.c b/mm/zswap.c
> >> index 2d5727b..fc93770 100644
> >> --- a/mm/zswap.c
> >> +++ b/mm/zswap.c
> >> @@ -99,66 +99,19 @@ module_param_named(zpool, zswap_zpool_type, charp, 0444);
> >> static struct zpool *zswap_pool;
> >>
> >> /*********************************
> >> -* compression functions
> >> +* data structures
> >> **********************************/
> >> -/* per-cpu compression transforms */
> >> -static struct crypto_comp * __percpu *zswap_comp_pcpu_tfms;
> >>
> >> -enum comp_op {
> >> - ZSWAP_COMPOP_COMPRESS,
> >> - ZSWAP_COMPOP_DECOMPRESS
> >> +struct zswap_pool {
> >> + struct zpool *zpool;
> >> + struct kref kref;
> >> + struct list_head list;
> >> + struct rcu_head rcu_head;
> >> + struct notifier_block notifier;
> >> + char tfm_name[CRYPTO_MAX_ALG_NAME];
> >> + struct crypto_comp * __percpu *tfm;
> >> };
> >>
> >> -static int zswap_comp_op(enum comp_op op, const u8 *src, unsigned int slen,
> >> - u8 *dst, unsigned int *dlen)
> >> -{
> >> - struct crypto_comp *tfm;
> >> - int ret;
> >> -
> >> - tfm = *per_cpu_ptr(zswap_comp_pcpu_tfms, get_cpu());
> >> - switch (op) {
> >> - case ZSWAP_COMPOP_COMPRESS:
> >> - ret = crypto_comp_compress(tfm, src, slen, dst, dlen);
> >> - break;
> >> - case ZSWAP_COMPOP_DECOMPRESS:
> >> - ret = crypto_comp_decompress(tfm, src, slen, dst, dlen);
> >> - break;
> >> - default:
> >> - ret = -EINVAL;
> >> - }
> >> -
> >> - put_cpu();
> >> - return ret;
> >> -}
> >> -
> >> -static int __init zswap_comp_init(void)
> >> -{
> >> - if (!crypto_has_comp(zswap_compressor, 0, 0)) {
> >> - pr_info("%s compressor not available\n", zswap_compressor);
> >> - /* fall back to default compressor */
> >> - zswap_compressor = ZSWAP_COMPRESSOR_DEFAULT;
> >> - if (!crypto_has_comp(zswap_compressor, 0, 0))
> >> - /* can't even load the default compressor */
> >> - return -ENODEV;
> >> - }
> >> - pr_info("using %s compressor\n", zswap_compressor);
> >> -
> >> - /* alloc percpu transforms */
> >> - zswap_comp_pcpu_tfms = alloc_percpu(struct crypto_comp *);
> >> - if (!zswap_comp_pcpu_tfms)
> >> - return -ENOMEM;
> >> - return 0;
> >> -}
> >> -
> >> -static void __init zswap_comp_exit(void)
> >> -{
> >> - /* free percpu transforms */
> >> - free_percpu(zswap_comp_pcpu_tfms);
> >> -}
> >> -
> >> -/*********************************
> >> -* data structures
> >> -**********************************/
> >> /*
> >> * struct zswap_entry
> >> *
> >> @@ -166,22 +119,24 @@ static void __init zswap_comp_exit(void)
> >> * page within zswap.
> >> *
> >> * rbnode - links the entry into red-black tree for the appropriate swap type
> >> + * offset - the swap offset for the entry. Index into the red-black tree.
> >> * refcount - the number of outstanding reference to the entry. This is needed
> >> * to protect against premature freeing of the entry by code
> >> * concurrent calls to load, invalidate, and writeback. The lock
> >> * for the zswap_tree structure that contains the entry must
> >> * be held while changing the refcount. Since the lock must
> >> * be held, there is no reason to also make refcount atomic.
> >> - * offset - the swap offset for the entry. Index into the red-black tree.
> >> - * handle - zpool allocation handle that stores the compressed page data
> >> * length - the length in bytes of the compressed page data. Needed during
> >> * decompression
> >> + * pool - the zswap_pool the entry's data is in
> >> + * handle - zpool allocation handle that stores the compressed page data
> >> */
> >> struct zswap_entry {
> >> struct rb_node rbnode;
> >> pgoff_t offset;
> >> int refcount;
> >> unsigned int length;
> >> + struct zswap_pool *pool;
> >> unsigned long handle;
> >> };
> >>
> >> @@ -201,6 +156,44 @@ struct zswap_tree {
> >>
> >> static struct zswap_tree *zswap_trees[MAX_SWAPFILES];
> >>
> >> +/* RCU-protected iteration */
> >> +static LIST_HEAD(zswap_pools);
> >> +/* protects zswap_pools list modification */
> >> +static DEFINE_SPINLOCK(zswap_pools_lock);
> >> +
> >> +/*********************************
> >> +* helpers and fwd declarations
> >> +**********************************/
> >> +
> >> +#define zswap_pool_debug(msg, p) \
> >> + pr_debug("%s pool %s/%s\n", msg, (p)->tfm_name, \
> >> + zpool_get_type((p)->zpool))
> >> +
> >> +static int zswap_writeback_entry(struct zpool *pool, unsigned long handle);
> >> +static int zswap_pool_get(struct zswap_pool *pool);
> >> +static void zswap_pool_put(struct zswap_pool *pool);
> >> +
> >> +static bool zswap_is_full(void)
> >> +{
> >> + return totalram_pages * zswap_max_pool_percent / 100 <
> >> + DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
> >> +}
> >> +
> >> +static void zswap_update_total_size(void)
> >> +{
> >> + struct zswap_pool *pool;
> >> + u64 total = 0;
> >> +
> >> + rcu_read_lock();
> >> +
> >> + list_for_each_entry_rcu(pool, &zswap_pools, list)
> >> + total += zpool_get_total_size(pool->zpool);
> >> +
> >> + rcu_read_unlock();
> >> +
> >> + zswap_pool_total_size = total;
> >> +}
> >> +
> >> /*********************************
> >> * zswap entry functions
> >> **********************************/
> >> @@ -294,10 +287,11 @@ static void zswap_rb_erase(struct rb_root *root, struct zswap_entry *entry)
> >> */
> >> static void zswap_free_entry(struct zswap_entry *entry)
> >> {
> >> - zpool_free(zswap_pool, entry->handle);
> >> + zpool_free(entry->pool->zpool, entry->handle);
> >> + zswap_pool_put(entry->pool);
> >> zswap_entry_cache_free(entry);
> >> atomic_dec(&zswap_stored_pages);
> >> - zswap_pool_total_size = zpool_get_total_size(zswap_pool);
> >> + zswap_update_total_size();
> >> }
> >>
> >> /* caller must hold the tree lock */
> >> @@ -339,35 +333,21 @@ static struct zswap_entry *zswap_entry_find_get(struct rb_root *root,
> >> **********************************/
> >> static DEFINE_PER_CPU(u8 *, zswap_dstmem);
> >>
> >> -static int __zswap_cpu_notifier(unsigned long action, unsigned long cpu)
> >> +static int __zswap_cpu_dstmem_notifier(unsigned long action, unsigned long cpu)
> >> {
> >> - struct crypto_comp *tfm;
> >> u8 *dst;
> >>
> >> switch (action) {
> >> case CPU_UP_PREPARE:
> >> - tfm = crypto_alloc_comp(zswap_compressor, 0, 0);
> >> - if (IS_ERR(tfm)) {
> >> - pr_err("can't allocate compressor transform\n");
> >> - return NOTIFY_BAD;
> >> - }
> >> - *per_cpu_ptr(zswap_comp_pcpu_tfms, cpu) = tfm;
> >> dst = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
> >> if (!dst) {
> >> pr_err("can't allocate compressor buffer\n");
> >> - crypto_free_comp(tfm);
> >> - *per_cpu_ptr(zswap_comp_pcpu_tfms, cpu) = NULL;
> >> return NOTIFY_BAD;
> >> }
> >> per_cpu(zswap_dstmem, cpu) = dst;
> >> break;
> >> case CPU_DEAD:
> >> case CPU_UP_CANCELED:
> >> - tfm = *per_cpu_ptr(zswap_comp_pcpu_tfms, cpu);
> >> - if (tfm) {
> >> - crypto_free_comp(tfm);
> >> - *per_cpu_ptr(zswap_comp_pcpu_tfms, cpu) = NULL;
> >> - }
> >> dst = per_cpu(zswap_dstmem, cpu);
> >> kfree(dst);
> >> per_cpu(zswap_dstmem, cpu) = NULL;
> >> @@ -378,43 +358,309 @@ static int __zswap_cpu_notifier(unsigned long action, unsigned long cpu)
> >> return NOTIFY_OK;
> >> }
> >>
> >> -static int zswap_cpu_notifier(struct notifier_block *nb,
> >> - unsigned long action, void *pcpu)
> >> +static int zswap_cpu_dstmem_notifier(struct notifier_block *nb,
> >> + unsigned long action, void *pcpu)
> >> {
> >> - unsigned long cpu = (unsigned long)pcpu;
> >> - return __zswap_cpu_notifier(action, cpu);
> >> + return __zswap_cpu_dstmem_notifier(action, (unsigned long)pcpu);
> >> }
> >>
> >> -static struct notifier_block zswap_cpu_notifier_block = {
> >> - .notifier_call = zswap_cpu_notifier
> >> +static struct notifier_block zswap_dstmem_notifier = {
> >> + .notifier_call = zswap_cpu_dstmem_notifier,
> >> };
> >>
> >> -static int __init zswap_cpu_init(void)
> >> +static int __init zswap_cpu_dstmem_init(void)
> >> {
> >> unsigned long cpu;
> >>
> >> cpu_notifier_register_begin();
> >> for_each_online_cpu(cpu)
> >> - if (__zswap_cpu_notifier(CPU_UP_PREPARE, cpu) != NOTIFY_OK)
> >> + if (__zswap_cpu_dstmem_notifier(CPU_UP_PREPARE, cpu) ==
> >> + NOTIFY_BAD)
> >> goto cleanup;
> >> - __register_cpu_notifier(&zswap_cpu_notifier_block);
> >> + __register_cpu_notifier(&zswap_dstmem_notifier);
> >> cpu_notifier_register_done();
> >> return 0;
> >>
> >> cleanup:
> >> for_each_online_cpu(cpu)
> >> - __zswap_cpu_notifier(CPU_UP_CANCELED, cpu);
> >> + __zswap_cpu_dstmem_notifier(CPU_UP_CANCELED, cpu);
> >> cpu_notifier_register_done();
> >> return -ENOMEM;
> >> }
> >>
> >> +static void zswap_cpu_dstmem_destroy(void)
> >> +{
> >> + unsigned long cpu;
> >> +
> >> + cpu_notifier_register_begin();
> >> + for_each_online_cpu(cpu)
> >> + __zswap_cpu_dstmem_notifier(CPU_UP_CANCELED, cpu);
> >> + __unregister_cpu_notifier(&zswap_dstmem_notifier);
> >> + cpu_notifier_register_done();
> >> +}
> >> +
> >> +static int __zswap_cpu_comp_notifier(struct zswap_pool *pool,
> >> + unsigned long action, unsigned long cpu)
> >> +{
> >> + struct crypto_comp *tfm;
> >> +
> >> + switch (action) {
> >> + case CPU_UP_PREPARE:
> >> + if (WARN_ON(*per_cpu_ptr(pool->tfm, cpu)))
> >> + break;
> >> + tfm = crypto_alloc_comp(pool->tfm_name, 0, 0);
> >> + if (IS_ERR_OR_NULL(tfm)) {
> >> + pr_err("could not alloc crypto comp %s : %ld\n",
> >> + pool->tfm_name, PTR_ERR(tfm));
> >> + return NOTIFY_BAD;
> >> + }
> >> + *per_cpu_ptr(pool->tfm, cpu) = tfm;
> >> + break;
> >> + case CPU_DEAD:
> >> + case CPU_UP_CANCELED:
> >> + tfm = *per_cpu_ptr(pool->tfm, cpu);
> >> + if (!IS_ERR_OR_NULL(tfm))
> >> + crypto_free_comp(tfm);
> >> + *per_cpu_ptr(pool->tfm, cpu) = NULL;
> >> + break;
> >> + default:
> >> + break;
> >> + }
> >> + return NOTIFY_OK;
> >> +}
> >> +
> >> +static int zswap_cpu_comp_notifier(struct notifier_block *nb,
> >> + unsigned long action, void *pcpu)
> >> +{
> >> + unsigned long cpu = (unsigned long)pcpu;
> >> + struct zswap_pool *pool = container_of(nb, typeof(*pool), notifier);
> >> +
> >> + return __zswap_cpu_comp_notifier(pool, action, cpu);
> >> +}
> >> +
> >> +static int zswap_cpu_comp_init(struct zswap_pool *pool)
> >> +{
> >> + unsigned long cpu;
> >> +
> >> + memset(&pool->notifier, 0, sizeof(pool->notifier));
> >> + pool->notifier.notifier_call = zswap_cpu_comp_notifier;
> >> +
> >> + cpu_notifier_register_begin();
> >> + for_each_online_cpu(cpu)
> >> + if (__zswap_cpu_comp_notifier(pool, CPU_UP_PREPARE, cpu) ==
> >> + NOTIFY_BAD)
> >> + goto cleanup;
> >> + __register_cpu_notifier(&pool->notifier);
> >> + cpu_notifier_register_done();
> >> + return 0;
> >> +
> >> +cleanup:
> >> + for_each_online_cpu(cpu)
> >> + __zswap_cpu_comp_notifier(pool, CPU_UP_CANCELED, cpu);
> >> + cpu_notifier_register_done();
> >> + return -ENOMEM;
> >> +}
> >> +
> >> +static void zswap_cpu_comp_destroy(struct zswap_pool *pool)
> >> +{
> >> + unsigned long cpu;
> >> +
> >> + cpu_notifier_register_begin();
> >> + for_each_online_cpu(cpu)
> >> + __zswap_cpu_comp_notifier(pool, CPU_UP_CANCELED, cpu);
> >> + __unregister_cpu_notifier(&pool->notifier);
> >> + cpu_notifier_register_done();
> >> +}
> >> +
> >> /*********************************
> >> -* helpers
> >> +* pool functions
> >> **********************************/
> >> -static bool zswap_is_full(void)
> >> +
> >> +static struct zswap_pool *__zswap_pool_current(void)
> >> {
> >> - return totalram_pages * zswap_max_pool_percent / 100 <
> >> - DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
> >> + struct zswap_pool *pool;
> >> +
> >> + pool = list_first_or_null_rcu(&zswap_pools, typeof(*pool), list);
> >> + WARN_ON(!pool);
> >> +
> >> + return pool;
> >> +}
> >> +
> >> +static struct zswap_pool *zswap_pool_current(void)
> >> +{
> >> + assert_spin_locked(&zswap_pools_lock);
> >> +
> >> + return __zswap_pool_current();
> >> +}
> >> +
> >> +static struct zswap_pool *zswap_pool_current_get(void)
> >> +{
> >> + struct zswap_pool *pool;
> >> +
> >> + rcu_read_lock();
> >> +
> >> + pool = __zswap_pool_current();
> >> + if (!pool || !zswap_pool_get(pool))
> >> + pool = NULL;
> >> +
> >> + rcu_read_unlock();
> >> +
> >> + return pool;
> >> +}
> >> +
> >> +static struct zswap_pool *zswap_pool_last_get(void)
> >> +{
> >> + struct zswap_pool *pool, *last = NULL;
> >> +
> >> + rcu_read_lock();
> >> +
> >> + list_for_each_entry_rcu(pool, &zswap_pools, list)
> >> + last = pool;
> >> + if (!WARN_ON(!last) && !zswap_pool_get(last))
> >> + last = NULL;
> >> +
> >> + rcu_read_unlock();
> >> +
> >> + return last;
> >> +}
> >> +
> >> +static struct zpool_ops zswap_zpool_ops = {
> >> + .evict = zswap_writeback_entry
> >> +};
> >> +
> >> +static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
> >> +{
> >> + struct zswap_pool *pool;
> >> +
> >> + assert_spin_locked(&zswap_pools_lock);
> >> +
> >> + list_for_each_entry_rcu(pool, &zswap_pools, list) {
> >> + if (strncmp(pool->tfm_name, compressor, sizeof(pool->tfm_name)))
> >> + continue;
> >> + if (strncmp(zpool_get_type(pool->zpool), type,
> >> + sizeof(zswap_zpool_type)))
> >> + continue;
> >> + /* if we can't get it, it's about to be destroyed */
> >> + if (!zswap_pool_get(pool))
> >> + continue;
> >> + return pool;
> >> + }
> >> +
> >> + return NULL;
> >> +}
> >> +
> >> +static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
> >> +{
> >> + struct zswap_pool *pool;
> >> + gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN;
> >> +
> >> + pool = kzalloc(sizeof(*pool), GFP_KERNEL);
> >> + if (!pool) {
> >> + pr_err("pool alloc failed\n");
> >> + return NULL;
> >> + }
> >> +
> >> + pool->zpool = zpool_create_pool(type, "zswap", gfp, &zswap_zpool_ops);
> >> + if (!pool->zpool) {
> >> + pr_err("%s zpool not available\n", type);
> >> + goto error;
> >> + }
> >> + pr_debug("using %s zpool\n", zpool_get_type(pool->zpool));
> >> +
> >> + strlcpy(pool->tfm_name, compressor, sizeof(pool->tfm_name));
> >> + pool->tfm = alloc_percpu(struct crypto_comp *);
> >> + if (!pool->tfm) {
> >> + pr_err("percpu alloc failed\n");
> >> + goto error;
> >> + }
> >> +
> >> + if (zswap_cpu_comp_init(pool))
> >> + goto error;
> >> + pr_debug("using %s compressor\n", pool->tfm_name);
> >> +
> >> + /* being the current pool takes 1 ref; this func expects the
> >> + * caller to always add the new pool as the current pool
> >> + */
> >> + kref_init(&pool->kref);
> >> + INIT_LIST_HEAD(&pool->list);
> >> +
> >> + zswap_pool_debug("created", pool);
> >> +
> >> + return pool;
> >> +
> >> +error:
> >> + free_percpu(pool->tfm);
> >> + if (pool->zpool)
> >> + zpool_destroy_pool(pool->zpool);
> >> + kfree(pool);
> >> + return NULL;
> >> +}
> >> +
> >> +static struct zswap_pool *__zswap_pool_create_fallback(void)
> >> +{
> >> + if (!crypto_has_comp(zswap_compressor, 0, 0)) {
> >> + pr_err("compressor %s not available, using default %s\n",
> >> + zswap_compressor, ZSWAP_COMPRESSOR_DEFAULT);
> >> + strncpy(zswap_compressor, ZSWAP_COMPRESSOR_DEFAULT,
> >> + sizeof(zswap_compressor));
> >> + }
> >> + if (!zpool_has_pool(zswap_zpool_type)) {
> >> + pr_err("zpool %s not available, using default %s\n",
> >> + zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT);
> >> + strncpy(zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT,
> >> + sizeof(zswap_zpool_type));
> >> + }
> >> +
> >> + return zswap_pool_create(zswap_zpool_type, zswap_compressor);
> >> +}
> >> +
> >> +static void zswap_pool_destroy(struct zswap_pool *pool)
> >> +{
> >> + zswap_pool_debug("destroying", pool);
> >> +
> >> + zswap_cpu_comp_destroy(pool);
> >> + free_percpu(pool->tfm);
> >> + zpool_destroy_pool(pool->zpool);
> >> + kfree(pool);
> >> +}
> >> +
> >> +static int __must_check zswap_pool_get(struct zswap_pool *pool)
> >> +{
> >> + return kref_get_unless_zero(&pool->kref);
> >> +}
> >> +
> >> +static void __zswap_pool_release(struct rcu_head *head)
> >> +{
> >> + struct zswap_pool *pool = container_of(head, typeof(*pool), rcu_head);
> >> +
> >> + /* nobody should have been able to get a kref... */
> >> + WARN_ON(kref_get_unless_zero(&pool->kref));
> >> +
> >> + /* pool is now off zswap_pools list and has no references. */
> >> + zswap_pool_destroy(pool);
> >> +}
> >> +
> >> +static void __zswap_pool_empty(struct kref *kref)
> >> +{
> >> + struct zswap_pool *pool;
> >> +
> >> + pool = container_of(kref, typeof(*pool), kref);
> >> +
> >> + spin_lock(&zswap_pools_lock);
> >> +
> >> + WARN_ON(pool == zswap_pool_current());
> >> +
> >> + list_del_rcu(&pool->list);
> >> + call_rcu(&pool->rcu_head, __zswap_pool_release);
> >> +
> >> + spin_unlock(&zswap_pools_lock);
> >> +}
> >> +
> >> +static void zswap_pool_put(struct zswap_pool *pool)
> >> +{
> >> + kref_put(&pool->kref, __zswap_pool_empty);
> >> +}
> >> +
> >> }
> >>
> >> /*********************************
> >> @@ -538,6 +784,7 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle)
> >> pgoff_t offset;
> >> struct zswap_entry *entry;
> >> struct page *page;
> >> + struct crypto_comp *tfm;
> >> u8 *src, *dst;
> >> unsigned int dlen;
> >> int ret;
> >> @@ -578,13 +825,15 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle)
> >> case ZSWAP_SWAPCACHE_NEW: /* page is locked */
> >> /* decompress */
> >> dlen = PAGE_SIZE;
> >> - src = (u8 *)zpool_map_handle(zswap_pool, entry->handle,
> >> + src = (u8 *)zpool_map_handle(entry->pool->zpool, entry->handle,
> >> ZPOOL_MM_RO) + sizeof(struct zswap_header);
> >> dst = kmap_atomic(page);
> >> - ret = zswap_comp_op(ZSWAP_COMPOP_DECOMPRESS, src,
> >> - entry->length, dst, &dlen);
> >> + tfm = *get_cpu_ptr(entry->pool->tfm);
> >> + ret = crypto_comp_decompress(tfm, src, entry->length,
> >> + dst, &dlen);
> >> + put_cpu_ptr(entry->pool->tfm);
> >> kunmap_atomic(dst);
> >> - zpool_unmap_handle(zswap_pool, entry->handle);
> >> + zpool_unmap_handle(entry->pool->zpool, entry->handle);
> >> BUG_ON(ret);
> >> BUG_ON(dlen != PAGE_SIZE);
> >>
> >> @@ -633,6 +882,22 @@ end:
> >> return ret;
> >> }
> >>
> >> +static int zswap_shrink(void)
> >> +{
> >> + struct zswap_pool *pool;
> >> + int ret;
> >> +
> >> + pool = zswap_pool_last_get();
> >> + if (!pool)
> >> + return -ENOENT;
> >> +
> >> + ret = zpool_shrink(pool->zpool, 1, NULL);
> >> +
> >> + zswap_pool_put(pool);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> /*********************************
> >> * frontswap hooks
> >> **********************************/
> >> @@ -642,6 +907,7 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
> >> {
> >> struct zswap_tree *tree = zswap_trees[type];
> >> struct zswap_entry *entry, *dupentry;
> >> + struct crypto_comp *tfm;
> >> int ret;
> >> unsigned int dlen = PAGE_SIZE, len;
> >> unsigned long handle;
> >> @@ -657,7 +923,7 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
> >> /* reclaim space if needed */
> >> if (zswap_is_full()) {
> >> zswap_pool_limit_hit++;
> >> - if (zpool_shrink(zswap_pool, 1, NULL)) {
> >> + if (zswap_shrink()) {
> >> zswap_reject_reclaim_fail++;
> >> ret = -ENOMEM;
> >> goto reject;
> >> @@ -672,33 +938,42 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
> >> goto reject;
> >> }
> >>
> >> + /* if entry is successfully added, it keeps the reference */
> >> + entry->pool = zswap_pool_current_get();
> >> + if (!entry->pool) {
> >> + ret = -EINVAL;
> >> + goto freepage;
> >> + }
> >> +
> >> /* compress */
> >> dst = get_cpu_var(zswap_dstmem);
> >> + tfm = *get_cpu_ptr(entry->pool->tfm);
> >> src = kmap_atomic(page);
> >> - ret = zswap_comp_op(ZSWAP_COMPOP_COMPRESS, src, PAGE_SIZE, dst, &dlen);
> >> + ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen);
> >> kunmap_atomic(src);
> >> + put_cpu_ptr(entry->pool->tfm);
> >> if (ret) {
> >> ret = -EINVAL;
> >> - goto freepage;
> >> + goto put_dstmem;
> >> }
> >>
> >> /* store */
> >> len = dlen + sizeof(struct zswap_header);
> >> - ret = zpool_malloc(zswap_pool, len, __GFP_NORETRY | __GFP_NOWARN,
> >> - &handle);
> >> + ret = zpool_malloc(entry->pool->zpool, len,
> >> + __GFP_NORETRY | __GFP_NOWARN, &handle);
> >> if (ret == -ENOSPC) {
> >> zswap_reject_compress_poor++;
> >> - goto freepage;
> >> + goto put_dstmem;
> >> }
> >> if (ret) {
> >> zswap_reject_alloc_fail++;
> >> - goto freepage;
> >> + goto put_dstmem;
> >> }
> >> - zhdr = zpool_map_handle(zswap_pool, handle, ZPOOL_MM_RW);
> >> + zhdr = zpool_map_handle(entry->pool->zpool, handle, ZPOOL_MM_RW);
> >> zhdr->swpentry = swp_entry(type, offset);
> >> buf = (u8 *)(zhdr + 1);
> >> memcpy(buf, dst, dlen);
> >> - zpool_unmap_handle(zswap_pool, handle);
> >> + zpool_unmap_handle(entry->pool->zpool, handle);
> >> put_cpu_var(zswap_dstmem);
> >>
> >> /* populate entry */
> >> @@ -721,12 +996,14 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
> >>
> >> /* update stats */
> >> atomic_inc(&zswap_stored_pages);
> >> - zswap_pool_total_size = zpool_get_total_size(zswap_pool);
> >> + zswap_update_total_size();
> >>
> >> return 0;
> >>
> >> -freepage:
> >> +put_dstmem:
> >> put_cpu_var(zswap_dstmem);
> >> + zswap_pool_put(entry->pool);
> >> +freepage:
> >> zswap_entry_cache_free(entry);
> >> reject:
> >> return ret;
> >> @@ -741,6 +1018,7 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset,
> >> {
> >> struct zswap_tree *tree = zswap_trees[type];
> >> struct zswap_entry *entry;
> >> + struct crypto_comp *tfm;
> >> u8 *src, *dst;
> >> unsigned int dlen;
> >> int ret;
> >> @@ -757,13 +1035,14 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset,
> >>
> >> /* decompress */
> >> dlen = PAGE_SIZE;
> >> - src = (u8 *)zpool_map_handle(zswap_pool, entry->handle,
> >> + src = (u8 *)zpool_map_handle(entry->pool->zpool, entry->handle,
> >> ZPOOL_MM_RO) + sizeof(struct zswap_header);
> >> dst = kmap_atomic(page);
> >> - ret = zswap_comp_op(ZSWAP_COMPOP_DECOMPRESS, src, entry->length,
> >> - dst, &dlen);
> >> + tfm = *get_cpu_ptr(entry->pool->tfm);
> >> + ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen);
> >> + put_cpu_ptr(entry->pool->tfm);
> >> kunmap_atomic(dst);
> >> - zpool_unmap_handle(zswap_pool, entry->handle);
> >> + zpool_unmap_handle(entry->pool->zpool, entry->handle);
> >> BUG_ON(ret);
> >>
> >> spin_lock(&tree->lock);
> >> @@ -816,10 +1095,6 @@ static void zswap_frontswap_invalidate_area(unsigned type)
> >> zswap_trees[type] = NULL;
> >> }
> >>
> >> -static struct zpool_ops zswap_zpool_ops = {
> >> - .evict = zswap_writeback_entry
> >> -};
> >> -
> >> static void zswap_frontswap_init(unsigned type)
> >> {
> >> struct zswap_tree *tree;
> >> @@ -900,49 +1175,40 @@ static void __exit zswap_debugfs_exit(void) { }
> >> **********************************/
> >> static int __init init_zswap(void)
> >> {
> >> - gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN;
> >> + struct zswap_pool *pool;
> >>
> >> - pr_info("loading zswap\n");
> >> -
> >> - zswap_pool = zpool_create_pool(zswap_zpool_type, "zswap", gfp,
> >> - &zswap_zpool_ops);
> >> - if (!zswap_pool && strcmp(zswap_zpool_type, ZSWAP_ZPOOL_DEFAULT)) {
> >> - pr_info("%s zpool not available\n", zswap_zpool_type);
> >> - zswap_zpool_type = ZSWAP_ZPOOL_DEFAULT;
> >> - zswap_pool = zpool_create_pool(zswap_zpool_type, "zswap", gfp,
> >> - &zswap_zpool_ops);
> >> - }
> >> - if (!zswap_pool) {
> >> - pr_err("%s zpool not available\n", zswap_zpool_type);
> >> - pr_err("zpool creation failed\n");
> >> - goto error;
> >> - }
> >> - pr_info("using %s pool\n", zswap_zpool_type);
> >> + pr_info("loading\n");
> >>
> >> if (zswap_entry_cache_create()) {
> >> pr_err("entry cache creation failed\n");
> >> - goto cachefail;
> >> + goto cache_fail;
> >> }
> >> - if (zswap_comp_init()) {
> >> - pr_err("compressor initialization failed\n");
> >> - goto compfail;
> >> +
> >> + if (zswap_cpu_dstmem_init()) {
> >> + pr_err("dstmem alloc failed\n");
> >> + goto dstmem_fail;
> >> }
> >> - if (zswap_cpu_init()) {
> >> - pr_err("per-cpu initialization failed\n");
> >> - goto pcpufail;
> >> +
> >> + pool = __zswap_pool_create_fallback();
> >> + if (!pool) {
> >> + pr_err("pool creation failed\n");
> >> + goto pool_fail;
> >> }
> >> + pr_info("loaded using pool %s/%s\n", pool->tfm_name,
> >> + zpool_get_type(pool->zpool));
> >> +
> >> + list_add(&pool->list, &zswap_pools);
> >>
> >> frontswap_register_ops(&zswap_frontswap_ops);
> >> if (zswap_debugfs_init())
> >> pr_warn("debugfs initialization failed\n");
> >> return 0;
> >> -pcpufail:
> >> - zswap_comp_exit();
> >> -compfail:
> >> +
> >> +pool_fail:
> >> + zswap_cpu_dstmem_destroy();
> >> +dstmem_fail:
> >> zswap_entry_cache_destroy();
> >> -cachefail:
> >> - zpool_destroy_pool(zswap_pool);
> >> -error:
> >> +cache_fail:
> >> return -ENOMEM;
> >> }
> >> /* must be late so crypto has time to come up */
> >> --
> >> 2.1.0
> >>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists