From d46a5ac7a7e2045e33c6ad6ffb8cf18a7e86a15a Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Wed, 19 May 2010 13:43:14 +1000 Subject: padata: Use a timer to handle remaining objects in the reorder queues padata_get_next needs to check whether the next object that need serialization must be parallel processed by the local cpu. This check was wrong implemented and returned always true, so the try_again loop in padata_reorder was never taken. This can lead to object leaks in some rare cases due to a race that appears with the trylock in padata_reorder. The try_again loop was not a good idea after all, because a cpu could take that loop frequently, so we handle this with a timer instead. This patch adds a timer to handle the race that appears with the trylock. If cpu1 queues an object to the reorder queue while cpu2 holds the pd->lock but left the while loop in padata_reorder already, cpu2 can't care for this object and cpu1 exits because it can't get the lock. Usually the next cpu that takes the lock cares for this object too. We need the timer just if this object was the last one that arrives to the reorder queues. The timer function sends it out in this case. Signed-off-by: Steffen Klassert Signed-off-by: Herbert Xu --- include/linux/padata.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/padata.h b/include/linux/padata.h index 51611da9c498..64836a63bd17 100644 --- a/include/linux/padata.h +++ b/include/linux/padata.h @@ -24,6 +24,7 @@ #include #include #include +#include struct padata_priv { struct list_head list; @@ -60,6 +61,7 @@ struct parallel_data { unsigned int max_seq_nr; cpumask_var_t cpumask; spinlock_t lock; + struct timer_list timer; }; struct padata_instance { -- cgit v1.2.3 From 0198ffd135f51d4fbb0c50036395716c06632ed9 Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Wed, 19 May 2010 13:44:27 +1000 Subject: padata: Add some code comments Signed-off-by: Steffen Klassert Signed-off-by: Herbert Xu --- include/linux/padata.h | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) (limited to 'include') diff --git a/include/linux/padata.h b/include/linux/padata.h index 64836a63bd17..8d8406246eef 100644 --- a/include/linux/padata.h +++ b/include/linux/padata.h @@ -26,6 +26,17 @@ #include #include +/** + * struct padata_priv - Embedded to the users data structure. + * + * @list: List entry, to attach to the padata lists. + * @pd: Pointer to the internal control structure. + * @cb_cpu: Callback cpu for serializatioon. + * @seq_nr: Sequence number of the parallelized data object. + * @info: Used to pass information from the parallel to the serial function. + * @parallel: Parallel execution function. + * @serial: Serial complete function. + */ struct padata_priv { struct list_head list; struct parallel_data *pd; @@ -36,11 +47,29 @@ struct padata_priv { void (*serial)(struct padata_priv *padata); }; +/** + * struct padata_list + * + * @list: List head. + * @lock: List lock. + */ struct padata_list { struct list_head list; spinlock_t lock; }; +/** + * struct padata_queue - The percpu padata queues. + * + * @parallel: List to wait for parallelization. + * @reorder: List to wait for reordering after parallel processing. + * @serial: List to wait for serialization after reordering. + * @pwork: work struct for parallelization. + * @swork: work struct for serialization. + * @pd: Backpointer to the internal control structure. + * @num_obj: Number of objects that are processed by this cpu. + * @cpu_index: Index of the cpu. + */ struct padata_queue { struct padata_list parallel; struct padata_list reorder; @@ -52,6 +81,20 @@ struct padata_queue { int cpu_index; }; +/** + * struct parallel_data - Internal control structure, covers everything + * that depends on the cpumask in use. + * + * @pinst: padata instance. + * @queue: percpu padata queues. + * @seq_nr: The sequence number that will be attached to the next object. + * @reorder_objects: Number of objects waiting in the reorder queues. + * @refcnt: Number of objects holding a reference on this parallel_data. + * @max_seq_nr: Maximal used sequence number. + * @cpumask: cpumask in use. + * @lock: Reorder lock. + * @timer: Reorder timer. + */ struct parallel_data { struct padata_instance *pinst; struct padata_queue *queue; @@ -64,6 +107,16 @@ struct parallel_data { struct timer_list timer; }; +/** + * struct padata_instance - The overall control structure. + * + * @cpu_notifier: cpu hotplug notifier. + * @wq: The workqueue in use. + * @pd: The internal control structure. + * @cpumask: User supplied cpumask. + * @lock: padata instance lock. + * @flags: padata flags. + */ struct padata_instance { struct notifier_block cpu_notifier; struct workqueue_struct *wq; -- cgit v1.2.3 From bf06099db18a1244957076e51847c644cfe46808 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 19 May 2010 14:13:07 +1000 Subject: crypto: skcipher - Add ablkcipher_walk interfaces These are akin to the blkcipher_walk helpers. The main differences in the async variant are: 1) Only physical walking is supported. We can't hold on to kmap mappings across the async operation to support virtual ablkcipher_walk operations anyways. 2) Bounce buffers used for async more need to be persistent and freed at a later point in time when the async op completes. Therefore we maintain a list of writeback buffers and require that the ablkcipher_walk user call the 'complete' operation so we can copy the bounce buffers out to the real buffers and free up the bounce buffer chunks. These interfaces will be used by the new Niagara2 crypto driver. Signed-off-by: David S. Miller Signed-off-by: Herbert Xu --- include/crypto/algapi.h | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) (limited to 'include') diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h index fc0d575c71e0..59c3e5bd2c06 100644 --- a/include/crypto/algapi.h +++ b/include/crypto/algapi.h @@ -103,6 +103,23 @@ struct blkcipher_walk { unsigned int blocksize; }; +struct ablkcipher_walk { + struct { + struct page *page; + unsigned int offset; + } src, dst; + + struct scatter_walk in; + unsigned int nbytes; + struct scatter_walk out; + unsigned int total; + struct list_head buffers; + u8 *iv_buffer; + u8 *iv; + int flags; + unsigned int blocksize; +}; + extern const struct crypto_type crypto_ablkcipher_type; extern const struct crypto_type crypto_aead_type; extern const struct crypto_type crypto_blkcipher_type; @@ -173,6 +190,12 @@ int blkcipher_walk_virt_block(struct blkcipher_desc *desc, struct blkcipher_walk *walk, unsigned int blocksize); +int ablkcipher_walk_done(struct ablkcipher_request *req, + struct ablkcipher_walk *walk, int err); +int ablkcipher_walk_phys(struct ablkcipher_request *req, + struct ablkcipher_walk *walk); +void __ablkcipher_walk_complete(struct ablkcipher_walk *walk); + static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm) { return PTR_ALIGN(crypto_tfm_ctx(tfm), @@ -283,6 +306,23 @@ static inline void blkcipher_walk_init(struct blkcipher_walk *walk, walk->total = nbytes; } +static inline void ablkcipher_walk_init(struct ablkcipher_walk *walk, + struct scatterlist *dst, + struct scatterlist *src, + unsigned int nbytes) +{ + walk->in.sg = src; + walk->out.sg = dst; + walk->total = nbytes; + INIT_LIST_HEAD(&walk->buffers); +} + +static inline void ablkcipher_walk_complete(struct ablkcipher_walk *walk) +{ + if (unlikely(!list_empty(&walk->buffers))) + __ablkcipher_walk_complete(walk); +} + static inline struct crypto_async_request *crypto_get_backlog( struct crypto_queue *queue) { -- cgit v1.2.3