diff options
| -rw-r--r-- | mm/dmapool.c | 407 |
1 files changed, 202 insertions, 205 deletions
diff --git a/mm/dmapool.c b/mm/dmapool.c index a7eb5d0eb2da..d2b0f8fc9649 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -15,7 +15,7 @@ * represented by the 'struct dma_pool' which keeps a doubly-linked list of * allocated pages. Each page in the page_list is split into blocks of at * least 'size' bytes. Free blocks are tracked in an unsorted singly-linked - * list of free blocks within the page. Used blocks aren't tracked, but we + * list of free blocks across all pages. Used blocks aren't tracked, but we * keep a count of how many are currently allocated from each page. */ @@ -40,13 +40,22 @@ #define DMAPOOL_DEBUG 1 #endif +struct dma_block { + struct dma_block *next_block; + dma_addr_t dma; +}; + struct dma_pool { /* the pool */ struct list_head page_list; spinlock_t lock; - size_t size; + struct dma_block *next_block; + size_t nr_blocks; + size_t nr_active; + size_t nr_pages; struct device *dev; - size_t allocation; - size_t boundary; + unsigned int size; + unsigned int allocation; + unsigned int boundary; char name[32]; struct list_head pools; }; @@ -55,8 +64,6 @@ struct dma_page { /* cacheable header for 'allocation' bytes */ struct list_head page_list; void *vaddr; dma_addr_t dma; - unsigned int in_use; - unsigned int offset; }; static DEFINE_MUTEX(pools_lock); @@ -64,46 +71,133 @@ static DEFINE_MUTEX(pools_reg_lock); static ssize_t pools_show(struct device *dev, struct device_attribute *attr, char *buf) { - unsigned temp; - unsigned size; - char *next; - struct dma_page *page; struct dma_pool *pool; + unsigned size; - next = buf; - size = PAGE_SIZE; - - temp = scnprintf(next, size, "poolinfo - 0.1\n"); - size -= temp; - next += temp; + size = sysfs_emit(buf, "poolinfo - 0.1\n"); mutex_lock(&pools_lock); list_for_each_entry(pool, &dev->dma_pools, pools) { - unsigned pages = 0; - unsigned blocks = 0; - - spin_lock_irq(&pool->lock); - list_for_each_entry(page, &pool->page_list, page_list) { - pages++; - blocks += page->in_use; - } - spin_unlock_irq(&pool->lock); - /* per-pool info, no real statistics yet */ - temp = scnprintf(next, size, "%-16s %4u %4zu %4zu %2u\n", - pool->name, blocks, - pages * (pool->allocation / pool->size), - pool->size, pages); - size -= temp; - next += temp; + size += sysfs_emit_at(buf, size, "%-16s %4zu %4zu %4u %2zu\n", + pool->name, pool->nr_active, + pool->nr_blocks, pool->size, + pool->nr_pages); } mutex_unlock(&pools_lock); - return PAGE_SIZE - size; + return size; } static DEVICE_ATTR_RO(pools); +#ifdef DMAPOOL_DEBUG +static void pool_check_block(struct dma_pool *pool, struct dma_block *block, + gfp_t mem_flags) +{ + u8 *data = (void *)block; + int i; + + for (i = sizeof(struct dma_block); i < pool->size; i++) { + if (data[i] == POOL_POISON_FREED) + continue; + dev_err(pool->dev, "%s %s, %p (corrupted)\n", __func__, + pool->name, block); + + /* + * Dump the first 4 bytes even if they are not + * POOL_POISON_FREED + */ + print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, + data, pool->size, 1); + break; + } + + if (!want_init_on_alloc(mem_flags)) + memset(block, POOL_POISON_ALLOCATED, pool->size); +} + +static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma) +{ + struct dma_page *page; + + list_for_each_entry(page, &pool->page_list, page_list) { + if (dma < page->dma) + continue; + if ((dma - page->dma) < pool->allocation) + return page; + } + return NULL; +} + +static bool pool_block_err(struct dma_pool *pool, void *vaddr, dma_addr_t dma) +{ + struct dma_block *block = pool->next_block; + struct dma_page *page; + + page = pool_find_page(pool, dma); + if (!page) { + dev_err(pool->dev, "%s %s, %p/%pad (bad dma)\n", + __func__, pool->name, vaddr, &dma); + return true; + } + + while (block) { + if (block != vaddr) { + block = block->next_block; + continue; + } + dev_err(pool->dev, "%s %s, dma %pad already free\n", + __func__, pool->name, &dma); + return true; + } + + memset(vaddr, POOL_POISON_FREED, pool->size); + return false; +} + +static void pool_init_page(struct dma_pool *pool, struct dma_page *page) +{ + memset(page->vaddr, POOL_POISON_FREED, pool->allocation); +} +#else +static void pool_check_block(struct dma_pool *pool, struct dma_block *block, + gfp_t mem_flags) +{ +} + +static bool pool_block_err(struct dma_pool *pool, void *vaddr, dma_addr_t dma) +{ + if (want_init_on_free()) + memset(vaddr, 0, pool->size); + return false; +} + +static void pool_init_page(struct dma_pool *pool, struct dma_page *page) +{ +} +#endif + +static struct dma_block *pool_block_pop(struct dma_pool *pool) +{ + struct dma_block *block = pool->next_block; + + if (block) { + pool->next_block = block->next_block; + pool->nr_active++; + } + return block; +} + +static void pool_block_push(struct dma_pool *pool, struct dma_block *block, + dma_addr_t dma) +{ + block->dma = dma; + block->next_block = pool->next_block; + pool->next_block = block; +} + + /** * dma_pool_create - Creates a pool of consistent memory blocks, for dma. * @name: name of pool, for diagnostics @@ -134,15 +228,18 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev, size_t allocation; bool empty = false; + if (!dev) + return NULL; + if (align == 0) align = 1; else if (align & (align - 1)) return NULL; - if (size == 0) + if (size == 0 || size > INT_MAX) return NULL; - else if (size < 4) - size = 4; + if (size < sizeof(struct dma_block)) + size = sizeof(struct dma_block); size = ALIGN(size, align); allocation = max_t(size_t, size, PAGE_SIZE); @@ -152,7 +249,9 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev, else if ((boundary < size) || (boundary & (boundary - 1))) return NULL; - retval = kmalloc(sizeof(*retval), GFP_KERNEL); + boundary = min(boundary, allocation); + + retval = kzalloc(sizeof(*retval), GFP_KERNEL); if (!retval) return retval; @@ -165,7 +264,6 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev, retval->size = size; retval->boundary = boundary; retval->allocation = allocation; - INIT_LIST_HEAD(&retval->pools); /* @@ -202,18 +300,36 @@ EXPORT_SYMBOL(dma_pool_create); static void pool_initialise_page(struct dma_pool *pool, struct dma_page *page) { - unsigned int offset = 0; - unsigned int next_boundary = pool->boundary; + unsigned int next_boundary = pool->boundary, offset = 0; + struct dma_block *block, *first = NULL, *last = NULL; - do { - unsigned int next = offset + pool->size; - if (unlikely((next + pool->size) >= next_boundary)) { - next = next_boundary; + pool_init_page(pool, page); + while (offset + pool->size <= pool->allocation) { + if (offset + pool->size > next_boundary) { + offset = next_boundary; next_boundary += pool->boundary; + continue; } - *(int *)(page->vaddr + offset) = next; - offset = next; - } while (offset < pool->allocation); + + block = page->vaddr + offset; + block->dma = page->dma + offset; + block->next_block = NULL; + + if (last) + last->next_block = block; + else + first = block; + last = block; + + offset += pool->size; + pool->nr_blocks++; + } + + last->next_block = pool->next_block; + pool->next_block = first; + + list_add(&page->page_list, &pool->page_list); + pool->nr_pages++; } static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags) @@ -223,37 +339,15 @@ static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags) page = kmalloc(sizeof(*page), mem_flags); if (!page) return NULL; + page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation, &page->dma, mem_flags); - if (page->vaddr) { -#ifdef DMAPOOL_DEBUG - memset(page->vaddr, POOL_POISON_FREED, pool->allocation); -#endif - pool_initialise_page(pool, page); - page->in_use = 0; - page->offset = 0; - } else { + if (!page->vaddr) { kfree(page); - page = NULL; + return NULL; } - return page; -} -static inline bool is_page_busy(struct dma_page *page) -{ - return page->in_use != 0; -} - -static void pool_free_page(struct dma_pool *pool, struct dma_page *page) -{ - dma_addr_t dma = page->dma; - -#ifdef DMAPOOL_DEBUG - memset(page->vaddr, POOL_POISON_FREED, pool->allocation); -#endif - dma_free_coherent(pool->dev, pool->allocation, page->vaddr, dma); - list_del(&page->page_list); - kfree(page); + return page; } /** @@ -267,7 +361,7 @@ static void pool_free_page(struct dma_pool *pool, struct dma_page *page) void dma_pool_destroy(struct dma_pool *pool) { struct dma_page *page, *tmp; - bool empty = false; + bool empty = false, busy = false; if (unlikely(!pool)) return; @@ -275,26 +369,24 @@ void dma_pool_destroy(struct dma_pool *pool) mutex_lock(&pools_reg_lock); mutex_lock(&pools_lock); list_del(&pool->pools); - if (pool->dev && list_empty(&pool->dev->dma_pools)) + if (list_empty(&pool->dev->dma_pools)) empty = true; mutex_unlock(&pools_lock); if (empty) device_remove_file(pool->dev, &dev_attr_pools); mutex_unlock(&pools_reg_lock); + if (pool->nr_active) { + dev_err(pool->dev, "%s %s busy\n", __func__, pool->name); + busy = true; + } + list_for_each_entry_safe(page, tmp, &pool->page_list, page_list) { - if (is_page_busy(page)) { - if (pool->dev) - dev_err(pool->dev, "%s %s, %p busy\n", __func__, - pool->name, page->vaddr); - else - pr_err("%s %s, %p busy\n", __func__, - pool->name, page->vaddr); - /* leak the still-in-use consistent memory */ - list_del(&page->page_list); - kfree(page); - } else - pool_free_page(pool, page); + if (!busy) + dma_free_coherent(pool->dev, pool->allocation, + page->vaddr, page->dma); + list_del(&page->page_list); + kfree(page); } kfree(pool); @@ -314,84 +406,40 @@ EXPORT_SYMBOL(dma_pool_destroy); void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags, dma_addr_t *handle) { - unsigned long flags; + struct dma_block *block; struct dma_page *page; - size_t offset; - void *retval; + unsigned long flags; might_alloc(mem_flags); spin_lock_irqsave(&pool->lock, flags); - list_for_each_entry(page, &pool->page_list, page_list) { - if (page->offset < pool->allocation) - goto ready; - } - - /* pool_alloc_page() might sleep, so temporarily drop &pool->lock */ - spin_unlock_irqrestore(&pool->lock, flags); - - page = pool_alloc_page(pool, mem_flags & (~__GFP_ZERO)); - if (!page) - return NULL; + block = pool_block_pop(pool); + if (!block) { + /* + * pool_alloc_page() might sleep, so temporarily drop + * &pool->lock + */ + spin_unlock_irqrestore(&pool->lock, flags); - spin_lock_irqsave(&pool->lock, flags); + page = pool_alloc_page(pool, mem_flags & (~__GFP_ZERO)); + if (!page) + return NULL; - list_add(&page->page_list, &pool->page_list); - ready: - page->in_use++; - offset = page->offset; - page->offset = *(int *)(page->vaddr + offset); - retval = offset + page->vaddr; - *handle = offset + page->dma; -#ifdef DMAPOOL_DEBUG - { - int i; - u8 *data = retval; - /* page->offset is stored in first 4 bytes */ - for (i = sizeof(page->offset); i < pool->size; i++) { - if (data[i] == POOL_POISON_FREED) - continue; - if (pool->dev) - dev_err(pool->dev, "%s %s, %p (corrupted)\n", - __func__, pool->name, retval); - else - pr_err("%s %s, %p (corrupted)\n", - __func__, pool->name, retval); - - /* - * Dump the first 4 bytes even if they are not - * POOL_POISON_FREED - */ - print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, - data, pool->size, 1); - break; - } + spin_lock_irqsave(&pool->lock, flags); + pool_initialise_page(pool, page); + block = pool_block_pop(pool); } - if (!(mem_flags & __GFP_ZERO)) - memset(retval, POOL_POISON_ALLOCATED, pool->size); -#endif spin_unlock_irqrestore(&pool->lock, flags); + *handle = block->dma; + pool_check_block(pool, block, mem_flags); if (want_init_on_alloc(mem_flags)) - memset(retval, 0, pool->size); + memset(block, 0, pool->size); - return retval; + return block; } EXPORT_SYMBOL(dma_pool_alloc); -static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma) -{ - struct dma_page *page; - - list_for_each_entry(page, &pool->page_list, page_list) { - if (dma < page->dma) - continue; - if ((dma - page->dma) < pool->allocation) - return page; - } - return NULL; -} - /** * dma_pool_free - put block back into dma pool * @pool: the dma pool holding the block @@ -403,65 +451,14 @@ static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma) */ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) { - struct dma_page *page; + struct dma_block *block = vaddr; unsigned long flags; - unsigned int offset; spin_lock_irqsave(&pool->lock, flags); - page = pool_find_page(pool, dma); - if (!page) { - spin_unlock_irqrestore(&pool->lock, flags); - if (pool->dev) - dev_err(pool->dev, "%s %s, %p/%pad (bad dma)\n", - __func__, pool->name, vaddr, &dma); - else - pr_err("%s %s, %p/%pad (bad dma)\n", - __func__, pool->name, vaddr, &dma); - return; - } - - offset = vaddr - page->vaddr; - if (want_init_on_free()) - memset(vaddr, 0, pool->size); -#ifdef DMAPOOL_DEBUG - if ((dma - page->dma) != offset) { - spin_unlock_irqrestore(&pool->lock, flags); - if (pool->dev) - dev_err(pool->dev, "%s %s, %p (bad vaddr)/%pad\n", - __func__, pool->name, vaddr, &dma); - else - pr_err("%s %s, %p (bad vaddr)/%pad\n", - __func__, pool->name, vaddr, &dma); - return; + if (!pool_block_err(pool, vaddr, dma)) { + pool_block_push(pool, block, dma); + pool->nr_active--; } - { - unsigned int chain = page->offset; - while (chain < pool->allocation) { - if (chain != offset) { - chain = *(int *)(page->vaddr + chain); - continue; - } - spin_unlock_irqrestore(&pool->lock, flags); - if (pool->dev) - dev_err(pool->dev, "%s %s, dma %pad already free\n", - __func__, pool->name, &dma); - else - pr_err("%s %s, dma %pad already free\n", - __func__, pool->name, &dma); - return; - } - } - memset(vaddr, POOL_POISON_FREED, pool->size); -#endif - - page->in_use--; - *(int *)vaddr = page->offset; - page->offset = offset; - /* - * Resist a temptation to do - * if (!is_page_busy(page)) pool_free_page(pool, page); - * Better have a few empty pages hang around. - */ spin_unlock_irqrestore(&pool->lock, flags); } EXPORT_SYMBOL(dma_pool_free); |