From 52e7d56539794b20fb9458c06292dfd24bba6a2d Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 26 Jan 2023 13:51:19 -0800 Subject: dmapool: move debug code to own functions Clean up the normal path by moving the debug code outside it. Link: https://lkml.kernel.org/r/20230126215125.4069751-7-kbusch@meta.com Signed-off-by: Keith Busch Reviewed-by: Christoph Hellwig Cc: Matthew Wilcox Cc: Tony Battersby Signed-off-by: Andrew Morton --- mm/dmapool.c | 128 +++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 77 insertions(+), 51 deletions(-) (limited to 'mm') diff --git a/mm/dmapool.c b/mm/dmapool.c index eaed3ffb42aa..30b069e99996 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -96,6 +96,78 @@ static ssize_t pools_show(struct device *dev, struct device_attribute *attr, cha static DEVICE_ATTR_RO(pools); +#ifdef DMAPOOL_DEBUG +static void pool_check_block(struct dma_pool *pool, void *retval, + unsigned int offset, gfp_t mem_flags) +{ + int i; + u8 *data = retval; + /* page->offset is stored in first 4 bytes */ + for (i = sizeof(offset); i < pool->size; i++) { + if (data[i] == POOL_POISON_FREED) + continue; + dev_err(pool->dev, "%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; + } + if (!want_init_on_alloc(mem_flags)) + memset(retval, POOL_POISON_ALLOCATED, pool->size); +} + +static bool pool_page_err(struct dma_pool *pool, struct dma_page *page, + void *vaddr, dma_addr_t dma) +{ + unsigned int offset = vaddr - page->vaddr; + unsigned int chain = page->offset; + + if ((dma - page->dma) != offset) { + dev_err(pool->dev, "%s %s, %p (bad vaddr)/%pad\n", + __func__, pool->name, vaddr, &dma); + return true; + } + + while (chain < pool->allocation) { + if (chain != offset) { + chain = *(int *)(page->vaddr + chain); + 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, void *retval, + unsigned int offset, gfp_t mem_flags) + +{ +} + +static bool pool_page_err(struct dma_pool *pool, struct dma_page *page, + void *vaddr, dma_addr_t dma) +{ + return false; +} + +static void pool_init_page(struct dma_pool *pool, struct dma_page *page) +{ +} +#endif + /** * dma_pool_create - Creates a pool of consistent memory blocks, for dma. * @name: name of pool, for diagnostics @@ -223,9 +295,7 @@ static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags) 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_init_page(pool, page); pool_initialise_page(pool, page); page->in_use = 0; page->offset = 0; @@ -245,9 +315,7 @@ 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 + pool_init_page(pool, page); dma_free_coherent(pool->dev, pool->allocation, page->vaddr, dma); list_del(&page->page_list); kfree(page); @@ -336,29 +404,7 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags, 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; - dev_err(pool->dev, "%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; - } - } - if (!want_init_on_alloc(mem_flags)) - memset(retval, POOL_POISON_ALLOCATED, pool->size); -#endif + pool_check_block(pool, retval, offset, mem_flags); spin_unlock_irqrestore(&pool->lock, flags); if (want_init_on_alloc(mem_flags)) @@ -394,7 +440,6 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) { struct dma_page *page; unsigned long flags; - unsigned int offset; spin_lock_irqsave(&pool->lock, flags); page = pool_find_page(pool, dma); @@ -405,35 +450,16 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) return; } - offset = vaddr - page->vaddr; if (want_init_on_free()) memset(vaddr, 0, pool->size); -#ifdef DMAPOOL_DEBUG - if ((dma - page->dma) != offset) { + if (pool_page_err(pool, page, vaddr, dma)) { spin_unlock_irqrestore(&pool->lock, flags); - dev_err(pool->dev, "%s %s, %p (bad vaddr)/%pad\n", - __func__, pool->name, vaddr, &dma); return; } - { - unsigned int chain = page->offset; - while (chain < pool->allocation) { - if (chain != offset) { - chain = *(int *)(page->vaddr + chain); - continue; - } - spin_unlock_irqrestore(&pool->lock, flags); - dev_err(pool->dev, "%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; + page->offset = vaddr - page->vaddr; /* * Resist a temptation to do * if (!is_page_busy(page)) pool_free_page(pool, page); -- cgit v1.2.3