[PATCHv3 02/12] dmapool: remove checks for dev == NULL

From: Keith Busch
Date: Tue Jan 03 2023 - 14:19:34 EST


From: Tony Battersby <tonyb@xxxxxxxxxxxxxxx>

dmapool originally tried to support pools without a device because
dma_alloc_coherent() supports allocations without a device. But nobody
ended up using dma pools without a device, and trying to do so will
result in an oops. So remove the checks for pool->dev == NULL since they
are unneeded bloat.

Signed-off-by: Tony Battersby <tonyb@xxxxxxxxxxxxxxx>
[added check for null dev on create]
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
mm/dmapool.c | 45 ++++++++++++++-------------------------------
1 file changed, 14 insertions(+), 31 deletions(-)

diff --git a/mm/dmapool.c b/mm/dmapool.c
index a7eb5d0eb2da7..559207e1c3339 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -134,6 +134,9 @@ 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))
@@ -275,7 +278,7 @@ 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)
@@ -284,12 +287,8 @@ void dma_pool_destroy(struct dma_pool *pool)

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);
+ dev_err(pool->dev, "%s %s, %p busy\n", __func__,
+ pool->name, page->vaddr);
/* leak the still-in-use consistent memory */
list_del(&page->page_list);
kfree(page);
@@ -351,12 +350,8 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
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);
+ dev_err(pool->dev, "%s %s, %p (corrupted)\n",
+ __func__, pool->name, retval);

/*
* Dump the first 4 bytes even if they are not
@@ -411,12 +406,8 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
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);
+ dev_err(pool->dev, "%s %s, %p/%pad (bad dma)\n",
+ __func__, pool->name, vaddr, &dma);
return;
}

@@ -426,12 +417,8 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
#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);
+ dev_err(pool->dev, "%s %s, %p (bad vaddr)/%pad\n",
+ __func__, pool->name, vaddr, &dma);
return;
}
{
@@ -442,12 +429,8 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
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);
+ dev_err(pool->dev, "%s %s, dma %pad already free\n",
+ __func__, pool->name, &dma);
return;
}
}
--
2.30.2