Linux IOMMU Development
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: iommu@lists.linux-foundation.org
Cc: Robin Murphy <robin.murphy@arm.com>,
	David Rientjes <rientjes@google.com>
Subject: [PATCH 07/10] dma-direct: warn if there is no pool for force unencrypted allocations
Date: Thu, 21 Oct 2021 11:06:08 +0200	[thread overview]
Message-ID: <20211021090611.488281-8-hch@lst.de> (raw)
In-Reply-To: <20211021090611.488281-1-hch@lst.de>

Instead of blindly running into a blocking operation for a non-blocking gfp,
return NULL and spew an error.  Note that Kconfig prevents this for all
currently relevant platforms, and this is just a debug check.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 kernel/dma/direct.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index d66f37f34ba71..680fe10410645 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -154,6 +154,9 @@ static void *dma_direct_alloc_from_pool(struct device *dev, size_t size,
 	u64 phys_mask;
 	void *ret;
 
+	if (WARN_ON_ONCE(!IS_ENABLED(CONFIG_DMA_COHERENT_POOL)))
+		return NULL;
+
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_mask);
 	page = dma_alloc_from_pool(dev, size, &ret, gfp, dma_coherent_ok);
@@ -234,8 +237,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	 * Decrypting memory may block, so allocate the memory from the atomic
 	 * pools if we can't block.
 	 */
-	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
 	    !is_swiotlb_for_alloc(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
@@ -353,8 +355,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	struct page *page;
 	void *ret;
 
-	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	if (force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
 	    !is_swiotlb_for_alloc(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
-- 
2.30.2

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  parent reply	other threads:[~2021-10-21  9:06 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-21  9:06 dma-direct fixes and cleanups v2 Christoph Hellwig
2021-10-21  9:06 ` [PATCH 01/10] dma-direct: factor out dma_set_{de,en}crypted helpers Christoph Hellwig
2021-11-04 12:35   ` Robin Murphy
2021-10-21  9:06 ` [PATCH 02/10] dma-direct: unmapped remapped pages when dma_set_decrypted Christoph Hellwig
2021-11-04 12:35   ` Robin Murphy
2021-11-09 14:10     ` Christoph Hellwig
2021-11-09 14:27       ` Robin Murphy
2021-10-21  9:06 ` [PATCH 03/10] dma-direct: leak memory that can't be re-encrypted Christoph Hellwig
2021-11-04 12:35   ` Robin Murphy
2021-11-09 14:19     ` Christoph Hellwig
2021-10-21  9:06 ` [PATCH 04/10] dma-direct: clean up the remapping checks in dma_direct_alloc Christoph Hellwig
2021-11-04 12:35   ` Robin Murphy
2021-11-09 14:23     ` Christoph Hellwig
2021-10-21  9:06 ` [PATCH 05/10] dma-direct: factor out a helper for DMA_ATTR_NO_KERNEL_MAPPING allocations Christoph Hellwig
2021-11-04 12:36   ` Robin Murphy
2021-11-09 14:25     ` Christoph Hellwig
2021-11-09 14:39       ` Robin Murphy
2021-10-21  9:06 ` [PATCH 06/10] dma-direct: refactor the !coherent checks in dma_direct_alloc Christoph Hellwig
2021-11-04 12:36   ` Robin Murphy
2021-11-09 14:27     ` Christoph Hellwig
2021-10-21  9:06 ` Christoph Hellwig [this message]
2021-11-04 12:36   ` [PATCH 07/10] dma-direct: warn if there is no pool for force unencrypted allocations Robin Murphy
2021-10-21  9:06 ` [PATCH 08/10] dma-direct: drop two CONFIG_DMA_RESTRICTED_POOL conditionals Christoph Hellwig
2021-11-04 12:37   ` Robin Murphy
2021-10-21  9:06 ` [PATCH 09/10] dma-direct: factor the swiotlb code out of __dma_direct_alloc_pages Christoph Hellwig
2021-11-04 12:37   ` Robin Murphy
2021-10-21  9:06 ` [PATCH 10/10] dma-direct: add a dma_direct_use_pool helper Christoph Hellwig
2021-11-04 12:37   ` Robin Murphy
2021-11-04  8:54 ` dma-direct fixes and cleanups v2 Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211021090611.488281-8-hch@lst.de \
    --to=hch@lst.de \
    --cc=iommu@lists.linux-foundation.org \
    --cc=rientjes@google.com \
    --cc=robin.murphy@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox