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From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: benh@kernel.crashing.org, paulus@samba.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	sstabellini@kernel.org, Robin Murphy <robin.murphy@arm.com>,
	grant.likely@arm.com, xypron.glpk@gmx.de,
	Thierry Reding <treding@nvidia.com>,
	mingo@kernel.org, bauerman@linux.ibm.com, peterz@infradead.org,
	Greg KH <gregkh@linuxfoundation.org>,
	Saravana Kannan <saravanak@google.com>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	heikki.krogerus@linux.intel.com,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Dan Williams <dan.j.williams@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	linux-devicetree <devicetree@vger.kernel.org>,
	lkml <linux-kernel@vger.kernel.org>,
	linuxppc-dev@lists.ozlabs.org, xen-devel@lists.xenproject.org,
	Nicolas Boichat <drinkcat@chromium.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	tfiga@chromium.org, bskeggs@redhat.com, bhelgaas@google.com,
	chris@chris-wilson.co.uk, tientzu@chromium.org, daniel@ffwll.ch,
	airlied@linux.ie, dri-devel@lists.freedesktop.org,
	intel-gfx@lists.freedesktop.org, jani.nikula@linux.intel.com,
	jxgao@google.com, joonas.lahtinen@linux.intel.com,
	linux-pci@vger.kernel.org, maarten.lankhorst@linux.intel.com,
	matthew.auld@intel.com, rodrigo.vivi@intel.com,
	thomas.hellstrom@linux.intel.com
Subject: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
Date: Wed, 16 Jun 2021 11:52:37 +0800	[thread overview]
Message-ID: <20210616035240.840463-10-tientzu@chromium.org> (raw)
In-Reply-To: <20210616035240.840463-1-tientzu@chromium.org>

Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.

The restricted DMA pool is preferred if available.

Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h | 15 +++++++++++++
 kernel/dma/direct.c     | 50 ++++++++++++++++++++++++++++++-----------
 kernel/dma/swiotlb.c    | 45 +++++++++++++++++++++++++++++++++++--
 3 files changed, 95 insertions(+), 15 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..2d5ec670e064 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -156,4 +156,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+				size_t size)
+{
+	return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 		min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 }
 
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+				    size_t size)
+{
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+	    swiotlb_free(dev, page, size))
+		return;
+	dma_free_contiguous(dev, page, size);
+}
+
 static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 		gfp_t gfp)
 {
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_limit);
-	page = dma_alloc_contiguous(dev, size, gfp);
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+		page = swiotlb_alloc(dev, size);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			__dma_direct_free_pages(dev, page, size);
+			return NULL;
+		}
+	}
+
+	if (!page)
+		page = dma_alloc_contiguous(dev, size, gfp);
 	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
 		dma_free_contiguous(dev, page, size);
 		page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		gfp |= __GFP_NOWARN;
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
 		if (!page)
 			return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev))
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
 	/*
 	 * Remapping or decrypting memory may block. If either is required and
 	 * we can't block, allocate the memory from the atomic pools.
+	 * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+	 * set up another device coherent pool by shared-dma-pool and use
+	 * dma_alloc_from_dev_coherent instead.
 	 */
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
 	    !gfpflags_allow_blocking(gfp) &&
 	    (force_dma_unencrypted(dev) ||
-	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+	      !dev_is_dma_coherent(dev))) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 			return NULL;
 	}
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
 	unsigned int page_order = get_order(size);
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		/* cpu_addr is a struct page cookie, not a kernel address */
 		dma_free_contiguous(dev, cpu_addr, size);
 		return;
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev)) {
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev)) {
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 		return;
 	}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
 	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
 		arch_dma_clear_uncached(cpu_addr, size);
 
-	dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
 
 struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	void *ret;
 
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
 	return page;
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
 	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
 
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 }
 
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index fec4934b9926..6ad85b48f101 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -462,8 +462,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 
 	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
 	do {
-		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
-		    (orig_addr & iotlb_align_mask)) {
+		if (orig_addr &&
+		    (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+			    (orig_addr & iotlb_align_mask)) {
 			index = wrap_index(mem, index + 1);
 			continue;
 		}
@@ -702,3 +703,43 @@ static int __init swiotlb_create_default_debugfs(void)
 late_initcall(swiotlb_create_default_debugfs);
 
 #endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+	phys_addr_t tlb_addr;
+	int index;
+
+	/*
+	 * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+	 * coherent allocation. Otherwise might break existing devices.
+	 * One must set up another device coherent pool by shared-dma-pool and
+	 * use dma_alloc_from_dev_coherent instead for atomic coherent
+	 * allocation to avoid memory remapping.
+	 */
+	if (!mem || mem == io_tlb_default_mem)
+		return NULL;
+
+	index = swiotlb_find_slots(dev, 0, size);
+	if (index == -1)
+		return NULL;
+
+	tlb_addr = slot_addr(mem->start, index);
+
+	return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+	phys_addr_t tlb_addr = page_to_phys(page);
+
+	if (!is_swiotlb_buffer(dev, tlb_addr))
+		return false;
+
+	swiotlb_release_slots(dev, tlb_addr);
+
+	return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org,
	chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org,
	mingo@kernel.org, jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	daniel@ffwll.ch, airlied@linux.ie,
	maarten.lankhorst@linux.intel.com, linuxppc-dev@lists.ozlabs.org,
	jani.nikula@linux.intel.com,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Robin Murphy <robin.murphy@arm.com>,
	bauerman@linux.ibm.com
Subject: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
Date: Wed, 16 Jun 2021 11:52:37 +0800	[thread overview]
Message-ID: <20210616035240.840463-10-tientzu@chromium.org> (raw)
In-Reply-To: <20210616035240.840463-1-tientzu@chromium.org>

Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.

The restricted DMA pool is preferred if available.

Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h | 15 +++++++++++++
 kernel/dma/direct.c     | 50 ++++++++++++++++++++++++++++++-----------
 kernel/dma/swiotlb.c    | 45 +++++++++++++++++++++++++++++++++++--
 3 files changed, 95 insertions(+), 15 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..2d5ec670e064 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -156,4 +156,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+				size_t size)
+{
+	return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 		min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 }
 
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+				    size_t size)
+{
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+	    swiotlb_free(dev, page, size))
+		return;
+	dma_free_contiguous(dev, page, size);
+}
+
 static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 		gfp_t gfp)
 {
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_limit);
-	page = dma_alloc_contiguous(dev, size, gfp);
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+		page = swiotlb_alloc(dev, size);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			__dma_direct_free_pages(dev, page, size);
+			return NULL;
+		}
+	}
+
+	if (!page)
+		page = dma_alloc_contiguous(dev, size, gfp);
 	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
 		dma_free_contiguous(dev, page, size);
 		page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		gfp |= __GFP_NOWARN;
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
 		if (!page)
 			return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev))
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
 	/*
 	 * Remapping or decrypting memory may block. If either is required and
 	 * we can't block, allocate the memory from the atomic pools.
+	 * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+	 * set up another device coherent pool by shared-dma-pool and use
+	 * dma_alloc_from_dev_coherent instead.
 	 */
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
 	    !gfpflags_allow_blocking(gfp) &&
 	    (force_dma_unencrypted(dev) ||
-	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+	      !dev_is_dma_coherent(dev))) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 			return NULL;
 	}
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
 	unsigned int page_order = get_order(size);
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		/* cpu_addr is a struct page cookie, not a kernel address */
 		dma_free_contiguous(dev, cpu_addr, size);
 		return;
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev)) {
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev)) {
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 		return;
 	}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
 	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
 		arch_dma_clear_uncached(cpu_addr, size);
 
-	dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
 
 struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	void *ret;
 
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
 	return page;
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
 	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
 
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 }
 
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index fec4934b9926..6ad85b48f101 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -462,8 +462,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 
 	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
 	do {
-		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
-		    (orig_addr & iotlb_align_mask)) {
+		if (orig_addr &&
+		    (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+			    (orig_addr & iotlb_align_mask)) {
 			index = wrap_index(mem, index + 1);
 			continue;
 		}
@@ -702,3 +703,43 @@ static int __init swiotlb_create_default_debugfs(void)
 late_initcall(swiotlb_create_default_debugfs);
 
 #endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+	phys_addr_t tlb_addr;
+	int index;
+
+	/*
+	 * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+	 * coherent allocation. Otherwise might break existing devices.
+	 * One must set up another device coherent pool by shared-dma-pool and
+	 * use dma_alloc_from_dev_coherent instead for atomic coherent
+	 * allocation to avoid memory remapping.
+	 */
+	if (!mem || mem == io_tlb_default_mem)
+		return NULL;
+
+	index = swiotlb_find_slots(dev, 0, size);
+	if (index == -1)
+		return NULL;
+
+	tlb_addr = slot_addr(mem->start, index);
+
+	return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+	phys_addr_t tlb_addr = page_to_phys(page);
+
+	if (!is_swiotlb_buffer(dev, tlb_addr))
+		return false;
+
+	swiotlb_release_slots(dev, tlb_addr);
+
+	return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	benh@kernel.crashing.org, joonas.lahtinen@linux.intel.com,
	dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk,
	grant.likely@arm.com, paulus@samba.org, mingo@kernel.org,
	jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	daniel@ffwll.ch, airlied@linux.ie,
	maarten.lankhorst@linux.intel.com, linuxppc-dev@lists.ozlabs.org,
	jani.nikula@linux.intel.com,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Robin Murphy <robin.murphy@arm.com>,
	bauerman@linux.ibm.com
Subject: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
Date: Wed, 16 Jun 2021 11:52:37 +0800	[thread overview]
Message-ID: <20210616035240.840463-10-tientzu@chromium.org> (raw)
In-Reply-To: <20210616035240.840463-1-tientzu@chromium.org>

Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.

The restricted DMA pool is preferred if available.

Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h | 15 +++++++++++++
 kernel/dma/direct.c     | 50 ++++++++++++++++++++++++++++++-----------
 kernel/dma/swiotlb.c    | 45 +++++++++++++++++++++++++++++++++++--
 3 files changed, 95 insertions(+), 15 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..2d5ec670e064 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -156,4 +156,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+				size_t size)
+{
+	return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 		min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 }
 
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+				    size_t size)
+{
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+	    swiotlb_free(dev, page, size))
+		return;
+	dma_free_contiguous(dev, page, size);
+}
+
 static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 		gfp_t gfp)
 {
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_limit);
-	page = dma_alloc_contiguous(dev, size, gfp);
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+		page = swiotlb_alloc(dev, size);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			__dma_direct_free_pages(dev, page, size);
+			return NULL;
+		}
+	}
+
+	if (!page)
+		page = dma_alloc_contiguous(dev, size, gfp);
 	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
 		dma_free_contiguous(dev, page, size);
 		page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		gfp |= __GFP_NOWARN;
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
 		if (!page)
 			return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev))
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
 	/*
 	 * Remapping or decrypting memory may block. If either is required and
 	 * we can't block, allocate the memory from the atomic pools.
+	 * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+	 * set up another device coherent pool by shared-dma-pool and use
+	 * dma_alloc_from_dev_coherent instead.
 	 */
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
 	    !gfpflags_allow_blocking(gfp) &&
 	    (force_dma_unencrypted(dev) ||
-	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+	      !dev_is_dma_coherent(dev))) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 			return NULL;
 	}
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
 	unsigned int page_order = get_order(size);
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		/* cpu_addr is a struct page cookie, not a kernel address */
 		dma_free_contiguous(dev, cpu_addr, size);
 		return;
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev)) {
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev)) {
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 		return;
 	}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
 	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
 		arch_dma_clear_uncached(cpu_addr, size);
 
-	dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
 
 struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	void *ret;
 
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
 	return page;
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
 	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
 
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 }
 
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index fec4934b9926..6ad85b48f101 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -462,8 +462,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 
 	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
 	do {
-		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
-		    (orig_addr & iotlb_align_mask)) {
+		if (orig_addr &&
+		    (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+			    (orig_addr & iotlb_align_mask)) {
 			index = wrap_index(mem, index + 1);
 			continue;
 		}
@@ -702,3 +703,43 @@ static int __init swiotlb_create_default_debugfs(void)
 late_initcall(swiotlb_create_default_debugfs);
 
 #endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+	phys_addr_t tlb_addr;
+	int index;
+
+	/*
+	 * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+	 * coherent allocation. Otherwise might break existing devices.
+	 * One must set up another device coherent pool by shared-dma-pool and
+	 * use dma_alloc_from_dev_coherent instead for atomic coherent
+	 * allocation to avoid memory remapping.
+	 */
+	if (!mem || mem == io_tlb_default_mem)
+		return NULL;
+
+	index = swiotlb_find_slots(dev, 0, size);
+	if (index == -1)
+		return NULL;
+
+	tlb_addr = slot_addr(mem->start, index);
+
+	return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+	phys_addr_t tlb_addr = page_to_phys(page);
+
+	if (!is_swiotlb_buffer(dev, tlb_addr))
+		return false;
+
+	swiotlb_release_slots(dev, tlb_addr);
+
+	return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
-- 
2.32.0.272.g935e593368-goog

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

WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk,
	grant.likely@arm.com, paulus@samba.org, mingo@kernel.org,
	jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	airlied@linux.ie, Robin Murphy <robin.murphy@arm.com>,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	linuxppc-dev@lists.ozlabs.org, bauerman@linux.ibm.com
Subject: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
Date: Wed, 16 Jun 2021 11:52:37 +0800	[thread overview]
Message-ID: <20210616035240.840463-10-tientzu@chromium.org> (raw)
In-Reply-To: <20210616035240.840463-1-tientzu@chromium.org>

Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.

The restricted DMA pool is preferred if available.

Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h | 15 +++++++++++++
 kernel/dma/direct.c     | 50 ++++++++++++++++++++++++++++++-----------
 kernel/dma/swiotlb.c    | 45 +++++++++++++++++++++++++++++++++++--
 3 files changed, 95 insertions(+), 15 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..2d5ec670e064 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -156,4 +156,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+				size_t size)
+{
+	return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 		min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 }
 
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+				    size_t size)
+{
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+	    swiotlb_free(dev, page, size))
+		return;
+	dma_free_contiguous(dev, page, size);
+}
+
 static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 		gfp_t gfp)
 {
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_limit);
-	page = dma_alloc_contiguous(dev, size, gfp);
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+		page = swiotlb_alloc(dev, size);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			__dma_direct_free_pages(dev, page, size);
+			return NULL;
+		}
+	}
+
+	if (!page)
+		page = dma_alloc_contiguous(dev, size, gfp);
 	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
 		dma_free_contiguous(dev, page, size);
 		page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		gfp |= __GFP_NOWARN;
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
 		if (!page)
 			return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev))
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
 	/*
 	 * Remapping or decrypting memory may block. If either is required and
 	 * we can't block, allocate the memory from the atomic pools.
+	 * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+	 * set up another device coherent pool by shared-dma-pool and use
+	 * dma_alloc_from_dev_coherent instead.
 	 */
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
 	    !gfpflags_allow_blocking(gfp) &&
 	    (force_dma_unencrypted(dev) ||
-	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+	      !dev_is_dma_coherent(dev))) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 			return NULL;
 	}
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
 	unsigned int page_order = get_order(size);
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		/* cpu_addr is a struct page cookie, not a kernel address */
 		dma_free_contiguous(dev, cpu_addr, size);
 		return;
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev)) {
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev)) {
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 		return;
 	}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
 	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
 		arch_dma_clear_uncached(cpu_addr, size);
 
-	dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
 
 struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	void *ret;
 
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
 	return page;
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
 	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
 
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 }
 
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index fec4934b9926..6ad85b48f101 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -462,8 +462,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 
 	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
 	do {
-		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
-		    (orig_addr & iotlb_align_mask)) {
+		if (orig_addr &&
+		    (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+			    (orig_addr & iotlb_align_mask)) {
 			index = wrap_index(mem, index + 1);
 			continue;
 		}
@@ -702,3 +703,43 @@ static int __init swiotlb_create_default_debugfs(void)
 late_initcall(swiotlb_create_default_debugfs);
 
 #endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+	phys_addr_t tlb_addr;
+	int index;
+
+	/*
+	 * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+	 * coherent allocation. Otherwise might break existing devices.
+	 * One must set up another device coherent pool by shared-dma-pool and
+	 * use dma_alloc_from_dev_coherent instead for atomic coherent
+	 * allocation to avoid memory remapping.
+	 */
+	if (!mem || mem == io_tlb_default_mem)
+		return NULL;
+
+	index = swiotlb_find_slots(dev, 0, size);
+	if (index == -1)
+		return NULL;
+
+	tlb_addr = slot_addr(mem->start, index);
+
+	return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+	phys_addr_t tlb_addr = page_to_phys(page);
+
+	if (!is_swiotlb_buffer(dev, tlb_addr))
+		return false;
+
+	swiotlb_release_slots(dev, tlb_addr);
+
+	return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	benh@kernel.crashing.org, dri-devel@lists.freedesktop.org,
	chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org,
	mingo@kernel.org, jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	airlied@linux.ie, Robin Murphy <robin.murphy@arm.com>,
	Nicolas Boichat <drinkcat@chromium.org>,
	bhelgaas@google.com, tientzu@chromium.org,
	Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	linuxppc-dev@lists.ozlabs.org, bauerman@linux.ibm.com
Subject: [Intel-gfx] [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support
Date: Wed, 16 Jun 2021 11:52:37 +0800	[thread overview]
Message-ID: <20210616035240.840463-10-tientzu@chromium.org> (raw)
In-Reply-To: <20210616035240.840463-1-tientzu@chromium.org>

Add the functions, swiotlb_{alloc,free} to support the memory allocation
from restricted DMA pool.

The restricted DMA pool is preferred if available.

Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h | 15 +++++++++++++
 kernel/dma/direct.c     | 50 ++++++++++++++++++++++++++++++-----------
 kernel/dma/swiotlb.c    | 45 +++++++++++++++++++++++++++++++++++--
 3 files changed, 95 insertions(+), 15 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index efcd56e3a16c..2d5ec670e064 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -156,4 +156,19 @@ static inline void swiotlb_adjust_size(unsigned long size)
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+				size_t size)
+{
+	return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 3713461d6fe0..da0e09621230 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 		min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 }
 
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+				    size_t size)
+{
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+	    swiotlb_free(dev, page, size))
+		return;
+	dma_free_contiguous(dev, page, size);
+}
+
 static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 		gfp_t gfp)
 {
@@ -86,7 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
 
 	gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
 					   &phys_limit);
-	page = dma_alloc_contiguous(dev, size, gfp);
+	if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) {
+		page = swiotlb_alloc(dev, size);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			__dma_direct_free_pages(dev, page, size);
+			return NULL;
+		}
+	}
+
+	if (!page)
+		page = dma_alloc_contiguous(dev, size, gfp);
 	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
 		dma_free_contiguous(dev, page, size);
 		page = NULL;
@@ -142,7 +160,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 		gfp |= __GFP_NOWARN;
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
 		if (!page)
 			return NULL;
@@ -155,18 +173,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev))
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev))
 		return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
 	/*
 	 * Remapping or decrypting memory may block. If either is required and
 	 * we can't block, allocate the memory from the atomic pools.
+	 * If restricted DMA (i.e., is_dev_swiotlb_force) is required, one must
+	 * set up another device coherent pool by shared-dma-pool and use
+	 * dma_alloc_from_dev_coherent instead.
 	 */
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
 	    !gfpflags_allow_blocking(gfp) &&
 	    (force_dma_unencrypted(dev) ||
-	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+	     (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+	      !dev_is_dma_coherent(dev))) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	/* we always manually zero the memory once we are done */
@@ -237,7 +260,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
 			return NULL;
 	}
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -247,15 +270,15 @@ void dma_direct_free(struct device *dev, size_t size,
 	unsigned int page_order = get_order(size);
 
 	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
-	    !force_dma_unencrypted(dev)) {
+	    !force_dma_unencrypted(dev) && !is_dev_swiotlb_force(dev)) {
 		/* cpu_addr is a struct page cookie, not a kernel address */
 		dma_free_contiguous(dev, cpu_addr, size);
 		return;
 	}
 
 	if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
-	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
-	    !dev_is_dma_coherent(dev)) {
+	    !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+	    !is_dev_swiotlb_force(dev)) {
 		arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
 		return;
 	}
@@ -273,7 +296,7 @@ void dma_direct_free(struct device *dev, size_t size,
 	else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
 		arch_dma_clear_uncached(cpu_addr, size);
 
-	dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+	__dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
 }
 
 struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +306,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	void *ret;
 
 	if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
-	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+	    force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+	    !is_dev_swiotlb_force(dev))
 		return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
 
 	page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +334,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
 	*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
 	return page;
 out_free_pages:
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 	return NULL;
 }
 
@@ -329,7 +353,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
 	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
 
-	dma_free_contiguous(dev, page, size);
+	__dma_direct_free_pages(dev, page, size);
 }
 
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index fec4934b9926..6ad85b48f101 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -462,8 +462,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
 
 	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
 	do {
-		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
-		    (orig_addr & iotlb_align_mask)) {
+		if (orig_addr &&
+		    (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+			    (orig_addr & iotlb_align_mask)) {
 			index = wrap_index(mem, index + 1);
 			continue;
 		}
@@ -702,3 +703,43 @@ static int __init swiotlb_create_default_debugfs(void)
 late_initcall(swiotlb_create_default_debugfs);
 
 #endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+	phys_addr_t tlb_addr;
+	int index;
+
+	/*
+	 * Skip io_tlb_default_mem since swiotlb_alloc doesn't support atomic
+	 * coherent allocation. Otherwise might break existing devices.
+	 * One must set up another device coherent pool by shared-dma-pool and
+	 * use dma_alloc_from_dev_coherent instead for atomic coherent
+	 * allocation to avoid memory remapping.
+	 */
+	if (!mem || mem == io_tlb_default_mem)
+		return NULL;
+
+	index = swiotlb_find_slots(dev, 0, size);
+	if (index == -1)
+		return NULL;
+
+	tlb_addr = slot_addr(mem->start, index);
+
+	return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+	phys_addr_t tlb_addr = page_to_phys(page);
+
+	if (!is_swiotlb_buffer(dev, tlb_addr))
+		return false;
+
+	swiotlb_release_slots(dev, tlb_addr);
+
+	return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
-- 
2.32.0.272.g935e593368-goog

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

  parent reply	other threads:[~2021-06-16  3:54 UTC|newest]

Thread overview: 92+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-16  3:52 [Intel-gfx] [PATCH v11 00/12] Restricted DMA Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 01/12] swiotlb: Refactor swiotlb init functions Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 02/12] swiotlb: Refactor swiotlb_create_debugfs Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 05/12] swiotlb: Update is_swiotlb_active " Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 06/12] swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 07/12] swiotlb: Move alloc_size to swiotlb_find_slots Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single Claire Chang
2021-06-16  3:52 ` Claire Chang [this message]
2021-06-16  4:04   ` [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support Claire Chang
2021-06-16  4:59     ` [Intel-gfx] " Christoph Hellwig
2021-06-16  5:10       ` Claire Chang
2021-06-16  5:18         ` [Intel-gfx] " Christoph Hellwig
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 10/12] swiotlb: Add restricted DMA pool initialization Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 11/12] dt-bindings: of: Add restricted DMA pool Claire Chang
2021-06-16  3:52 ` [Intel-gfx] [PATCH v11 12/12] of: Add plumbing for " Claire Chang
2021-06-16  6:25 ` [PATCH v11 00/12] Restricted DMA Claire Chang
2021-06-16  7:34 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork

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