[PATCH v5 00/11] IOMMU memory observability

[PATCH v5 00/11] IOMMU memory observability

[Pasha Tatashin]

----------------------------------------------------------------------
Changelog
----------------------------------------------------------------------
v5:
- Synced with v6.8-rc5
- Added: Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
- Added: Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
- Addressed review comments from Robin Murphy:
  Updated the header comment in iommu-pages.h
  Removed __iommu_alloc_pages_node(), invoke
  iommu_alloc_pages_node directly.
  Removed unused: __iommu_alloc_page_node()
  Removed __iommu_free_page()
  Renamed: iommu_free_pages_list() -> iommu_put_pages_list()
  Added missing iommu_put_pages_list() to dma-iommu.c in
  iommu/dma: use iommu_put_pages_list() to releae freelist

v4:
- Synced with v6.8-rc3
- Updated commit log for "iommu: account IOMMU allocated memory" as
  suggested by Michal Koutný
- Added more Acked-bys David Rientjes and Thierry Reding
- Added Tested-by Bagas Sanjaya.

v3:
- Sync with v6.7-rc7
- Addressed comments from David Rientjes: s/pages/page/, added
  unlikely() into the branches, expanded comment for
  iommu_free_pages_list().
- Added Acked-bys: David Rientjes

v2:
- Added Reviewed-by Janne Grunau
- Sync with 6.7.0-rc3
- Separated form the series patches:
vhost-vdpa: account iommu allocations
https://lore.kernel.org/all/20231130200447.2319543-1-pasha.tatashin@soleen.com
vfio: account iommu allocations
https://lore.kernel.org/all/20231130200900.2320829-1-pasha.tatashin@soleen.com
as suggested by Jason Gunthorpe
- Fixed SPARC build issue detected by kernel test robot
- Drop the following patches as they do account iommu page tables:
iommu/dma: use page allocation function provided by iommu-pages.h
iommu/fsl: use page allocation function provided by iommu-pages.h
iommu/iommufd: use page allocation function provided by iommu-pages.h
as suggested by Robin Murphy. These patches are not related to IOMMU
page tables. We might need to do a separate work to support DMA
observability.
- Remove support iommu/io-pgtable-arm-v7s as the 2nd level pages are
under a page size, thanks Robin Murphy for pointing this out.

----------------------------------------------------------------------
Description
----------------------------------------------------------------------
IOMMU subsystem may contain state that is in gigabytes. Majority of that
state is iommu page tables. Yet, there is currently, no way to observe
how much memory is actually used by the iommu subsystem.

This patch series solves this problem by adding both observability to
all pages that are allocated by IOMMU, and also accountability, so
admins can limit the amount if via cgroups.

The system-wide observability is using /proc/meminfo:
SecPageTables:    438176 kB

Contains IOMMU and KVM memory.

Per-node observability:
/sys/devices/system/node/nodeN/meminfo
Node N SecPageTables:    422204 kB

Contains IOMMU and KVM memory in the given NUMA node.

Per-node IOMMU only observability:
/sys/devices/system/node/nodeN/vmstat
nr_iommu_pages 105555

Contains number of pages IOMMU allocated in the given node.

Accountability: using sec_pagetables cgroup-v2 memory.stat entry.

With the change, iova_stress[1] stops as limit is reached:

$ ./iova_stress
iova space:     0T      free memory:   497G
iova space:     1T      free memory:   495G
iova space:     2T      free memory:   493G
iova space:     3T      free memory:   491G

stops as limit is reached.

This series encorporates suggestions that came from the discussion
at LPC [2].
----------------------------------------------------------------------
[1] https://github.com/soleen/iova_stress
[2] https://lpc.events/event/17/contributions/1466
----------------------------------------------------------------------
Previous versions
v1: https://lore.kernel.org/all/20231128204938.1453583-1-pasha.tatashin@soleen.com
v2: https://lore.kernel.org/linux-mm/20231130201504.2322355-1-pasha.tatashin@soleen.com
v3: https://lore.kernel.org/all/20231226200205.562565-1-pasha.tatashin@soleen.com
v4: https://lore.kernel.org/all/20240207174102.1486130-1-pasha.tatashin@soleen.com
----------------------------------------------------------------------

Pasha Tatashin (11):
  iommu/vt-d: add wrapper functions for page allocations
  iommu/dma: use iommu_put_pages_list() to releae freelist
  iommu/amd: use page allocation function provided by iommu-pages.h
  iommu/io-pgtable-arm: use page allocation function provided by
    iommu-pages.h
  iommu/io-pgtable-dart: use page allocation function provided by
    iommu-pages.h
  iommu/exynos: use page allocation function provided by iommu-pages.h
  iommu/rockchip: use page allocation function provided by iommu-pages.h
  iommu/sun50i: use page allocation function provided by iommu-pages.h
  iommu/tegra-smmu: use page allocation function provided by
    iommu-pages.h
  iommu: observability of the IOMMU allocations
  iommu: account IOMMU allocated memory

 Documentation/admin-guide/cgroup-v2.rst |   2 +-
 Documentation/filesystems/proc.rst      |   4 +-
 drivers/iommu/amd/amd_iommu.h           |   8 -
 drivers/iommu/amd/init.c                |  91 ++++++------
 drivers/iommu/amd/io_pgtable.c          |  13 +-
 drivers/iommu/amd/io_pgtable_v2.c       |  20 +--
 drivers/iommu/amd/iommu.c               |  13 +-
 drivers/iommu/dma-iommu.c               |   7 +-
 drivers/iommu/exynos-iommu.c            |  14 +-
 drivers/iommu/intel/dmar.c              |  16 +-
 drivers/iommu/intel/iommu.c             |  47 ++----
 drivers/iommu/intel/iommu.h             |   2 -
 drivers/iommu/intel/irq_remapping.c     |  16 +-
 drivers/iommu/intel/pasid.c             |  18 +--
 drivers/iommu/intel/svm.c               |  11 +-
 drivers/iommu/io-pgtable-arm.c          |  15 +-
 drivers/iommu/io-pgtable-dart.c         |  37 ++---
 drivers/iommu/iommu-pages.h             | 186 ++++++++++++++++++++++++
 drivers/iommu/rockchip-iommu.c          |  14 +-
 drivers/iommu/sun50i-iommu.c            |   7 +-
 drivers/iommu/tegra-smmu.c              |  18 ++-
 include/linux/mmzone.h                  |   5 +-
 mm/vmstat.c                             |   3 +
 23 files changed, 361 insertions(+), 206 deletions(-)
 create mode 100644 drivers/iommu/iommu-pages.h

-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 01/11] iommu/vt-d: add wrapper functions for page allocations

[Pasha Tatashin]

In order to improve observability and accountability of IOMMU layer, we
must account the number of pages that are allocated by functions that
are calling directly into buddy allocator.

This is achieved by first wrapping the allocation related functions into a
separate inline functions in new file:

drivers/iommu/iommu-pages.h

Convert all page allocation calls under iommu/intel to use these new
functions.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/intel/dmar.c          |  16 +--
 drivers/iommu/intel/iommu.c         |  47 +++------
 drivers/iommu/intel/iommu.h         |   2 -
 drivers/iommu/intel/irq_remapping.c |  16 +--
 drivers/iommu/intel/pasid.c         |  18 ++--
 drivers/iommu/intel/svm.c           |  11 +-
 drivers/iommu/iommu-pages.h         | 154 ++++++++++++++++++++++++++++
 7 files changed, 201 insertions(+), 63 deletions(-)
 create mode 100644 drivers/iommu/iommu-pages.h

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 23cb80d62a9a..ff6045ae8e97 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -32,6 +32,7 @@
 
 #include "iommu.h"
 #include "../irq_remapping.h"
+#include "../iommu-pages.h"
 #include "perf.h"
 #include "trace.h"
 #include "perfmon.h"
@@ -1185,7 +1186,7 @@ static void free_iommu(struct intel_iommu *iommu)
 	}
 
 	if (iommu->qi) {
-		free_page((unsigned long)iommu->qi->desc);
+		iommu_free_page(iommu->qi->desc);
 		kfree(iommu->qi->desc_status);
 		kfree(iommu->qi);
 	}
@@ -1731,7 +1732,8 @@ static void __dmar_enable_qi(struct intel_iommu *iommu)
 int dmar_enable_qi(struct intel_iommu *iommu)
 {
 	struct q_inval *qi;
-	struct page *desc_page;
+	void *desc;
+	int order;
 
 	if (!ecap_qis(iommu->ecap))
 		return -ENOENT;
@@ -1752,19 +1754,19 @@ int dmar_enable_qi(struct intel_iommu *iommu)
 	 * Need two pages to accommodate 256 descriptors of 256 bits each
 	 * if the remapping hardware supports scalable mode translation.
 	 */
-	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
-				     !!ecap_smts(iommu->ecap));
-	if (!desc_page) {
+	order = ecap_smts(iommu->ecap) ? 1 : 0;
+	desc = iommu_alloc_pages_node(iommu->node, GFP_ATOMIC, order);
+	if (!desc) {
 		kfree(qi);
 		iommu->qi = NULL;
 		return -ENOMEM;
 	}
 
-	qi->desc = page_address(desc_page);
+	qi->desc = desc;
 
 	qi->desc_status = kcalloc(QI_LENGTH, sizeof(int), GFP_ATOMIC);
 	if (!qi->desc_status) {
-		free_page((unsigned long) qi->desc);
+		iommu_free_page(qi->desc);
 		kfree(qi);
 		iommu->qi = NULL;
 		return -ENOMEM;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 6fb5f6fceea1..2c676f46e38c 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -28,6 +28,7 @@
 #include "../dma-iommu.h"
 #include "../irq_remapping.h"
 #include "../iommu-sva.h"
+#include "../iommu-pages.h"
 #include "pasid.h"
 #include "cap_audit.h"
 #include "perfmon.h"
@@ -224,22 +225,6 @@ static int __init intel_iommu_setup(char *str)
 }
 __setup("intel_iommu=", intel_iommu_setup);
 
-void *alloc_pgtable_page(int node, gfp_t gfp)
-{
-	struct page *page;
-	void *vaddr = NULL;
-
-	page = alloc_pages_node(node, gfp | __GFP_ZERO, 0);
-	if (page)
-		vaddr = page_address(page);
-	return vaddr;
-}
-
-void free_pgtable_page(void *vaddr)
-{
-	free_page((unsigned long)vaddr);
-}
-
 static int domain_type_is_si(struct dmar_domain *domain)
 {
 	return domain->domain.type == IOMMU_DOMAIN_IDENTITY;
@@ -473,7 +458,7 @@ struct context_entry *iommu_context_addr(struct intel_iommu *iommu, u8 bus,
 		if (!alloc)
 			return NULL;
 
-		context = alloc_pgtable_page(iommu->node, GFP_ATOMIC);
+		context = iommu_alloc_page_node(iommu->node, GFP_ATOMIC);
 		if (!context)
 			return NULL;
 
@@ -647,17 +632,17 @@ static void free_context_table(struct intel_iommu *iommu)
 	for (i = 0; i < ROOT_ENTRY_NR; i++) {
 		context = iommu_context_addr(iommu, i, 0, 0);
 		if (context)
-			free_pgtable_page(context);
+			iommu_free_page(context);
 
 		if (!sm_supported(iommu))
 			continue;
 
 		context = iommu_context_addr(iommu, i, 0x80, 0);
 		if (context)
-			free_pgtable_page(context);
+			iommu_free_page(context);
 	}
 
-	free_pgtable_page(iommu->root_entry);
+	iommu_free_page(iommu->root_entry);
 	iommu->root_entry = NULL;
 }
 
@@ -795,7 +780,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
 		if (!dma_pte_present(pte)) {
 			uint64_t pteval;
 
-			tmp_page = alloc_pgtable_page(domain->nid, gfp);
+			tmp_page = iommu_alloc_page_node(domain->nid, gfp);
 
 			if (!tmp_page)
 				return NULL;
@@ -807,7 +792,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
 
 			if (cmpxchg64(&pte->val, 0ULL, pteval))
 				/* Someone else set it while we were thinking; use theirs. */
-				free_pgtable_page(tmp_page);
+				iommu_free_page(tmp_page);
 			else
 				domain_flush_cache(domain, pte, sizeof(*pte));
 		}
@@ -920,7 +905,7 @@ static void dma_pte_free_level(struct dmar_domain *domain, int level,
 		      last_pfn < level_pfn + level_size(level) - 1)) {
 			dma_clear_pte(pte);
 			domain_flush_cache(domain, pte, sizeof(*pte));
-			free_pgtable_page(level_pte);
+			iommu_free_page(level_pte);
 		}
 next:
 		pfn += level_size(level);
@@ -944,7 +929,7 @@ static void dma_pte_free_pagetable(struct dmar_domain *domain,
 
 	/* free pgd */
 	if (start_pfn == 0 && last_pfn == DOMAIN_MAX_PFN(domain->gaw)) {
-		free_pgtable_page(domain->pgd);
+		iommu_free_page(domain->pgd);
 		domain->pgd = NULL;
 	}
 }
@@ -1046,7 +1031,7 @@ static int iommu_alloc_root_entry(struct intel_iommu *iommu)
 {
 	struct root_entry *root;
 
-	root = alloc_pgtable_page(iommu->node, GFP_ATOMIC);
+	root = iommu_alloc_page_node(iommu->node, GFP_ATOMIC);
 	if (!root) {
 		pr_err("Allocating root entry for %s failed\n",
 			iommu->name);
@@ -1718,7 +1703,7 @@ static void domain_exit(struct dmar_domain *domain)
 		LIST_HEAD(freelist);
 
 		domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw), &freelist);
-		put_pages_list(&freelist);
+		iommu_put_pages_list(&freelist);
 	}
 
 	if (WARN_ON(!list_empty(&domain->devices)))
@@ -2452,7 +2437,7 @@ static int copy_context_table(struct intel_iommu *iommu,
 			if (!old_ce)
 				goto out;
 
-			new_ce = alloc_pgtable_page(iommu->node, GFP_KERNEL);
+			new_ce = iommu_alloc_page_node(iommu->node, GFP_KERNEL);
 			if (!new_ce)
 				goto out_unmap;
 
@@ -3385,7 +3370,7 @@ static int intel_iommu_memory_notifier(struct notifier_block *nb,
 					start_vpfn, mhp->nr_pages,
 					list_empty(&freelist), 0);
 			rcu_read_unlock();
-			put_pages_list(&freelist);
+			iommu_put_pages_list(&freelist);
 		}
 		break;
 	}
@@ -3816,7 +3801,7 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width)
 	domain->max_addr = 0;
 
 	/* always allocate the top pgd */
-	domain->pgd = alloc_pgtable_page(domain->nid, GFP_ATOMIC);
+	domain->pgd = iommu_alloc_page_node(domain->nid, GFP_ATOMIC);
 	if (!domain->pgd)
 		return -ENOMEM;
 	domain_flush_cache(domain, domain->pgd, PAGE_SIZE);
@@ -3960,7 +3945,7 @@ int prepare_domain_attach_device(struct iommu_domain *domain,
 		pte = dmar_domain->pgd;
 		if (dma_pte_present(pte)) {
 			dmar_domain->pgd = phys_to_virt(dma_pte_addr(pte));
-			free_pgtable_page(pte);
+			iommu_free_page(pte);
 		}
 		dmar_domain->agaw--;
 	}
@@ -4107,7 +4092,7 @@ static void intel_iommu_tlb_sync(struct iommu_domain *domain,
 				      start_pfn, nrpages,
 				      list_empty(&gather->freelist), 0);
 
-	put_pages_list(&gather->freelist);
+	iommu_put_pages_list(&gather->freelist);
 }
 
 static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index d02f916d8e59..9fe04cea29c4 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -1069,8 +1069,6 @@ void domain_update_iommu_cap(struct dmar_domain *domain);
 
 int dmar_ir_support(void);
 
-void *alloc_pgtable_page(int node, gfp_t gfp);
-void free_pgtable_page(void *vaddr);
 void iommu_flush_write_buffer(struct intel_iommu *iommu);
 struct iommu_domain *intel_nested_domain_alloc(struct iommu_domain *parent,
 					       const struct iommu_user_data *user_data);
diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c
index 566297bc87dd..39cd9626eb8d 100644
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -22,6 +22,7 @@
 
 #include "iommu.h"
 #include "../irq_remapping.h"
+#include "../iommu-pages.h"
 #include "cap_audit.h"
 
 enum irq_mode {
@@ -527,7 +528,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	struct ir_table *ir_table;
 	struct fwnode_handle *fn;
 	unsigned long *bitmap;
-	struct page *pages;
+	void *ir_table_base;
 
 	if (iommu->ir_table)
 		return 0;
@@ -536,9 +537,9 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	if (!ir_table)
 		return -ENOMEM;
 
-	pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO,
-				 INTR_REMAP_PAGE_ORDER);
-	if (!pages) {
+	ir_table_base = iommu_alloc_pages_node(iommu->node, GFP_KERNEL,
+					       INTR_REMAP_PAGE_ORDER);
+	if (!ir_table_base) {
 		pr_err("IR%d: failed to allocate pages of order %d\n",
 		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
 		goto out_free_table;
@@ -573,7 +574,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	else
 		iommu->ir_domain->msi_parent_ops = &dmar_msi_parent_ops;
 
-	ir_table->base = page_address(pages);
+	ir_table->base = ir_table_base;
 	ir_table->bitmap = bitmap;
 	iommu->ir_table = ir_table;
 
@@ -622,7 +623,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 out_free_bitmap:
 	bitmap_free(bitmap);
 out_free_pages:
-	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
+	iommu_free_pages(ir_table_base, INTR_REMAP_PAGE_ORDER);
 out_free_table:
 	kfree(ir_table);
 
@@ -643,8 +644,7 @@ static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
 			irq_domain_free_fwnode(fn);
 			iommu->ir_domain = NULL;
 		}
-		free_pages((unsigned long)iommu->ir_table->base,
-			   INTR_REMAP_PAGE_ORDER);
+		iommu_free_pages(iommu->ir_table->base, INTR_REMAP_PAGE_ORDER);
 		bitmap_free(iommu->ir_table->bitmap);
 		kfree(iommu->ir_table);
 		iommu->ir_table = NULL;
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index 3239cefa4c33..d46f661dd971 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -20,6 +20,7 @@
 
 #include "iommu.h"
 #include "pasid.h"
+#include "../iommu-pages.h"
 
 /*
  * Intel IOMMU system wide PASID name space:
@@ -38,7 +39,7 @@ int intel_pasid_alloc_table(struct device *dev)
 {
 	struct device_domain_info *info;
 	struct pasid_table *pasid_table;
-	struct page *pages;
+	struct pasid_dir_entry *dir;
 	u32 max_pasid = 0;
 	int order, size;
 
@@ -59,14 +60,13 @@ int intel_pasid_alloc_table(struct device *dev)
 
 	size = max_pasid >> (PASID_PDE_SHIFT - 3);
 	order = size ? get_order(size) : 0;
-	pages = alloc_pages_node(info->iommu->node,
-				 GFP_KERNEL | __GFP_ZERO, order);
-	if (!pages) {
+	dir = iommu_alloc_pages_node(info->iommu->node, GFP_KERNEL, order);
+	if (!dir) {
 		kfree(pasid_table);
 		return -ENOMEM;
 	}
 
-	pasid_table->table = page_address(pages);
+	pasid_table->table = dir;
 	pasid_table->order = order;
 	pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
 	info->pasid_table = pasid_table;
@@ -97,10 +97,10 @@ void intel_pasid_free_table(struct device *dev)
 	max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
 	for (i = 0; i < max_pde; i++) {
 		table = get_pasid_table_from_pde(&dir[i]);
-		free_pgtable_page(table);
+		iommu_free_page(table);
 	}
 
-	free_pages((unsigned long)pasid_table->table, pasid_table->order);
+	iommu_free_pages(pasid_table->table, pasid_table->order);
 	kfree(pasid_table);
 }
 
@@ -146,7 +146,7 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
 retry:
 	entries = get_pasid_table_from_pde(&dir[dir_index]);
 	if (!entries) {
-		entries = alloc_pgtable_page(info->iommu->node, GFP_ATOMIC);
+		entries = iommu_alloc_page_node(info->iommu->node, GFP_ATOMIC);
 		if (!entries)
 			return NULL;
 
@@ -158,7 +158,7 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
 		 */
 		if (cmpxchg64(&dir[dir_index].val, 0ULL,
 			      (u64)virt_to_phys(entries) | PASID_PTE_PRESENT)) {
-			free_pgtable_page(entries);
+			iommu_free_page(entries);
 			goto retry;
 		}
 		if (!ecap_coherent(info->iommu->ecap)) {
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 40edd282903f..a691f917456c 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -23,6 +23,7 @@
 #include "pasid.h"
 #include "perf.h"
 #include "../iommu-sva.h"
+#include "../iommu-pages.h"
 #include "trace.h"
 
 static irqreturn_t prq_event_thread(int irq, void *d);
@@ -64,16 +65,14 @@ svm_lookup_device_by_dev(struct intel_svm *svm, struct device *dev)
 int intel_svm_enable_prq(struct intel_iommu *iommu)
 {
 	struct iopf_queue *iopfq;
-	struct page *pages;
 	int irq, ret;
 
-	pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, PRQ_ORDER);
-	if (!pages) {
+	iommu->prq = iommu_alloc_pages(GFP_KERNEL, PRQ_ORDER);
+	if (!iommu->prq) {
 		pr_warn("IOMMU: %s: Failed to allocate page request queue\n",
 			iommu->name);
 		return -ENOMEM;
 	}
-	iommu->prq = page_address(pages);
 
 	irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PRQ + iommu->seq_id, iommu->node, iommu);
 	if (irq <= 0) {
@@ -118,7 +117,7 @@ int intel_svm_enable_prq(struct intel_iommu *iommu)
 	dmar_free_hwirq(irq);
 	iommu->pr_irq = 0;
 free_prq:
-	free_pages((unsigned long)iommu->prq, PRQ_ORDER);
+	iommu_free_pages(iommu->prq, PRQ_ORDER);
 	iommu->prq = NULL;
 
 	return ret;
@@ -141,7 +140,7 @@ int intel_svm_finish_prq(struct intel_iommu *iommu)
 		iommu->iopf_queue = NULL;
 	}
 
-	free_pages((unsigned long)iommu->prq, PRQ_ORDER);
+	iommu_free_pages(iommu->prq, PRQ_ORDER);
 	iommu->prq = NULL;
 
 	return 0;
diff --git a/drivers/iommu/iommu-pages.h b/drivers/iommu/iommu-pages.h
new file mode 100644
index 000000000000..35bfa369b134
--- /dev/null
+++ b/drivers/iommu/iommu-pages.h
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2024, Google LLC.
+ * Pasha Tatashin <pasha.tatashin@soleen.com>
+ */
+
+#ifndef __IOMMU_PAGES_H
+#define __IOMMU_PAGES_H
+
+#include <linux/vmstat.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+
+/*
+ * All page allocations that should be reported to as "iommu-pagetables" to
+ * userspace must use on of the functions below.  This includes allocations of
+ * page-tables and other per-iommu_domain configuration structures.
+ *
+ * This is necessary for the proper accounting as IOMMU state can be rather
+ * large, i.e. multiple gigabytes in size.
+ */
+
+/**
+ * __iommu_alloc_pages - allocate a zeroed page of a given order.
+ * @gfp: buddy allocator flags
+ * @order: page order
+ *
+ * returns the head struct page of the allocated page.
+ */
+static inline struct page *__iommu_alloc_pages(gfp_t gfp, int order)
+{
+	struct page *page;
+
+	page = alloc_pages(gfp | __GFP_ZERO, order);
+	if (unlikely(!page))
+		return NULL;
+
+	return page;
+}
+
+/**
+ * __iommu_free_pages - free page of a given order
+ * @page: head struct page of the page
+ * @order: page order
+ */
+static inline void __iommu_free_pages(struct page *page, int order)
+{
+	if (!page)
+		return;
+
+	__free_pages(page, order);
+}
+
+/**
+ * iommu_alloc_pages_node - allocate a zeroed page of a given order from
+ * specific NUMA node.
+ * @nid: memory NUMA node id
+ * @gfp: buddy allocator flags
+ * @order: page order
+ *
+ * returns the virtual address of the allocated page
+ */
+static inline void *iommu_alloc_pages_node(int nid, gfp_t gfp, int order)
+{
+	struct page *page = alloc_pages_node(nid, gfp | __GFP_ZERO, order);
+
+	if (unlikely(!page))
+		return NULL;
+
+	return page_address(page);
+}
+
+/**
+ * iommu_alloc_pages - allocate a zeroed page of a given order
+ * @gfp: buddy allocator flags
+ * @order: page order
+ *
+ * returns the virtual address of the allocated page
+ */
+static inline void *iommu_alloc_pages(gfp_t gfp, int order)
+{
+	struct page *page = __iommu_alloc_pages(gfp, order);
+
+	if (unlikely(!page))
+		return NULL;
+
+	return page_address(page);
+}
+
+/**
+ * iommu_alloc_page_node - allocate a zeroed page at specific NUMA node.
+ * @nid: memory NUMA node id
+ * @gfp: buddy allocator flags
+ *
+ * returns the virtual address of the allocated page
+ */
+static inline void *iommu_alloc_page_node(int nid, gfp_t gfp)
+{
+	return iommu_alloc_pages_node(nid, gfp, 0);
+}
+
+/**
+ * iommu_alloc_page - allocate a zeroed page
+ * @gfp: buddy allocator flags
+ *
+ * returns the virtual address of the allocated page
+ */
+static inline void *iommu_alloc_page(gfp_t gfp)
+{
+	return iommu_alloc_pages(gfp, 0);
+}
+
+/**
+ * iommu_free_pages - free page of a given order
+ * @virt: virtual address of the page to be freed.
+ * @order: page order
+ */
+static inline void iommu_free_pages(void *virt, int order)
+{
+	if (!virt)
+		return;
+
+	__iommu_free_pages(virt_to_page(virt), order);
+}
+
+/**
+ * iommu_free_page - free page
+ * @virt: virtual address of the page to be freed.
+ */
+static inline void iommu_free_page(void *virt)
+{
+	iommu_free_pages(virt, 0);
+}
+
+/**
+ * iommu_put_pages_list - free a list of pages.
+ * @page: the head of the lru list to be freed.
+ *
+ * There are no locking requirement for these pages, as they are going to be
+ * put on a free list as soon as refcount reaches 0. Pages are put on this LRU
+ * list once they are removed from the IOMMU page tables. However, they can
+ * still be access through debugfs.
+ */
+static inline void iommu_put_pages_list(struct list_head *page)
+{
+	while (!list_empty(page)) {
+		struct page *p = list_entry(page->prev, struct page, lru);
+
+		list_del(&p->lru);
+		put_page(p);
+	}
+}
+
+#endif	/* __IOMMU_PAGES_H */
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 02/11] iommu/dma: use iommu_put_pages_list() to releae freelist

[Pasha Tatashin]

Free the IOMMU page tables via iommu_put_pages_list(). The page tables
were allocated via iommu_alloc_* functions in architecture specific
places, but are released in dma-iommu if the freelist is gathered during
map/unmap operations into iommu_iotlb_gather data structure.

Currently, only iommu/intel that does that.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
---
 drivers/iommu/dma-iommu.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 50ccc4f1ef81..fa0c4be79f9f 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -32,6 +32,7 @@
 #include <trace/events/swiotlb.h>
 
 #include "dma-iommu.h"
+#include "iommu-pages.h"
 
 struct iommu_dma_msi_page {
 	struct list_head	list;
@@ -156,7 +157,7 @@ static void fq_ring_free_locked(struct iommu_dma_cookie *cookie, struct iova_fq
 		if (fq->entries[idx].counter >= counter)
 			break;
 
-		put_pages_list(&fq->entries[idx].freelist);
+		iommu_put_pages_list(&fq->entries[idx].freelist);
 		free_iova_fast(&cookie->iovad,
 			       fq->entries[idx].iova_pfn,
 			       fq->entries[idx].pages);
@@ -254,7 +255,7 @@ static void iommu_dma_free_fq_single(struct iova_fq *fq)
 	int idx;
 
 	fq_ring_for_each(idx, fq)
-		put_pages_list(&fq->entries[idx].freelist);
+		iommu_put_pages_list(&fq->entries[idx].freelist);
 	vfree(fq);
 }
 
@@ -267,7 +268,7 @@ static void iommu_dma_free_fq_percpu(struct iova_fq __percpu *percpu_fq)
 		struct iova_fq *fq = per_cpu_ptr(percpu_fq, cpu);
 
 		fq_ring_for_each(idx, fq)
-			put_pages_list(&fq->entries[idx].freelist);
+			iommu_put_pages_list(&fq->entries[idx].freelist);
 	}
 
 	free_percpu(percpu_fq);
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 03/11] iommu/amd: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/amd/* files to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/amd/amd_iommu.h     |  8 ---
 drivers/iommu/amd/init.c          | 91 ++++++++++++++-----------------
 drivers/iommu/amd/io_pgtable.c    | 13 +++--
 drivers/iommu/amd/io_pgtable_v2.c | 20 +++----
 drivers/iommu/amd/iommu.c         | 13 +++--
 5 files changed, 64 insertions(+), 81 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
index 8b3601f285fd..9270c820a2ab 100644
--- a/drivers/iommu/amd/amd_iommu.h
+++ b/drivers/iommu/amd/amd_iommu.h
@@ -142,14 +142,6 @@ static inline int get_pci_sbdf_id(struct pci_dev *pdev)
 	return PCI_SEG_DEVID_TO_SBDF(seg, devid);
 }
 
-static inline void *alloc_pgtable_page(int nid, gfp_t gfp)
-{
-	struct page *page;
-
-	page = alloc_pages_node(nid, gfp | __GFP_ZERO, 0);
-	return page ? page_address(page) : NULL;
-}
-
 bool translation_pre_enabled(struct amd_iommu *iommu);
 bool amd_iommu_is_attach_deferred(struct device *dev);
 int __init add_special_device(u8 type, u8 id, u32 *devid, bool cmd_line);
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index c83bd0c2a1c9..239ddf46426f 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -35,6 +35,7 @@
 
 #include "amd_iommu.h"
 #include "../irq_remapping.h"
+#include "../iommu-pages.h"
 
 /*
  * definitions for the ACPI scanning code
@@ -648,8 +649,8 @@ static int __init find_last_devid_acpi(struct acpi_table_header *table, u16 pci_
 /* Allocate per PCI segment device table */
 static inline int __init alloc_dev_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	pci_seg->dev_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO | GFP_DMA32,
-						      get_order(pci_seg->dev_table_size));
+	pci_seg->dev_table = iommu_alloc_pages(GFP_KERNEL | GFP_DMA32,
+					       get_order(pci_seg->dev_table_size));
 	if (!pci_seg->dev_table)
 		return -ENOMEM;
 
@@ -658,17 +659,16 @@ static inline int __init alloc_dev_table(struct amd_iommu_pci_seg *pci_seg)
 
 static inline void free_dev_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	free_pages((unsigned long)pci_seg->dev_table,
-		    get_order(pci_seg->dev_table_size));
+	iommu_free_pages(pci_seg->dev_table,
+			 get_order(pci_seg->dev_table_size));
 	pci_seg->dev_table = NULL;
 }
 
 /* Allocate per PCI segment IOMMU rlookup table. */
 static inline int __init alloc_rlookup_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	pci_seg->rlookup_table = (void *)__get_free_pages(
-						GFP_KERNEL | __GFP_ZERO,
-						get_order(pci_seg->rlookup_table_size));
+	pci_seg->rlookup_table = iommu_alloc_pages(GFP_KERNEL,
+						   get_order(pci_seg->rlookup_table_size));
 	if (pci_seg->rlookup_table == NULL)
 		return -ENOMEM;
 
@@ -677,16 +677,15 @@ static inline int __init alloc_rlookup_table(struct amd_iommu_pci_seg *pci_seg)
 
 static inline void free_rlookup_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	free_pages((unsigned long)pci_seg->rlookup_table,
-		   get_order(pci_seg->rlookup_table_size));
+	iommu_free_pages(pci_seg->rlookup_table,
+			 get_order(pci_seg->rlookup_table_size));
 	pci_seg->rlookup_table = NULL;
 }
 
 static inline int __init alloc_irq_lookup_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	pci_seg->irq_lookup_table = (void *)__get_free_pages(
-					     GFP_KERNEL | __GFP_ZERO,
-					     get_order(pci_seg->rlookup_table_size));
+	pci_seg->irq_lookup_table = iommu_alloc_pages(GFP_KERNEL,
+						      get_order(pci_seg->rlookup_table_size));
 	kmemleak_alloc(pci_seg->irq_lookup_table,
 		       pci_seg->rlookup_table_size, 1, GFP_KERNEL);
 	if (pci_seg->irq_lookup_table == NULL)
@@ -698,8 +697,8 @@ static inline int __init alloc_irq_lookup_table(struct amd_iommu_pci_seg *pci_se
 static inline void free_irq_lookup_table(struct amd_iommu_pci_seg *pci_seg)
 {
 	kmemleak_free(pci_seg->irq_lookup_table);
-	free_pages((unsigned long)pci_seg->irq_lookup_table,
-		   get_order(pci_seg->rlookup_table_size));
+	iommu_free_pages(pci_seg->irq_lookup_table,
+			 get_order(pci_seg->rlookup_table_size));
 	pci_seg->irq_lookup_table = NULL;
 }
 
@@ -707,8 +706,8 @@ static int __init alloc_alias_table(struct amd_iommu_pci_seg *pci_seg)
 {
 	int i;
 
-	pci_seg->alias_table = (void *)__get_free_pages(GFP_KERNEL,
-					get_order(pci_seg->alias_table_size));
+	pci_seg->alias_table = iommu_alloc_pages(GFP_KERNEL,
+						 get_order(pci_seg->alias_table_size));
 	if (!pci_seg->alias_table)
 		return -ENOMEM;
 
@@ -723,8 +722,8 @@ static int __init alloc_alias_table(struct amd_iommu_pci_seg *pci_seg)
 
 static void __init free_alias_table(struct amd_iommu_pci_seg *pci_seg)
 {
-	free_pages((unsigned long)pci_seg->alias_table,
-		   get_order(pci_seg->alias_table_size));
+	iommu_free_pages(pci_seg->alias_table,
+			 get_order(pci_seg->alias_table_size));
 	pci_seg->alias_table = NULL;
 }
 
@@ -735,8 +734,8 @@ static void __init free_alias_table(struct amd_iommu_pci_seg *pci_seg)
  */
 static int __init alloc_command_buffer(struct amd_iommu *iommu)
 {
-	iommu->cmd_buf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
-						  get_order(CMD_BUFFER_SIZE));
+	iommu->cmd_buf = iommu_alloc_pages(GFP_KERNEL,
+					   get_order(CMD_BUFFER_SIZE));
 
 	return iommu->cmd_buf ? 0 : -ENOMEM;
 }
@@ -844,19 +843,19 @@ static void iommu_disable_command_buffer(struct amd_iommu *iommu)
 
 static void __init free_command_buffer(struct amd_iommu *iommu)
 {
-	free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE));
+	iommu_free_pages(iommu->cmd_buf, get_order(CMD_BUFFER_SIZE));
 }
 
 static void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu,
 					 gfp_t gfp, size_t size)
 {
 	int order = get_order(size);
-	void *buf = (void *)__get_free_pages(gfp, order);
+	void *buf = iommu_alloc_pages(gfp, order);
 
 	if (buf &&
 	    check_feature(FEATURE_SNP) &&
 	    set_memory_4k((unsigned long)buf, (1 << order))) {
-		free_pages((unsigned long)buf, order);
+		iommu_free_pages(buf, order);
 		buf = NULL;
 	}
 
@@ -866,7 +865,7 @@ static void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu,
 /* allocates the memory where the IOMMU will log its events to */
 static int __init alloc_event_buffer(struct amd_iommu *iommu)
 {
-	iommu->evt_buf = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO,
+	iommu->evt_buf = iommu_alloc_4k_pages(iommu, GFP_KERNEL,
 					      EVT_BUFFER_SIZE);
 
 	return iommu->evt_buf ? 0 : -ENOMEM;
@@ -900,14 +899,13 @@ static void iommu_disable_event_buffer(struct amd_iommu *iommu)
 
 static void __init free_event_buffer(struct amd_iommu *iommu)
 {
-	free_pages((unsigned long)iommu->evt_buf, get_order(EVT_BUFFER_SIZE));
+	iommu_free_pages(iommu->evt_buf, get_order(EVT_BUFFER_SIZE));
 }
 
 /* allocates the memory where the IOMMU will log its events to */
 static int __init alloc_ppr_log(struct amd_iommu *iommu)
 {
-	iommu->ppr_log = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO,
-					      PPR_LOG_SIZE);
+	iommu->ppr_log = iommu_alloc_4k_pages(iommu, GFP_KERNEL, PPR_LOG_SIZE);
 
 	return iommu->ppr_log ? 0 : -ENOMEM;
 }
@@ -936,14 +934,14 @@ static void iommu_enable_ppr_log(struct amd_iommu *iommu)
 
 static void __init free_ppr_log(struct amd_iommu *iommu)
 {
-	free_pages((unsigned long)iommu->ppr_log, get_order(PPR_LOG_SIZE));
+	iommu_free_pages(iommu->ppr_log, get_order(PPR_LOG_SIZE));
 }
 
 static void free_ga_log(struct amd_iommu *iommu)
 {
 #ifdef CONFIG_IRQ_REMAP
-	free_pages((unsigned long)iommu->ga_log, get_order(GA_LOG_SIZE));
-	free_pages((unsigned long)iommu->ga_log_tail, get_order(8));
+	iommu_free_pages(iommu->ga_log, get_order(GA_LOG_SIZE));
+	iommu_free_pages(iommu->ga_log_tail, get_order(8));
 #endif
 }
 
@@ -988,13 +986,11 @@ static int iommu_init_ga_log(struct amd_iommu *iommu)
 	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
 		return 0;
 
-	iommu->ga_log = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
-					get_order(GA_LOG_SIZE));
+	iommu->ga_log = iommu_alloc_pages(GFP_KERNEL, get_order(GA_LOG_SIZE));
 	if (!iommu->ga_log)
 		goto err_out;
 
-	iommu->ga_log_tail = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
-					get_order(8));
+	iommu->ga_log_tail = iommu_alloc_pages(GFP_KERNEL, get_order(8));
 	if (!iommu->ga_log_tail)
 		goto err_out;
 
@@ -1007,7 +1003,7 @@ static int iommu_init_ga_log(struct amd_iommu *iommu)
 
 static int __init alloc_cwwb_sem(struct amd_iommu *iommu)
 {
-	iommu->cmd_sem = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, 1);
+	iommu->cmd_sem = iommu_alloc_4k_pages(iommu, GFP_KERNEL, 1);
 
 	return iommu->cmd_sem ? 0 : -ENOMEM;
 }
@@ -1015,7 +1011,7 @@ static int __init alloc_cwwb_sem(struct amd_iommu *iommu)
 static void __init free_cwwb_sem(struct amd_iommu *iommu)
 {
 	if (iommu->cmd_sem)
-		free_page((unsigned long)iommu->cmd_sem);
+		iommu_free_page((void *)iommu->cmd_sem);
 }
 
 static void iommu_enable_xt(struct amd_iommu *iommu)
@@ -1080,7 +1076,6 @@ static bool __copy_device_table(struct amd_iommu *iommu)
 	u32 lo, hi, devid, old_devtb_size;
 	phys_addr_t old_devtb_phys;
 	u16 dom_id, dte_v, irq_v;
-	gfp_t gfp_flag;
 	u64 tmp;
 
 	/* Each IOMMU use separate device table with the same size */
@@ -1114,9 +1109,8 @@ static bool __copy_device_table(struct amd_iommu *iommu)
 	if (!old_devtb)
 		return false;
 
-	gfp_flag = GFP_KERNEL | __GFP_ZERO | GFP_DMA32;
-	pci_seg->old_dev_tbl_cpy = (void *)__get_free_pages(gfp_flag,
-						    get_order(pci_seg->dev_table_size));
+	pci_seg->old_dev_tbl_cpy = iommu_alloc_pages(GFP_KERNEL | GFP_DMA32,
+						     get_order(pci_seg->dev_table_size));
 	if (pci_seg->old_dev_tbl_cpy == NULL) {
 		pr_err("Failed to allocate memory for copying old device table!\n");
 		memunmap(old_devtb);
@@ -2800,8 +2794,8 @@ static void early_enable_iommus(void)
 
 		for_each_pci_segment(pci_seg) {
 			if (pci_seg->old_dev_tbl_cpy != NULL) {
-				free_pages((unsigned long)pci_seg->old_dev_tbl_cpy,
-						get_order(pci_seg->dev_table_size));
+				iommu_free_pages(pci_seg->old_dev_tbl_cpy,
+						 get_order(pci_seg->dev_table_size));
 				pci_seg->old_dev_tbl_cpy = NULL;
 			}
 		}
@@ -2814,8 +2808,8 @@ static void early_enable_iommus(void)
 		pr_info("Copied DEV table from previous kernel.\n");
 
 		for_each_pci_segment(pci_seg) {
-			free_pages((unsigned long)pci_seg->dev_table,
-				   get_order(pci_seg->dev_table_size));
+			iommu_free_pages(pci_seg->dev_table,
+					 get_order(pci_seg->dev_table_size));
 			pci_seg->dev_table = pci_seg->old_dev_tbl_cpy;
 		}
 
@@ -3018,8 +3012,8 @@ static bool __init check_ioapic_information(void)
 
 static void __init free_dma_resources(void)
 {
-	free_pages((unsigned long)amd_iommu_pd_alloc_bitmap,
-		   get_order(MAX_DOMAIN_ID/8));
+	iommu_free_pages(amd_iommu_pd_alloc_bitmap,
+			 get_order(MAX_DOMAIN_ID / 8));
 	amd_iommu_pd_alloc_bitmap = NULL;
 
 	free_unity_maps();
@@ -3091,9 +3085,8 @@ static int __init early_amd_iommu_init(void)
 	/* Device table - directly used by all IOMMUs */
 	ret = -ENOMEM;
 
-	amd_iommu_pd_alloc_bitmap = (void *)__get_free_pages(
-					    GFP_KERNEL | __GFP_ZERO,
-					    get_order(MAX_DOMAIN_ID/8));
+	amd_iommu_pd_alloc_bitmap = iommu_alloc_pages(GFP_KERNEL,
+						      get_order(MAX_DOMAIN_ID / 8));
 	if (amd_iommu_pd_alloc_bitmap == NULL)
 		goto out;
 
diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
index 2a0d1e97e52f..9d9a7fde59e7 100644
--- a/drivers/iommu/amd/io_pgtable.c
+++ b/drivers/iommu/amd/io_pgtable.c
@@ -22,6 +22,7 @@
 
 #include "amd_iommu_types.h"
 #include "amd_iommu.h"
+#include "../iommu-pages.h"
 
 static void v1_tlb_flush_all(void *cookie)
 {
@@ -156,7 +157,7 @@ static bool increase_address_space(struct protection_domain *domain,
 	bool ret = true;
 	u64 *pte;
 
-	pte = alloc_pgtable_page(domain->nid, gfp);
+	pte = iommu_alloc_page_node(domain->nid, gfp);
 	if (!pte)
 		return false;
 
@@ -187,7 +188,7 @@ static bool increase_address_space(struct protection_domain *domain,
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
-	free_page((unsigned long)pte);
+	iommu_free_page(pte);
 
 	return ret;
 }
@@ -250,7 +251,7 @@ static u64 *alloc_pte(struct protection_domain *domain,
 
 		if (!IOMMU_PTE_PRESENT(__pte) ||
 		    pte_level == PAGE_MODE_NONE) {
-			page = alloc_pgtable_page(domain->nid, gfp);
+			page = iommu_alloc_page_node(domain->nid, gfp);
 
 			if (!page)
 				return NULL;
@@ -259,7 +260,7 @@ static u64 *alloc_pte(struct protection_domain *domain,
 
 			/* pte could have been changed somewhere. */
 			if (!try_cmpxchg64(pte, &__pte, __npte))
-				free_page((unsigned long)page);
+				iommu_free_page(page);
 			else if (IOMMU_PTE_PRESENT(__pte))
 				*updated = true;
 
@@ -431,7 +432,7 @@ static int iommu_v1_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
 	}
 
 	/* Everything flushed out, free pages now */
-	put_pages_list(&freelist);
+	iommu_put_pages_list(&freelist);
 
 	return ret;
 }
@@ -580,7 +581,7 @@ static void v1_free_pgtable(struct io_pgtable *iop)
 	/* Make changes visible to IOMMUs */
 	amd_iommu_domain_update(dom);
 
-	put_pages_list(&freelist);
+	iommu_put_pages_list(&freelist);
 }
 
 static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
diff --git a/drivers/iommu/amd/io_pgtable_v2.c b/drivers/iommu/amd/io_pgtable_v2.c
index 6d69ba60744f..477371b1ed54 100644
--- a/drivers/iommu/amd/io_pgtable_v2.c
+++ b/drivers/iommu/amd/io_pgtable_v2.c
@@ -18,6 +18,7 @@
 
 #include "amd_iommu_types.h"
 #include "amd_iommu.h"
+#include "../iommu-pages.h"
 
 #define IOMMU_PAGE_PRESENT	BIT_ULL(0)	/* Is present */
 #define IOMMU_PAGE_RW		BIT_ULL(1)	/* Writeable */
@@ -99,11 +100,6 @@ static inline int page_size_to_level(u64 pg_size)
 	return PAGE_MODE_1_LEVEL;
 }
 
-static inline void free_pgtable_page(u64 *pt)
-{
-	free_page((unsigned long)pt);
-}
-
 static void free_pgtable(u64 *pt, int level)
 {
 	u64 *p;
@@ -125,10 +121,10 @@ static void free_pgtable(u64 *pt, int level)
 		if (level > 2)
 			free_pgtable(p, level - 1);
 		else
-			free_pgtable_page(p);
+			iommu_free_page(p);
 	}
 
-	free_pgtable_page(pt);
+	iommu_free_page(pt);
 }
 
 /* Allocate page table */
@@ -156,14 +152,14 @@ static u64 *v2_alloc_pte(int nid, u64 *pgd, unsigned long iova,
 		}
 
 		if (!IOMMU_PTE_PRESENT(__pte)) {
-			page = alloc_pgtable_page(nid, gfp);
+			page = iommu_alloc_page_node(nid, gfp);
 			if (!page)
 				return NULL;
 
 			__npte = set_pgtable_attr(page);
 			/* pte could have been changed somewhere. */
 			if (cmpxchg64(pte, __pte, __npte) != __pte)
-				free_pgtable_page(page);
+				iommu_free_page(page);
 			else if (IOMMU_PTE_PRESENT(__pte))
 				*updated = true;
 
@@ -185,7 +181,7 @@ static u64 *v2_alloc_pte(int nid, u64 *pgd, unsigned long iova,
 		if (pg_size == IOMMU_PAGE_SIZE_1G)
 			free_pgtable(__pte, end_level - 1);
 		else if (pg_size == IOMMU_PAGE_SIZE_2M)
-			free_pgtable_page(__pte);
+			iommu_free_page(__pte);
 	}
 
 	return pte;
@@ -374,7 +370,7 @@ static struct io_pgtable *v2_alloc_pgtable(struct io_pgtable_cfg *cfg, void *coo
 	int ret;
 	int ias = IOMMU_IN_ADDR_BIT_SIZE;
 
-	pgtable->pgd = alloc_pgtable_page(pdom->nid, GFP_ATOMIC);
+	pgtable->pgd = iommu_alloc_page_node(pdom->nid, GFP_ATOMIC);
 	if (!pgtable->pgd)
 		return NULL;
 
@@ -397,7 +393,7 @@ static struct io_pgtable *v2_alloc_pgtable(struct io_pgtable_cfg *cfg, void *coo
 	return &pgtable->iop;
 
 err_free_pgd:
-	free_pgtable_page(pgtable->pgd);
+	iommu_free_page(pgtable->pgd);
 
 	return NULL;
 }
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 4283dd8191f0..0c7bd09ab617 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -42,6 +42,7 @@
 #include "amd_iommu.h"
 #include "../dma-iommu.h"
 #include "../irq_remapping.h"
+#include "../iommu-pages.h"
 
 #define CMD_SET_TYPE(cmd, t) ((cmd)->data[1] |= ((t) << 28))
 
@@ -1637,7 +1638,7 @@ static void free_gcr3_tbl_level1(u64 *tbl)
 
 		ptr = iommu_phys_to_virt(tbl[i] & PAGE_MASK);
 
-		free_page((unsigned long)ptr);
+		iommu_free_page(ptr);
 	}
 }
 
@@ -1665,7 +1666,7 @@ static void free_gcr3_table(struct protection_domain *domain)
 	else
 		BUG_ON(domain->glx != 0);
 
-	free_page((unsigned long)domain->gcr3_tbl);
+	iommu_free_page(domain->gcr3_tbl);
 }
 
 /*
@@ -1692,7 +1693,7 @@ static int setup_gcr3_table(struct protection_domain *domain, int pasids)
 	if (levels > amd_iommu_max_glx_val)
 		return -EINVAL;
 
-	domain->gcr3_tbl = alloc_pgtable_page(domain->nid, GFP_ATOMIC);
+	domain->gcr3_tbl = iommu_alloc_page_node(domain->nid, GFP_ATOMIC);
 	if (domain->gcr3_tbl == NULL)
 		return -ENOMEM;
 
@@ -2074,7 +2075,7 @@ static void protection_domain_free(struct protection_domain *domain)
 		free_gcr3_table(domain);
 
 	if (domain->iop.root)
-		free_page((unsigned long)domain->iop.root);
+		iommu_free_page(domain->iop.root);
 
 	if (domain->id)
 		domain_id_free(domain->id);
@@ -2089,7 +2090,7 @@ static int protection_domain_init_v1(struct protection_domain *domain, int mode)
 	BUG_ON(mode < PAGE_MODE_NONE || mode > PAGE_MODE_6_LEVEL);
 
 	if (mode != PAGE_MODE_NONE) {
-		pt_root = (void *)get_zeroed_page(GFP_KERNEL);
+		pt_root = iommu_alloc_page(GFP_KERNEL);
 		if (!pt_root)
 			return -ENOMEM;
 	}
@@ -2762,7 +2763,7 @@ static u64 *__get_gcr3_pte(u64 *root, int level, u32 pasid, bool alloc)
 			if (!alloc)
 				return NULL;
 
-			root = (void *)get_zeroed_page(GFP_ATOMIC);
+			root = iommu_alloc_page(GFP_ATOMIC);
 			if (root == NULL)
 				return NULL;
 
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 04/11] iommu/io-pgtable-arm: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/io-pgtable-arm.c to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/io-pgtable-arm.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index f7828a7aad41..3d23b924cec1 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -21,6 +21,7 @@
 #include <asm/barrier.h>
 
 #include "io-pgtable-arm.h"
+#include "iommu-pages.h"
 
 #define ARM_LPAE_MAX_ADDR_BITS		52
 #define ARM_LPAE_S2_MAX_CONCAT_PAGES	16
@@ -198,14 +199,10 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
 
 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
 
-	if (cfg->alloc) {
+	if (cfg->alloc)
 		pages = cfg->alloc(cookie, size, gfp);
-	} else {
-		struct page *p;
-
-		p = alloc_pages_node(dev_to_node(dev), gfp | __GFP_ZERO, order);
-		pages = p ? page_address(p) : NULL;
-	}
+	else
+		pages = iommu_alloc_pages_node(dev_to_node(dev), gfp, order);
 
 	if (!pages)
 		return NULL;
@@ -233,7 +230,7 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
 	if (cfg->free)
 		cfg->free(cookie, pages, size);
 	else
-		free_pages((unsigned long)pages, order);
+		iommu_free_pages(pages, order);
 
 	return NULL;
 }
@@ -249,7 +246,7 @@ static void __arm_lpae_free_pages(void *pages, size_t size,
 	if (cfg->free)
 		cfg->free(cookie, pages, size);
 	else
-		free_pages((unsigned long)pages, get_order(size));
+		iommu_free_pages(pages, get_order(size));
 }
 
 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 05/11] iommu/io-pgtable-dart: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/io-pgtable-dart.c to use the new page allocation functions
provided in iommu-pages.h., and remove unnecessary struct io_pgtable_cfg
argument from __dart_alloc_pages().

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Janne Grunau <j@jannau.net>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/io-pgtable-dart.c | 37 +++++++++++++--------------------
 1 file changed, 14 insertions(+), 23 deletions(-)

diff --git a/drivers/iommu/io-pgtable-dart.c b/drivers/iommu/io-pgtable-dart.c
index 74b1ef2b96be..ad28031e1e93 100644
--- a/drivers/iommu/io-pgtable-dart.c
+++ b/drivers/iommu/io-pgtable-dart.c
@@ -23,6 +23,7 @@
 #include <linux/types.h>
 
 #include <asm/barrier.h>
+#include "iommu-pages.h"
 
 #define DART1_MAX_ADDR_BITS	36
 
@@ -106,18 +107,12 @@ static phys_addr_t iopte_to_paddr(dart_iopte pte,
 	return paddr;
 }
 
-static void *__dart_alloc_pages(size_t size, gfp_t gfp,
-				    struct io_pgtable_cfg *cfg)
+static void *__dart_alloc_pages(size_t size, gfp_t gfp)
 {
 	int order = get_order(size);
-	struct page *p;
 
 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
-	p = alloc_pages(gfp | __GFP_ZERO, order);
-	if (!p)
-		return NULL;
-
-	return page_address(p);
+	return iommu_alloc_pages(gfp, order);
 }
 
 static int dart_init_pte(struct dart_io_pgtable *data,
@@ -262,13 +257,13 @@ static int dart_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
 
 	/* no L2 table present */
 	if (!pte) {
-		cptep = __dart_alloc_pages(tblsz, gfp, cfg);
+		cptep = __dart_alloc_pages(tblsz, gfp);
 		if (!cptep)
 			return -ENOMEM;
 
 		pte = dart_install_table(cptep, ptep, 0, data);
 		if (pte)
-			free_pages((unsigned long)cptep, get_order(tblsz));
+			iommu_free_pages(cptep, get_order(tblsz));
 
 		/* L2 table is present (now) */
 		pte = READ_ONCE(*ptep);
@@ -419,8 +414,7 @@ apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
 	cfg->apple_dart_cfg.n_ttbrs = 1 << data->tbl_bits;
 
 	for (i = 0; i < cfg->apple_dart_cfg.n_ttbrs; ++i) {
-		data->pgd[i] = __dart_alloc_pages(DART_GRANULE(data), GFP_KERNEL,
-					   cfg);
+		data->pgd[i] = __dart_alloc_pages(DART_GRANULE(data), GFP_KERNEL);
 		if (!data->pgd[i])
 			goto out_free_data;
 		cfg->apple_dart_cfg.ttbr[i] = virt_to_phys(data->pgd[i]);
@@ -429,9 +423,10 @@ apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
 	return &data->iop;
 
 out_free_data:
-	while (--i >= 0)
-		free_pages((unsigned long)data->pgd[i],
-			   get_order(DART_GRANULE(data)));
+	while (--i >= 0) {
+		iommu_free_pages(data->pgd[i],
+				 get_order(DART_GRANULE(data)));
+	}
 	kfree(data);
 	return NULL;
 }
@@ -439,6 +434,7 @@ apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
 static void apple_dart_free_pgtable(struct io_pgtable *iop)
 {
 	struct dart_io_pgtable *data = io_pgtable_to_data(iop);
+	int order = get_order(DART_GRANULE(data));
 	dart_iopte *ptep, *end;
 	int i;
 
@@ -449,15 +445,10 @@ static void apple_dart_free_pgtable(struct io_pgtable *iop)
 		while (ptep != end) {
 			dart_iopte pte = *ptep++;
 
-			if (pte) {
-				unsigned long page =
-					(unsigned long)iopte_deref(pte, data);
-
-				free_pages(page, get_order(DART_GRANULE(data)));
-			}
+			if (pte)
+				iommu_free_pages(iopte_deref(pte, data), order);
 		}
-		free_pages((unsigned long)data->pgd[i],
-			   get_order(DART_GRANULE(data)));
+		iommu_free_pages(data->pgd[i], order);
 	}
 
 	kfree(data);
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 06/11] iommu/exynos: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/exynos-iommu.c to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/exynos-iommu.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 2c6e9094f1e9..3eab0ae65a4f 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -22,6 +22,8 @@
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
 
+#include "iommu-pages.h"
+
 typedef u32 sysmmu_iova_t;
 typedef u32 sysmmu_pte_t;
 static struct iommu_domain exynos_identity_domain;
@@ -900,11 +902,11 @@ static struct iommu_domain *exynos_iommu_domain_alloc_paging(struct device *dev)
 	if (!domain)
 		return NULL;
 
-	domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
+	domain->pgtable = iommu_alloc_pages(GFP_KERNEL, 2);
 	if (!domain->pgtable)
 		goto err_pgtable;
 
-	domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
+	domain->lv2entcnt = iommu_alloc_pages(GFP_KERNEL, 1);
 	if (!domain->lv2entcnt)
 		goto err_counter;
 
@@ -930,9 +932,9 @@ static struct iommu_domain *exynos_iommu_domain_alloc_paging(struct device *dev)
 	return &domain->domain;
 
 err_lv2ent:
-	free_pages((unsigned long)domain->lv2entcnt, 1);
+	iommu_free_pages(domain->lv2entcnt, 1);
 err_counter:
-	free_pages((unsigned long)domain->pgtable, 2);
+	iommu_free_pages(domain->pgtable, 2);
 err_pgtable:
 	kfree(domain);
 	return NULL;
@@ -973,8 +975,8 @@ static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
 					phys_to_virt(base));
 		}
 
-	free_pages((unsigned long)domain->pgtable, 2);
-	free_pages((unsigned long)domain->lv2entcnt, 1);
+	iommu_free_pages(domain->pgtable, 2);
+	iommu_free_pages(domain->lv2entcnt, 1);
 	kfree(domain);
 }
 
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 07/11] iommu/rockchip: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/rockchip-iommu.c to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/rockchip-iommu.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 2685861c0a12..e04f22d481d0 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -26,6 +26,8 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+#include "iommu-pages.h"
+
 /** MMU register offsets */
 #define RK_MMU_DTE_ADDR		0x00	/* Directory table address */
 #define RK_MMU_STATUS		0x04
@@ -727,14 +729,14 @@ static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
 	if (rk_dte_is_pt_valid(dte))
 		goto done;
 
-	page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | rk_ops->gfp_flags);
+	page_table = iommu_alloc_page(GFP_ATOMIC | rk_ops->gfp_flags);
 	if (!page_table)
 		return ERR_PTR(-ENOMEM);
 
 	pt_dma = dma_map_single(dma_dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE);
 	if (dma_mapping_error(dma_dev, pt_dma)) {
 		dev_err(dma_dev, "DMA mapping error while allocating page table\n");
-		free_page((unsigned long)page_table);
+		iommu_free_page(page_table);
 		return ERR_PTR(-ENOMEM);
 	}
 
@@ -1061,7 +1063,7 @@ static struct iommu_domain *rk_iommu_domain_alloc_paging(struct device *dev)
 	 * Each level1 (dt) and level2 (pt) table has 1024 4-byte entries.
 	 * Allocate one 4 KiB page for each table.
 	 */
-	rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | rk_ops->gfp_flags);
+	rk_domain->dt = iommu_alloc_page(GFP_KERNEL | rk_ops->gfp_flags);
 	if (!rk_domain->dt)
 		goto err_free_domain;
 
@@ -1083,7 +1085,7 @@ static struct iommu_domain *rk_iommu_domain_alloc_paging(struct device *dev)
 	return &rk_domain->domain;
 
 err_free_dt:
-	free_page((unsigned long)rk_domain->dt);
+	iommu_free_page(rk_domain->dt);
 err_free_domain:
 	kfree(rk_domain);
 
@@ -1104,13 +1106,13 @@ static void rk_iommu_domain_free(struct iommu_domain *domain)
 			u32 *page_table = phys_to_virt(pt_phys);
 			dma_unmap_single(dma_dev, pt_phys,
 					 SPAGE_SIZE, DMA_TO_DEVICE);
-			free_page((unsigned long)page_table);
+			iommu_free_page(page_table);
 		}
 	}
 
 	dma_unmap_single(dma_dev, rk_domain->dt_dma,
 			 SPAGE_SIZE, DMA_TO_DEVICE);
-	free_page((unsigned long)rk_domain->dt);
+	iommu_free_page(rk_domain->dt);
 
 	kfree(rk_domain);
 }
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 08/11] iommu/sun50i: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/sun50i-iommu.c to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/sun50i-iommu.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c
index 41484a5a399b..172ddb717eb5 100644
--- a/drivers/iommu/sun50i-iommu.c
+++ b/drivers/iommu/sun50i-iommu.c
@@ -26,6 +26,8 @@
 #include <linux/spinlock.h>
 #include <linux/types.h>
 
+#include "iommu-pages.h"
+
 #define IOMMU_RESET_REG			0x010
 #define IOMMU_RESET_RELEASE_ALL			0xffffffff
 #define IOMMU_ENABLE_REG		0x020
@@ -679,8 +681,7 @@ sun50i_iommu_domain_alloc_paging(struct device *dev)
 	if (!sun50i_domain)
 		return NULL;
 
-	sun50i_domain->dt = (u32 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
-						    get_order(DT_SIZE));
+	sun50i_domain->dt = iommu_alloc_pages(GFP_KERNEL, get_order(DT_SIZE));
 	if (!sun50i_domain->dt)
 		goto err_free_domain;
 
@@ -702,7 +703,7 @@ static void sun50i_iommu_domain_free(struct iommu_domain *domain)
 {
 	struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
 
-	free_pages((unsigned long)sun50i_domain->dt, get_order(DT_SIZE));
+	iommu_free_pages(sun50i_domain->dt, get_order(DT_SIZE));
 	sun50i_domain->dt = NULL;
 
 	kfree(sun50i_domain);
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 09/11] iommu/tegra-smmu: use page allocation function provided by iommu-pages.h

[Pasha Tatashin]

Convert iommu/tegra-smmu.c to use the new page allocation functions
provided in iommu-pages.h.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/tegra-smmu.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 310871728ab4..8be74d472f21 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -19,6 +19,8 @@
 #include <soc/tegra/ahb.h>
 #include <soc/tegra/mc.h>
 
+#include "iommu-pages.h"
+
 struct tegra_smmu_group {
 	struct list_head list;
 	struct tegra_smmu *smmu;
@@ -282,7 +284,7 @@ static struct iommu_domain *tegra_smmu_domain_alloc_paging(struct device *dev)
 
 	as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
 
-	as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
+	as->pd = __iommu_alloc_pages(GFP_KERNEL | __GFP_DMA, 0);
 	if (!as->pd) {
 		kfree(as);
 		return NULL;
@@ -290,7 +292,7 @@ static struct iommu_domain *tegra_smmu_domain_alloc_paging(struct device *dev)
 
 	as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
 	if (!as->count) {
-		__free_page(as->pd);
+		__iommu_free_pages(as->pd, 0);
 		kfree(as);
 		return NULL;
 	}
@@ -298,7 +300,7 @@ static struct iommu_domain *tegra_smmu_domain_alloc_paging(struct device *dev)
 	as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
 	if (!as->pts) {
 		kfree(as->count);
-		__free_page(as->pd);
+		__iommu_free_pages(as->pd, 0);
 		kfree(as);
 		return NULL;
 	}
@@ -599,14 +601,14 @@ static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
 		dma = dma_map_page(smmu->dev, page, 0, SMMU_SIZE_PT,
 				   DMA_TO_DEVICE);
 		if (dma_mapping_error(smmu->dev, dma)) {
-			__free_page(page);
+			__iommu_free_pages(page, 0);
 			return NULL;
 		}
 
 		if (!smmu_dma_addr_valid(smmu, dma)) {
 			dma_unmap_page(smmu->dev, dma, SMMU_SIZE_PT,
 				       DMA_TO_DEVICE);
-			__free_page(page);
+			__iommu_free_pages(page, 0);
 			return NULL;
 		}
 
@@ -649,7 +651,7 @@ static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
 		tegra_smmu_set_pde(as, iova, 0);
 
 		dma_unmap_page(smmu->dev, pte_dma, SMMU_SIZE_PT, DMA_TO_DEVICE);
-		__free_page(page);
+		__iommu_free_pages(page, 0);
 		as->pts[pde] = NULL;
 	}
 }
@@ -688,7 +690,7 @@ static struct page *as_get_pde_page(struct tegra_smmu_as *as,
 	if (gfpflags_allow_blocking(gfp))
 		spin_unlock_irqrestore(&as->lock, *flags);
 
-	page = alloc_page(gfp | __GFP_DMA | __GFP_ZERO);
+	page = __iommu_alloc_pages(gfp | __GFP_DMA, 0);
 
 	if (gfpflags_allow_blocking(gfp))
 		spin_lock_irqsave(&as->lock, *flags);
@@ -700,7 +702,7 @@ static struct page *as_get_pde_page(struct tegra_smmu_as *as,
 	 */
 	if (as->pts[pde]) {
 		if (page)
-			__free_page(page);
+			__iommu_free_pages(page, 0);
 
 		page = as->pts[pde];
 	}
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 10/11] iommu: observability of the IOMMU allocations

[Pasha Tatashin]

Add NR_IOMMU_PAGES into node_stat_item that counts number of pages
that are allocated by the IOMMU subsystem.

The allocations can be view per-node via:
/sys/devices/system/node/nodeN/vmstat.

For example:

$ grep iommu /sys/devices/system/node/node*/vmstat
/sys/devices/system/node/node0/vmstat:nr_iommu_pages 106025
/sys/devices/system/node/node1/vmstat:nr_iommu_pages 3464

The value is in page-count, therefore, in the above example
the iommu allocations amount to ~428M.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 drivers/iommu/iommu-pages.h | 30 ++++++++++++++++++++++++++++++
 include/linux/mmzone.h      |  3 +++
 mm/vmstat.c                 |  3 +++
 3 files changed, 36 insertions(+)

diff --git a/drivers/iommu/iommu-pages.h b/drivers/iommu/iommu-pages.h
index 35bfa369b134..daac2da00e40 100644
--- a/drivers/iommu/iommu-pages.h
+++ b/drivers/iommu/iommu-pages.h
@@ -20,6 +20,30 @@
  * large, i.e. multiple gigabytes in size.
  */
 
+/**
+ * __iommu_alloc_account - account for newly allocated page.
+ * @page: head struct page of the page.
+ * @order: order of the page
+ */
+static inline void __iommu_alloc_account(struct page *page, int order)
+{
+	const long pgcnt = 1l << order;
+
+	mod_node_page_state(page_pgdat(page), NR_IOMMU_PAGES, pgcnt);
+}
+
+/**
+ * __iommu_free_account - account a page that is about to be freed.
+ * @page: head struct page of the page.
+ * @order: order of the page
+ */
+static inline void __iommu_free_account(struct page *page, int order)
+{
+	const long pgcnt = 1l << order;
+
+	mod_node_page_state(page_pgdat(page), NR_IOMMU_PAGES, -pgcnt);
+}
+
 /**
  * __iommu_alloc_pages - allocate a zeroed page of a given order.
  * @gfp: buddy allocator flags
@@ -35,6 +59,8 @@ static inline struct page *__iommu_alloc_pages(gfp_t gfp, int order)
 	if (unlikely(!page))
 		return NULL;
 
+	__iommu_alloc_account(page, order);
+
 	return page;
 }
 
@@ -48,6 +74,7 @@ static inline void __iommu_free_pages(struct page *page, int order)
 	if (!page)
 		return;
 
+	__iommu_free_account(page, order);
 	__free_pages(page, order);
 }
 
@@ -67,6 +94,8 @@ static inline void *iommu_alloc_pages_node(int nid, gfp_t gfp, int order)
 	if (unlikely(!page))
 		return NULL;
 
+	__iommu_alloc_account(page, order);
+
 	return page_address(page);
 }
 
@@ -147,6 +176,7 @@ static inline void iommu_put_pages_list(struct list_head *page)
 		struct page *p = list_entry(page->prev, struct page, lru);
 
 		list_del(&p->lru);
+		__iommu_free_account(p, 0);
 		put_page(p);
 	}
 }
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index a497f189d988..bb6bc504915a 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -203,6 +203,9 @@ enum node_stat_item {
 #endif
 	NR_PAGETABLE,		/* used for pagetables */
 	NR_SECONDARY_PAGETABLE, /* secondary pagetables, e.g. KVM pagetables */
+#ifdef CONFIG_IOMMU_SUPPORT
+	NR_IOMMU_PAGES,		/* # of pages allocated by IOMMU */
+#endif
 #ifdef CONFIG_SWAP
 	NR_SWAPCACHE,
 #endif
diff --git a/mm/vmstat.c b/mm/vmstat.c
index db79935e4a54..8507c497218b 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1242,6 +1242,9 @@ const char * const vmstat_text[] = {
 #endif
 	"nr_page_table_pages",
 	"nr_sec_page_table_pages",
+#ifdef CONFIG_IOMMU_SUPPORT
+	"nr_iommu_pages",
+#endif
 #ifdef CONFIG_SWAP
 	"nr_swapcached",
 #endif
-- 
2.44.0.rc0.258.g7320e95886-goog

[PATCH v5 11/11] iommu: account IOMMU allocated memory

[Pasha Tatashin]

In order to be able to limit the amount of memory that is allocated
by IOMMU subsystem, the memory must be accounted.

Account IOMMU as part of the secondary pagetables as it was discussed
at LPC.

The value of SecPageTables now contains mmeory allocation by IOMMU
and KVM.

There is a difference between GFP_ACCOUNT and what NR_IOMMU_PAGES shows.
GFP_ACCOUNT is set only where it makes sense to charge to user
processes, i.e. IOMMU Page Tables, but there more IOMMU shared data
that should not really be charged to a specific process.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
 Documentation/admin-guide/cgroup-v2.rst | 2 +-
 Documentation/filesystems/proc.rst      | 4 ++--
 drivers/iommu/iommu-pages.h             | 2 ++
 include/linux/mmzone.h                  | 2 +-
 4 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 17e6e9565156..15f80fea8df7 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1432,7 +1432,7 @@ PAGE_SIZE multiple when read back.
 	  sec_pagetables
 		Amount of memory allocated for secondary page tables,
 		this currently includes KVM mmu allocations on x86
-		and arm64.
+		and arm64 and IOMMU page tables.
 
 	  percpu (npn)
 		Amount of memory used for storing per-cpu kernel
diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
index 104c6d047d9b..604b2dccdc5a 100644
--- a/Documentation/filesystems/proc.rst
+++ b/Documentation/filesystems/proc.rst
@@ -1110,8 +1110,8 @@ KernelStack
 PageTables
               Memory consumed by userspace page tables
 SecPageTables
-              Memory consumed by secondary page tables, this currently
-              currently includes KVM mmu allocations on x86 and arm64.
+              Memory consumed by secondary page tables, this currently includes
+              KVM mmu and IOMMU allocations on x86 and arm64.
 NFS_Unstable
               Always zero. Previous counted pages which had been written to
               the server, but has not been committed to stable storage.
diff --git a/drivers/iommu/iommu-pages.h b/drivers/iommu/iommu-pages.h
index daac2da00e40..6df286931907 100644
--- a/drivers/iommu/iommu-pages.h
+++ b/drivers/iommu/iommu-pages.h
@@ -30,6 +30,7 @@ static inline void __iommu_alloc_account(struct page *page, int order)
 	const long pgcnt = 1l << order;
 
 	mod_node_page_state(page_pgdat(page), NR_IOMMU_PAGES, pgcnt);
+	mod_lruvec_page_state(page, NR_SECONDARY_PAGETABLE, pgcnt);
 }
 
 /**
@@ -42,6 +43,7 @@ static inline void __iommu_free_account(struct page *page, int order)
 	const long pgcnt = 1l << order;
 
 	mod_node_page_state(page_pgdat(page), NR_IOMMU_PAGES, -pgcnt);
+	mod_lruvec_page_state(page, NR_SECONDARY_PAGETABLE, -pgcnt);
 }
 
 /**
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index bb6bc504915a..a18edcf12d53 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -202,7 +202,7 @@ enum node_stat_item {
 	NR_KERNEL_SCS_KB,	/* measured in KiB */
 #endif
 	NR_PAGETABLE,		/* used for pagetables */
-	NR_SECONDARY_PAGETABLE, /* secondary pagetables, e.g. KVM pagetables */
+	NR_SECONDARY_PAGETABLE, /* secondary pagetables, KVM & IOMMU */
 #ifdef CONFIG_IOMMU_SUPPORT
 	NR_IOMMU_PAGES,		/* # of pages allocated by IOMMU */
 #endif
-- 
2.44.0.rc0.258.g7320e95886-goog

Re: [PATCH v5 02/11] iommu/dma: use iommu_put_pages_list() to releae freelist

[David Rientjes]

On Thu, 22 Feb 2024, Pasha Tatashin wrote:

> Free the IOMMU page tables via iommu_put_pages_list(). The page tables
> were allocated via iommu_alloc_* functions in architecture specific
> places, but are released in dma-iommu if the freelist is gathered during
> map/unmap operations into iommu_iotlb_gather data structure.
> 
> Currently, only iommu/intel that does that.
> 
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>

Acked-by: David Rientjes <rientjes@google.com>

Re: [PATCH v5 00/11] IOMMU memory observability

[David Rientjes]

On Thu, 22 Feb 2024, Pasha Tatashin wrote:

> Pasha Tatashin (11):
>   iommu/vt-d: add wrapper functions for page allocations
>   iommu/dma: use iommu_put_pages_list() to releae freelist
>   iommu/amd: use page allocation function provided by iommu-pages.h
>   iommu/io-pgtable-arm: use page allocation function provided by
>     iommu-pages.h
>   iommu/io-pgtable-dart: use page allocation function provided by
>     iommu-pages.h
>   iommu/exynos: use page allocation function provided by iommu-pages.h
>   iommu/rockchip: use page allocation function provided by iommu-pages.h
>   iommu/sun50i: use page allocation function provided by iommu-pages.h
>   iommu/tegra-smmu: use page allocation function provided by
>     iommu-pages.h
>   iommu: observability of the IOMMU allocations
>   iommu: account IOMMU allocated memory
> 
>  Documentation/admin-guide/cgroup-v2.rst |   2 +-
>  Documentation/filesystems/proc.rst      |   4 +-
>  drivers/iommu/amd/amd_iommu.h           |   8 -
>  drivers/iommu/amd/init.c                |  91 ++++++------
>  drivers/iommu/amd/io_pgtable.c          |  13 +-
>  drivers/iommu/amd/io_pgtable_v2.c       |  20 +--
>  drivers/iommu/amd/iommu.c               |  13 +-
>  drivers/iommu/dma-iommu.c               |   7 +-
>  drivers/iommu/exynos-iommu.c            |  14 +-
>  drivers/iommu/intel/dmar.c              |  16 +-
>  drivers/iommu/intel/iommu.c             |  47 ++----
>  drivers/iommu/intel/iommu.h             |   2 -
>  drivers/iommu/intel/irq_remapping.c     |  16 +-
>  drivers/iommu/intel/pasid.c             |  18 +--
>  drivers/iommu/intel/svm.c               |  11 +-
>  drivers/iommu/io-pgtable-arm.c          |  15 +-
>  drivers/iommu/io-pgtable-dart.c         |  37 ++---
>  drivers/iommu/iommu-pages.h             | 186 ++++++++++++++++++++++++
>  drivers/iommu/rockchip-iommu.c          |  14 +-
>  drivers/iommu/sun50i-iommu.c            |   7 +-
>  drivers/iommu/tegra-smmu.c              |  18 ++-
>  include/linux/mmzone.h                  |   5 +-
>  mm/vmstat.c                             |   3 +
>  23 files changed, 361 insertions(+), 206 deletions(-)
>  create mode 100644 drivers/iommu/iommu-pages.h
> 

Joerg, is this series anticipated to be queued up in the core branch of 
git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git so it gets into 
linux-next?

This observability seems particularly useful so that we can monitor and 
alert on any unexpected increases (unbounded memory growth from this 
subsystem has in the past caused us issues before the memory is otherwise 
not observable by host software).

Or are we still waiting on code reviews from some folks that we should 
ping?

Thanks!

Re: [PATCH v5 00/11] IOMMU memory observability

[Joerg Roedel]

Hi David,

On Fri, Mar 15, 2024 at 02:33:53PM -0700, David Rientjes wrote:
> Joerg, is this series anticipated to be queued up in the core branch of 
> git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git so it gets into 
> linux-next?
> 
> This observability seems particularly useful so that we can monitor and 
> alert on any unexpected increases (unbounded memory growth from this 
> subsystem has in the past caused us issues before the memory is otherwise 
> not observable by host software).
> 
> Or are we still waiting on code reviews from some folks that we should 
> ping?

A few more reviews would certainly help, but I will also do a review on
my own. If things are looking good I can merge it into the iommu tree
when 6.9-rc3 is released (which is the usual time I start merging new
stuff).

Regards,

	Joerg

Re: [PATCH v5 00/11] IOMMU memory observability

[Pasha Tatashin]

On Fri, Mar 15, 2024 at 5:53 PM Joerg Roedel <joro@8bytes.org> wrote:
>
> Hi David,
>
> On Fri, Mar 15, 2024 at 02:33:53PM -0700, David Rientjes wrote:
> > Joerg, is this series anticipated to be queued up in the core branch of
> > git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git so it gets into
> > linux-next?
> >
> > This observability seems particularly useful so that we can monitor and
> > alert on any unexpected increases (unbounded memory growth from this
> > subsystem has in the past caused us issues before the memory is otherwise
> > not observable by host software).
> >
> > Or are we still waiting on code reviews from some folks that we should
> > ping?
>
> A few more reviews would certainly help, but I will also do a review on
> my own. If things are looking good I can merge it into the iommu tree
> when 6.9-rc3 is released (which is the usual time I start merging new
> stuff).

Hi Joerg,

Would it make sense to stage this series in an unstable branch to get
more test coverage from the 0-day robots?

Thank you,
Pasha

Re: [PATCH v5 00/11] IOMMU memory observability

[Linu Cherian]

On 2024-02-22 at 23:09:26, Pasha Tatashin (pasha.tatashin@soleen.com) wrote:
> ----------------------------------------------------------------------
> Changelog
> ----------------------------------------------------------------------
> v5:
> - Synced with v6.8-rc5
> - Added: Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
> - Added: Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
> - Addressed review comments from Robin Murphy:
>   Updated the header comment in iommu-pages.h
>   Removed __iommu_alloc_pages_node(), invoke
>   iommu_alloc_pages_node directly.
>   Removed unused: __iommu_alloc_page_node()
>   Removed __iommu_free_page()
>   Renamed: iommu_free_pages_list() -> iommu_put_pages_list()
>   Added missing iommu_put_pages_list() to dma-iommu.c in
>   iommu/dma: use iommu_put_pages_list() to releae freelist
> 
> v4:
> - Synced with v6.8-rc3
> - Updated commit log for "iommu: account IOMMU allocated memory" as
>   suggested by Michal Koutný
> - Added more Acked-bys David Rientjes and Thierry Reding
> - Added Tested-by Bagas Sanjaya.
> 
> v3:
> - Sync with v6.7-rc7
> - Addressed comments from David Rientjes: s/pages/page/, added
>   unlikely() into the branches, expanded comment for
>   iommu_free_pages_list().
> - Added Acked-bys: David Rientjes
> 
> v2:
> - Added Reviewed-by Janne Grunau
> - Sync with 6.7.0-rc3
> - Separated form the series patches:
> vhost-vdpa: account iommu allocations
> https://lore.kernel.org/all/20231130200447.2319543-1-pasha.tatashin@soleen.com
> vfio: account iommu allocations
> https://lore.kernel.org/all/20231130200900.2320829-1-pasha.tatashin@soleen.com
> as suggested by Jason Gunthorpe
> - Fixed SPARC build issue detected by kernel test robot
> - Drop the following patches as they do account iommu page tables:
> iommu/dma: use page allocation function provided by iommu-pages.h
> iommu/fsl: use page allocation function provided by iommu-pages.h
> iommu/iommufd: use page allocation function provided by iommu-pages.h
> as suggested by Robin Murphy. These patches are not related to IOMMU
> page tables. We might need to do a separate work to support DMA
> observability.
> - Remove support iommu/io-pgtable-arm-v7s as the 2nd level pages are
> under a page size, thanks Robin Murphy for pointing this out.
> 
> ----------------------------------------------------------------------
> Description
> ----------------------------------------------------------------------
> IOMMU subsystem may contain state that is in gigabytes. Majority of that
> state is iommu page tables. Yet, there is currently, no way to observe
> how much memory is actually used by the iommu subsystem.
> 
> This patch series solves this problem by adding both observability to
> all pages that are allocated by IOMMU, and also accountability, so
> admins can limit the amount if via cgroups.
> 
> The system-wide observability is using /proc/meminfo:
> SecPageTables:    438176 kB
> 
> Contains IOMMU and KVM memory.

Can you please clarify what does KVM memory refers to here ?
Does it mean the VFIO map / virtio-iommu invoked ones for a guest VM?  

> 
> Per-node observability:
> /sys/devices/system/node/nodeN/meminfo
> Node N SecPageTables:    422204 kB
> 
> Contains IOMMU and KVM memory in the given NUMA node.
> 
> Per-node IOMMU only observability:
> /sys/devices/system/node/nodeN/vmstat
> nr_iommu_pages 105555
> 
> Contains number of pages IOMMU allocated in the given node.
> 
> Accountability: using sec_pagetables cgroup-v2 memory.stat entry.
> 
> With the change, iova_stress[1] stops as limit is reached:
> 
> $ ./iova_stress
> iova space:     0T      free memory:   497G
> iova space:     1T      free memory:   495G
> iova space:     2T      free memory:   493G
> iova space:     3T      free memory:   491G
> 
> stops as limit is reached.
> 
> This series encorporates suggestions that came from the discussion
> at LPC [2].
> ----------------------------------------------------------------------
> [1] https://github.com/soleen/iova_stress
> [2] https://lpc.events/event/17/contributions/1466
> ----------------------------------------------------------------------
> Previous versions
> v1: https://lore.kernel.org/all/20231128204938.1453583-1-pasha.tatashin@soleen.com
> v2: https://lore.kernel.org/linux-mm/20231130201504.2322355-1-pasha.tatashin@soleen.com
> v3: https://lore.kernel.org/all/20231226200205.562565-1-pasha.tatashin@soleen.com
> v4: https://lore.kernel.org/all/20240207174102.1486130-1-pasha.tatashin@soleen.com
> ----------------------------------------------------------------------
> 
> Pasha Tatashin (11):
>   iommu/vt-d: add wrapper functions for page allocations
>   iommu/dma: use iommu_put_pages_list() to releae freelist
>   iommu/amd: use page allocation function provided by iommu-pages.h
>   iommu/io-pgtable-arm: use page allocation function provided by
>     iommu-pages.h
>   iommu/io-pgtable-dart: use page allocation function provided by
>     iommu-pages.h
>   iommu/exynos: use page allocation function provided by iommu-pages.h
>   iommu/rockchip: use page allocation function provided by iommu-pages.h
>   iommu/sun50i: use page allocation function provided by iommu-pages.h
>   iommu/tegra-smmu: use page allocation function provided by
>     iommu-pages.h
>   iommu: observability of the IOMMU allocations
>   iommu: account IOMMU allocated memory
> 
>  Documentation/admin-guide/cgroup-v2.rst |   2 +-
>  Documentation/filesystems/proc.rst      |   4 +-
>  drivers/iommu/amd/amd_iommu.h           |   8 -
>  drivers/iommu/amd/init.c                |  91 ++++++------
>  drivers/iommu/amd/io_pgtable.c          |  13 +-
>  drivers/iommu/amd/io_pgtable_v2.c       |  20 +--
>  drivers/iommu/amd/iommu.c               |  13 +-
>  drivers/iommu/dma-iommu.c               |   7 +-
>  drivers/iommu/exynos-iommu.c            |  14 +-
>  drivers/iommu/intel/dmar.c              |  16 +-
>  drivers/iommu/intel/iommu.c             |  47 ++----
>  drivers/iommu/intel/iommu.h             |   2 -
>  drivers/iommu/intel/irq_remapping.c     |  16 +-
>  drivers/iommu/intel/pasid.c             |  18 +--
>  drivers/iommu/intel/svm.c               |  11 +-
>  drivers/iommu/io-pgtable-arm.c          |  15 +-
>  drivers/iommu/io-pgtable-dart.c         |  37 ++---
>  drivers/iommu/iommu-pages.h             | 186 ++++++++++++++++++++++++
>  drivers/iommu/rockchip-iommu.c          |  14 +-
>  drivers/iommu/sun50i-iommu.c            |   7 +-
>  drivers/iommu/tegra-smmu.c              |  18 ++-
>  include/linux/mmzone.h                  |   5 +-
>  mm/vmstat.c                             |   3 +
>  23 files changed, 361 insertions(+), 206 deletions(-)
>  create mode 100644 drivers/iommu/iommu-pages.h
> 
> -- 
> 2.44.0.rc0.258.g7320e95886-goog
> 

Re: [PATCH v5 01/11] iommu/vt-d: add wrapper functions for page allocations

[Linu Cherian]

Hi Pasha,

On 2024-02-22 at 23:09:27, Pasha Tatashin (pasha.tatashin@soleen.com) wrote:
> In order to improve observability and accountability of IOMMU layer, we
> must account the number of pages that are allocated by functions that
> are calling directly into buddy allocator.
> 
> This is achieved by first wrapping the allocation related functions into a
> separate inline functions in new file:
> 
> drivers/iommu/iommu-pages.h
> 
> Convert all page allocation calls under iommu/intel to use these new
> functions.
> 
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> Acked-by: David Rientjes <rientjes@google.com>
> Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
> ---
>  drivers/iommu/intel/dmar.c          |  16 +--
>  drivers/iommu/intel/iommu.c         |  47 +++------
>  drivers/iommu/intel/iommu.h         |   2 -
>  drivers/iommu/intel/irq_remapping.c |  16 +--
>  drivers/iommu/intel/pasid.c         |  18 ++--
>  drivers/iommu/intel/svm.c           |  11 +-
>  drivers/iommu/iommu-pages.h         | 154 ++++++++++++++++++++++++++++
>  7 files changed, 201 insertions(+), 63 deletions(-)
>  create mode 100644 drivers/iommu/iommu-pages.h


Few minor nits.

> 
> diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
> index 23cb80d62a9a..ff6045ae8e97 100644
> --- a/drivers/iommu/intel/dmar.c
> +++ b/drivers/iommu/intel/dmar.c
> @@ -32,6 +32,7 @@
>  
>  #include "iommu.h"
>  #include "../irq_remapping.h"
> +#include "../iommu-pages.h"
>  #include "perf.h"
>  #include "trace.h"
>  #include "perfmon.h"
> @@ -1185,7 +1186,7 @@ static void free_iommu(struct intel_iommu *iommu)
>  	}
>  
>  	if (iommu->qi) {
> -		free_page((unsigned long)iommu->qi->desc);
> +		iommu_free_page(iommu->qi->desc);
>  		kfree(iommu->qi->desc_status);
>  		kfree(iommu->qi);
>  	}
> @@ -1731,7 +1732,8 @@ static void __dmar_enable_qi(struct intel_iommu *iommu)
>  int dmar_enable_qi(struct intel_iommu *iommu)
>  {
>  	struct q_inval *qi;
> -	struct page *desc_page;
> +	void *desc;
> +	int order;
>  
>  	if (!ecap_qis(iommu->ecap))
>  		return -ENOENT;
> @@ -1752,19 +1754,19 @@ int dmar_enable_qi(struct intel_iommu *iommu)
>  	 * Need two pages to accommodate 256 descriptors of 256 bits each
>  	 * if the remapping hardware supports scalable mode translation.
>  	 */
> -	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
> -				     !!ecap_smts(iommu->ecap));
> -	if (!desc_page) {
> +	order = ecap_smts(iommu->ecap) ? 1 : 0;
> +	desc = iommu_alloc_pages_node(iommu->node, GFP_ATOMIC, order);
> +	if (!desc) {
>  		kfree(qi);
>  		iommu->qi = NULL;
>  		return -ENOMEM;
>  	}
>  
> -	qi->desc = page_address(desc_page);
> +	qi->desc = desc;
>  
>  	qi->desc_status = kcalloc(QI_LENGTH, sizeof(int), GFP_ATOMIC);
>  	if (!qi->desc_status) {
> -		free_page((unsigned long) qi->desc);
> +		iommu_free_page(qi->desc);
>  		kfree(qi);
>  		iommu->qi = NULL;
>  		return -ENOMEM;
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 6fb5f6fceea1..2c676f46e38c 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -28,6 +28,7 @@
>  #include "../dma-iommu.h"
>  #include "../irq_remapping.h"
>  #include "../iommu-sva.h"
> +#include "../iommu-pages.h"
>  #include "pasid.h"
>  #include "cap_audit.h"
>  #include "perfmon.h"
> @@ -224,22 +225,6 @@ static int __init intel_iommu_setup(char *str)
>  }
>  __setup("intel_iommu=", intel_iommu_setup);
>  
> -void *alloc_pgtable_page(int node, gfp_t gfp)
> -{
> -	struct page *page;
> -	void *vaddr = NULL;
> -
> -	page = alloc_pages_node(node, gfp | __GFP_ZERO, 0);
> -	if (page)
> -		vaddr = page_address(page);
> -	return vaddr;
> -}
> -
> -void free_pgtable_page(void *vaddr)
> -{
> -	free_page((unsigned long)vaddr);
> -}
> -
>  static int domain_type_is_si(struct dmar_domain *domain)
>  {
>  	return domain->domain.type == IOMMU_DOMAIN_IDENTITY;
> @@ -473,7 +458,7 @@ struct context_entry *iommu_context_addr(struct intel_iommu *iommu, u8 bus,
>  		if (!alloc)
>  			return NULL;
>  
> -		context = alloc_pgtable_page(iommu->node, GFP_ATOMIC);
> +		context = iommu_alloc_page_node(iommu->node, GFP_ATOMIC);
>  		if (!context)
>  			return NULL;
>  
> @@ -647,17 +632,17 @@ static void free_context_table(struct intel_iommu *iommu)
>  	for (i = 0; i < ROOT_ENTRY_NR; i++) {
>  		context = iommu_context_addr(iommu, i, 0, 0);
>  		if (context)
> -			free_pgtable_page(context);
> +			iommu_free_page(context);
>  
>  		if (!sm_supported(iommu))
>  			continue;
>  
>  		context = iommu_context_addr(iommu, i, 0x80, 0);
>  		if (context)
> -			free_pgtable_page(context);
> +			iommu_free_page(context);
>  	}
>  
> -	free_pgtable_page(iommu->root_entry);
> +	iommu_free_page(iommu->root_entry);
>  	iommu->root_entry = NULL;
>  }
>  
> @@ -795,7 +780,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
>  		if (!dma_pte_present(pte)) {
>  			uint64_t pteval;
>  
> -			tmp_page = alloc_pgtable_page(domain->nid, gfp);
> +			tmp_page = iommu_alloc_page_node(domain->nid, gfp);
>  
>  			if (!tmp_page)
>  				return NULL;
> @@ -807,7 +792,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
>  
>  			if (cmpxchg64(&pte->val, 0ULL, pteval))
>  				/* Someone else set it while we were thinking; use theirs. */
> -				free_pgtable_page(tmp_page);
> +				iommu_free_page(tmp_page);
>  			else
>  				domain_flush_cache(domain, pte, sizeof(*pte));
>  		}
> @@ -920,7 +905,7 @@ static void dma_pte_free_level(struct dmar_domain *domain, int level,
>  		      last_pfn < level_pfn + level_size(level) - 1)) {
>  			dma_clear_pte(pte);
>  			domain_flush_cache(domain, pte, sizeof(*pte));
> -			free_pgtable_page(level_pte);
> +			iommu_free_page(level_pte);
>  		}
>  next:
>  		pfn += level_size(level);
> @@ -944,7 +929,7 @@ static void dma_pte_free_pagetable(struct dmar_domain *domain,
>  
>  	/* free pgd */
>  	if (start_pfn == 0 && last_pfn == DOMAIN_MAX_PFN(domain->gaw)) {
> -		free_pgtable_page(domain->pgd);
> +		iommu_free_page(domain->pgd);
>  		domain->pgd = NULL;
>  	}
>  }
> @@ -1046,7 +1031,7 @@ static int iommu_alloc_root_entry(struct intel_iommu *iommu)
>  {
>  	struct root_entry *root;
>  
> -	root = alloc_pgtable_page(iommu->node, GFP_ATOMIC);
> +	root = iommu_alloc_page_node(iommu->node, GFP_ATOMIC);
>  	if (!root) {
>  		pr_err("Allocating root entry for %s failed\n",
>  			iommu->name);
> @@ -1718,7 +1703,7 @@ static void domain_exit(struct dmar_domain *domain)
>  		LIST_HEAD(freelist);
>  
>  		domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw), &freelist);
> -		put_pages_list(&freelist);
> +		iommu_put_pages_list(&freelist);
>  	}
>  
>  	if (WARN_ON(!list_empty(&domain->devices)))
> @@ -2452,7 +2437,7 @@ static int copy_context_table(struct intel_iommu *iommu,
>  			if (!old_ce)
>  				goto out;
>  
> -			new_ce = alloc_pgtable_page(iommu->node, GFP_KERNEL);
> +			new_ce = iommu_alloc_page_node(iommu->node, GFP_KERNEL);
>  			if (!new_ce)
>  				goto out_unmap;
>  
> @@ -3385,7 +3370,7 @@ static int intel_iommu_memory_notifier(struct notifier_block *nb,
>  					start_vpfn, mhp->nr_pages,
>  					list_empty(&freelist), 0);
>  			rcu_read_unlock();
> -			put_pages_list(&freelist);
> +			iommu_put_pages_list(&freelist);
>  		}
>  		break;
>  	}
> @@ -3816,7 +3801,7 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width)
>  	domain->max_addr = 0;
>  
>  	/* always allocate the top pgd */
> -	domain->pgd = alloc_pgtable_page(domain->nid, GFP_ATOMIC);
> +	domain->pgd = iommu_alloc_page_node(domain->nid, GFP_ATOMIC);
>  	if (!domain->pgd)
>  		return -ENOMEM;
>  	domain_flush_cache(domain, domain->pgd, PAGE_SIZE);
> @@ -3960,7 +3945,7 @@ int prepare_domain_attach_device(struct iommu_domain *domain,
>  		pte = dmar_domain->pgd;
>  		if (dma_pte_present(pte)) {
>  			dmar_domain->pgd = phys_to_virt(dma_pte_addr(pte));
> -			free_pgtable_page(pte);
> +			iommu_free_page(pte);
>  		}
>  		dmar_domain->agaw--;
>  	}
> @@ -4107,7 +4092,7 @@ static void intel_iommu_tlb_sync(struct iommu_domain *domain,
>  				      start_pfn, nrpages,
>  				      list_empty(&gather->freelist), 0);
>  
> -	put_pages_list(&gather->freelist);
> +	iommu_put_pages_list(&gather->freelist);
>  }
>  
>  static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
> diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
> index d02f916d8e59..9fe04cea29c4 100644
> --- a/drivers/iommu/intel/iommu.h
> +++ b/drivers/iommu/intel/iommu.h
> @@ -1069,8 +1069,6 @@ void domain_update_iommu_cap(struct dmar_domain *domain);
>  
>  int dmar_ir_support(void);
>  
> -void *alloc_pgtable_page(int node, gfp_t gfp);
> -void free_pgtable_page(void *vaddr);
>  void iommu_flush_write_buffer(struct intel_iommu *iommu);
>  struct iommu_domain *intel_nested_domain_alloc(struct iommu_domain *parent,
>  					       const struct iommu_user_data *user_data);
> diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c
> index 566297bc87dd..39cd9626eb8d 100644
> --- a/drivers/iommu/intel/irq_remapping.c
> +++ b/drivers/iommu/intel/irq_remapping.c
> @@ -22,6 +22,7 @@
>  
>  #include "iommu.h"
>  #include "../irq_remapping.h"
> +#include "../iommu-pages.h"
>  #include "cap_audit.h"
>  
>  enum irq_mode {
> @@ -527,7 +528,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
>  	struct ir_table *ir_table;
>  	struct fwnode_handle *fn;
>  	unsigned long *bitmap;
> -	struct page *pages;
> +	void *ir_table_base;
>  
>  	if (iommu->ir_table)
>  		return 0;
> @@ -536,9 +537,9 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
>  	if (!ir_table)
>  		return -ENOMEM;
>  
> -	pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO,
> -				 INTR_REMAP_PAGE_ORDER);
> -	if (!pages) {
> +	ir_table_base = iommu_alloc_pages_node(iommu->node, GFP_KERNEL,
> +					       INTR_REMAP_PAGE_ORDER);
> +	if (!ir_table_base) {
>  		pr_err("IR%d: failed to allocate pages of order %d\n",
>  		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
>  		goto out_free_table;
> @@ -573,7 +574,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
>  	else
>  		iommu->ir_domain->msi_parent_ops = &dmar_msi_parent_ops;
>  
> -	ir_table->base = page_address(pages);
> +	ir_table->base = ir_table_base;
>  	ir_table->bitmap = bitmap;
>  	iommu->ir_table = ir_table;
>  
> @@ -622,7 +623,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
>  out_free_bitmap:
>  	bitmap_free(bitmap);
>  out_free_pages:
> -	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
> +	iommu_free_pages(ir_table_base, INTR_REMAP_PAGE_ORDER);
>  out_free_table:
>  	kfree(ir_table);
>  
> @@ -643,8 +644,7 @@ static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
>  			irq_domain_free_fwnode(fn);
>  			iommu->ir_domain = NULL;
>  		}
> -		free_pages((unsigned long)iommu->ir_table->base,
> -			   INTR_REMAP_PAGE_ORDER);
> +		iommu_free_pages(iommu->ir_table->base, INTR_REMAP_PAGE_ORDER);
>  		bitmap_free(iommu->ir_table->bitmap);
>  		kfree(iommu->ir_table);
>  		iommu->ir_table = NULL;
> diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
> index 3239cefa4c33..d46f661dd971 100644
> --- a/drivers/iommu/intel/pasid.c
> +++ b/drivers/iommu/intel/pasid.c
> @@ -20,6 +20,7 @@
>  
>  #include "iommu.h"
>  #include "pasid.h"
> +#include "../iommu-pages.h"
>  
>  /*
>   * Intel IOMMU system wide PASID name space:
> @@ -38,7 +39,7 @@ int intel_pasid_alloc_table(struct device *dev)
>  {
>  	struct device_domain_info *info;
>  	struct pasid_table *pasid_table;
> -	struct page *pages;
> +	struct pasid_dir_entry *dir;
>  	u32 max_pasid = 0;
>  	int order, size;
>  
> @@ -59,14 +60,13 @@ int intel_pasid_alloc_table(struct device *dev)
>  
>  	size = max_pasid >> (PASID_PDE_SHIFT - 3);
>  	order = size ? get_order(size) : 0;
> -	pages = alloc_pages_node(info->iommu->node,
> -				 GFP_KERNEL | __GFP_ZERO, order);
> -	if (!pages) {
> +	dir = iommu_alloc_pages_node(info->iommu->node, GFP_KERNEL, order);
> +	if (!dir) {
>  		kfree(pasid_table);
>  		return -ENOMEM;
>  	}
>  
> -	pasid_table->table = page_address(pages);
> +	pasid_table->table = dir;
>  	pasid_table->order = order;
>  	pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
>  	info->pasid_table = pasid_table;
> @@ -97,10 +97,10 @@ void intel_pasid_free_table(struct device *dev)
>  	max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
>  	for (i = 0; i < max_pde; i++) {
>  		table = get_pasid_table_from_pde(&dir[i]);
> -		free_pgtable_page(table);
> +		iommu_free_page(table);
>  	}
>  
> -	free_pages((unsigned long)pasid_table->table, pasid_table->order);
> +	iommu_free_pages(pasid_table->table, pasid_table->order);
>  	kfree(pasid_table);
>  }
>  
> @@ -146,7 +146,7 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
>  retry:
>  	entries = get_pasid_table_from_pde(&dir[dir_index]);
>  	if (!entries) {
> -		entries = alloc_pgtable_page(info->iommu->node, GFP_ATOMIC);
> +		entries = iommu_alloc_page_node(info->iommu->node, GFP_ATOMIC);
>  		if (!entries)
>  			return NULL;
>  
> @@ -158,7 +158,7 @@ static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
>  		 */
>  		if (cmpxchg64(&dir[dir_index].val, 0ULL,
>  			      (u64)virt_to_phys(entries) | PASID_PTE_PRESENT)) {
> -			free_pgtable_page(entries);
> +			iommu_free_page(entries);
>  			goto retry;
>  		}
>  		if (!ecap_coherent(info->iommu->ecap)) {
> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
> index 40edd282903f..a691f917456c 100644
> --- a/drivers/iommu/intel/svm.c
> +++ b/drivers/iommu/intel/svm.c
> @@ -23,6 +23,7 @@
>  #include "pasid.h"
>  #include "perf.h"
>  #include "../iommu-sva.h"
> +#include "../iommu-pages.h"
>  #include "trace.h"
>  
>  static irqreturn_t prq_event_thread(int irq, void *d);
> @@ -64,16 +65,14 @@ svm_lookup_device_by_dev(struct intel_svm *svm, struct device *dev)
>  int intel_svm_enable_prq(struct intel_iommu *iommu)
>  {
>  	struct iopf_queue *iopfq;
> -	struct page *pages;
>  	int irq, ret;
>  
> -	pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, PRQ_ORDER);
> -	if (!pages) {
> +	iommu->prq = iommu_alloc_pages(GFP_KERNEL, PRQ_ORDER);
> +	if (!iommu->prq) {
>  		pr_warn("IOMMU: %s: Failed to allocate page request queue\n",
>  			iommu->name);
>  		return -ENOMEM;
>  	}
> -	iommu->prq = page_address(pages);
>  
>  	irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PRQ + iommu->seq_id, iommu->node, iommu);
>  	if (irq <= 0) {
> @@ -118,7 +117,7 @@ int intel_svm_enable_prq(struct intel_iommu *iommu)
>  	dmar_free_hwirq(irq);
>  	iommu->pr_irq = 0;
>  free_prq:
> -	free_pages((unsigned long)iommu->prq, PRQ_ORDER);
> +	iommu_free_pages(iommu->prq, PRQ_ORDER);
>  	iommu->prq = NULL;
>  
>  	return ret;
> @@ -141,7 +140,7 @@ int intel_svm_finish_prq(struct intel_iommu *iommu)
>  		iommu->iopf_queue = NULL;
>  	}
>  
> -	free_pages((unsigned long)iommu->prq, PRQ_ORDER);
> +	iommu_free_pages(iommu->prq, PRQ_ORDER);
>  	iommu->prq = NULL;
>  
>  	return 0;
> diff --git a/drivers/iommu/iommu-pages.h b/drivers/iommu/iommu-pages.h
> new file mode 100644
> index 000000000000..35bfa369b134
> --- /dev/null
> +++ b/drivers/iommu/iommu-pages.h
> @@ -0,0 +1,154 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2024, Google LLC.
> + * Pasha Tatashin <pasha.tatashin@soleen.com>
> + */
> +
> +#ifndef __IOMMU_PAGES_H
> +#define __IOMMU_PAGES_H
> +
> +#include <linux/vmstat.h>
> +#include <linux/gfp.h>
> +#include <linux/mm.h>
> +
> +/*
> + * All page allocations that should be reported to as "iommu-pagetables" to
> + * userspace must use on of the functions below.  This includes allocations of
> + * page-tables and other per-iommu_domain configuration structures.

/s/use on/use one/?

> + *
> + * This is necessary for the proper accounting as IOMMU state can be rather
> + * large, i.e. multiple gigabytes in size.
> + */
> +
> +/**
> + * __iommu_alloc_pages - allocate a zeroed page of a given order.
> + * @gfp: buddy allocator flags

Shall we keep the comments generic here(avoid reference to allocator
algo)  ?

> + * @order: page order
> + *
> + * returns the head struct page of the allocated page.
> + */
> +static inline struct page *__iommu_alloc_pages(gfp_t gfp, int order)
> +{
> +	struct page *page;
> +
> +	page = alloc_pages(gfp | __GFP_ZERO, order);
> +	if (unlikely(!page))
> +		return NULL;
> +
> +	return page;
> +}
> +
> +/**
> + * __iommu_free_pages - free page of a given order
> + * @page: head struct page of the page
> + * @order: page order
> + */
> +static inline void __iommu_free_pages(struct page *page, int order)
> +{
> +	if (!page)
> +		return;
> +
> +	__free_pages(page, order);
> +}
> +
> +/**
> + * iommu_alloc_pages_node - allocate a zeroed page of a given order from
> + * specific NUMA node.
> + * @nid: memory NUMA node id
> + * @gfp: buddy allocator flags

Same here for this one and other references below.

> + * @order: page order
> + *
> + * returns the virtual address of the allocated page
> + */
> +static inline void *iommu_alloc_pages_node(int nid, gfp_t gfp, int order)
> +{
> +	struct page *page = alloc_pages_node(nid, gfp | __GFP_ZERO, order);
> +
> +	if (unlikely(!page))
> +		return NULL;
> +
> +	return page_address(page);
> +}
> +
> +/**
> + * iommu_alloc_pages - allocate a zeroed page of a given order
> + * @gfp: buddy allocator flags
> + * @order: page order
> + *
> + * returns the virtual address of the allocated page
> + */
> +static inline void *iommu_alloc_pages(gfp_t gfp, int order)
> +{
> +	struct page *page = __iommu_alloc_pages(gfp, order);
> +
> +	if (unlikely(!page))
> +		return NULL;
> +
> +	return page_address(page);
> +}
> +
> +/**
> + * iommu_alloc_page_node - allocate a zeroed page at specific NUMA node.
> + * @nid: memory NUMA node id
> + * @gfp: buddy allocator flags
> + *
> + * returns the virtual address of the allocated page
> + */
> +static inline void *iommu_alloc_page_node(int nid, gfp_t gfp)
> +{
> +	return iommu_alloc_pages_node(nid, gfp, 0);
> +}
> +
> +/**
> + * iommu_alloc_page - allocate a zeroed page
> + * @gfp: buddy allocator flags
> + *
> + * returns the virtual address of the allocated page
> + */
> +static inline void *iommu_alloc_page(gfp_t gfp)
> +{
> +	return iommu_alloc_pages(gfp, 0);
> +}
> +
> +/**
> + * iommu_free_pages - free page of a given order
> + * @virt: virtual address of the page to be freed.
> + * @order: page order
> + */
> +static inline void iommu_free_pages(void *virt, int order)
> +{
> +	if (!virt)
> +		return;
> +
> +	__iommu_free_pages(virt_to_page(virt), order);
> +}
> +
> +/**
> + * iommu_free_page - free page
> + * @virt: virtual address of the page to be freed.
> + */
> +static inline void iommu_free_page(void *virt)
> +{
> +	iommu_free_pages(virt, 0);
> +}
> +
> +/**
> + * iommu_put_pages_list - free a list of pages.
> + * @page: the head of the lru list to be freed.
> + *
> + * There are no locking requirement for these pages, as they are going to be
> + * put on a free list as soon as refcount reaches 0. Pages are put on this LRU
> + * list once they are removed from the IOMMU page tables. However, they can
> + * still be access through debugfs.
> + */
> +static inline void iommu_put_pages_list(struct list_head *page)
> +{
> +	while (!list_empty(page)) {
> +		struct page *p = list_entry(page->prev, struct page, lru);
> +
> +		list_del(&p->lru);
> +		put_page(p);
> +	}
> +}
> +
> +#endif	/* __IOMMU_PAGES_H */
> -- 
> 2.44.0.rc0.258.g7320e95886-goog
> 

Re: [PATCH v5 00/11] IOMMU memory observability

[Pasha Tatashin]

> > Description
> > ----------------------------------------------------------------------
> > IOMMU subsystem may contain state that is in gigabytes. Majority of that
> > state is iommu page tables. Yet, there is currently, no way to observe
> > how much memory is actually used by the iommu subsystem.
> >
> > This patch series solves this problem by adding both observability to
> > all pages that are allocated by IOMMU, and also accountability, so
> > admins can limit the amount if via cgroups.
> >
> > The system-wide observability is using /proc/meminfo:
> > SecPageTables:    438176 kB
> >
> > Contains IOMMU and KVM memory.
>
> Can you please clarify what does KVM memory refers to here ?
> Does it mean the VFIO map / virtio-iommu invoked ones for a guest VM?

This means that nested page tables that are managed by KVM, and device
page tables that are managed by IOMMU are all accounted in
SecPageTables (secondary page tables). The decision to account them
both in one field of meminfo was made at LPC'23.

Pasha

Re: [PATCH v5 01/11] iommu/vt-d: add wrapper functions for page allocations

[Pasha Tatashin]

> Few minor nits.

Hi Linu,

Thank you for taking a look at this patch, my replies below.

> > +/*
> > + * All page allocations that should be reported to as "iommu-pagetables" to
> > + * userspace must use on of the functions below.  This includes allocations of
> > + * page-tables and other per-iommu_domain configuration structures.
>
> /s/use on/use one/?

I will correct in the next version (if there is going to be one).

> > + *
> > + * This is necessary for the proper accounting as IOMMU state can be rather
> > + * large, i.e. multiple gigabytes in size.
> > + */
> > +
> > +/**
> > + * __iommu_alloc_pages - allocate a zeroed page of a given order.
> > + * @gfp: buddy allocator flags
>
> Shall we keep the comments generic here(avoid reference to allocator
> algo)  ?

There are no references to allocator algorithm. I specify the zero
page because this function adds __GFP_ZERO. The order and gfp
arguments are provided by the caller, therefore, should be mentioned.

> > + * @order: page order
> > + *
> > + * returns the head struct page of the allocated page.
> > + */
> > +static inline struct page *__iommu_alloc_pages(gfp_t gfp, int order)
> > +{
> > +     struct page *page;
> > +
> > +     page = alloc_pages(gfp | __GFP_ZERO, order);
> > +     if (unlikely(!page))
> > +             return NULL;
> > +
> > +     return page;
> > +}
> > +
> > +/**
> > + * __iommu_free_pages - free page of a given order
> > + * @page: head struct page of the page
> > + * @order: page order
> > + */
> > +static inline void __iommu_free_pages(struct page *page, int order)
> > +{
> > +     if (!page)
> > +             return;
> > +
> > +     __free_pages(page, order);
> > +}
> > +
> > +/**
> > + * iommu_alloc_pages_node - allocate a zeroed page of a given order from
> > + * specific NUMA node.
> > + * @nid: memory NUMA node id
> > + * @gfp: buddy allocator flags
>
> Same here for this one and other references below.

ditto.

Thank you,
Pasha

Re: [PATCH v5 01/11] iommu/vt-d: add wrapper functions for page allocations

[Linu Cherian]

Hi Pasha,

> -----Original Message-----
> From: Pasha Tatashin <pasha.tatashin@soleen.com>
> Sent: Thursday, April 4, 2024 7:26 PM
> To: Linu Cherian <lcherian@marvell.com>
> Cc: akpm@linux-foundation.org; alim.akhtar@samsung.com;
> alyssa@rosenzweig.io; asahi@lists.linux.dev; baolu.lu@linux.intel.com;
> bhelgaas@google.com; cgroups@vger.kernel.org; corbet@lwn.net;
> david@redhat.com; dwmw2@infradead.org; hannes@cmpxchg.org;
> heiko@sntech.de; iommu@lists.linux.dev; jernej.skrabec@gmail.com;
> jonathanh@nvidia.com; joro@8bytes.org; krzysztof.kozlowski@linaro.org;
> linux-doc@vger.kernel.org; linux-fsdevel@vger.kernel.org; linux-
> kernel@vger.kernel.org; linux-mm@kvack.org; linux-
> rockchip@lists.infradead.org; linux-samsung-soc@vger.kernel.org; linux-
> sunxi@lists.linux.dev; linux-tegra@vger.kernel.org;
> lizefan.x@bytedance.com; marcan@marcan.st; mhiramat@kernel.org;
> m.szyprowski@samsung.com; paulmck@kernel.org; rdunlap@infradead.org;
> robin.murphy@arm.com; samuel@sholland.org;
> suravee.suthikulpanit@amd.com; sven@svenpeter.dev;
> thierry.reding@gmail.com; tj@kernel.org; tomas.mudrunka@gmail.com;
> vdumpa@nvidia.com; wens@csie.org; will@kernel.org; yu-
> cheng.yu@intel.com; rientjes@google.com; bagasdotme@gmail.com;
> mkoutny@suse.com
> Subject: [EXTERNAL] Re: [PATCH v5 01/11] iommu/vt-d: add wrapper
> functions for page allocations
> 
> > Few minor nits.
> 
> Hi Linu,
> 
> Thank you for taking a look at this patch, my replies below.
> 
> > > +/*
> > > + * All page allocations that should be reported to as
> > > +"iommu-pagetables" to
> > > + * userspace must use on of the functions below.  This includes
> > > +allocations of
> > > + * page-tables and other per-iommu_domain configuration structures.
> >
> > /s/use on/use one/?
> 
> I will correct in the next version (if there is going to be one).
> 
> > > + *
> > > + * This is necessary for the proper accounting as IOMMU state can
> > > + be rather
> > > + * large, i.e. multiple gigabytes in size.
> > > + */
> > > +
> > > +/**
> > > + * __iommu_alloc_pages - allocate a zeroed page of a given order.
> > > + * @gfp: buddy allocator flags
> >
> > Shall we keep the comments generic here(avoid reference to allocator
> > algo)  ?
> 
> There are no references to allocator algorithm. I specify the zero page
> because this function adds __GFP_ZERO. The order and gfp arguments are
> provided by the caller, therefore, should be mentioned.

Just meant to remove the mention of "buddy allocator" in the above comments if I was not clear.
Ie. "* @gfp:  allocator flags"  instead of "* @gfp: buddy allocator flags" since that is allocator specific.

Thanks
Linu Cherian.

Re: [PATCH v5 00/11] IOMMU memory observability

[Joerg Roedel]

Pasha,

On Thu, Feb 22, 2024 at 05:39:26PM +0000, Pasha Tatashin wrote:
> Pasha Tatashin (11):
>   iommu/vt-d: add wrapper functions for page allocations
>   iommu/dma: use iommu_put_pages_list() to releae freelist
>   iommu/amd: use page allocation function provided by iommu-pages.h
>   iommu/io-pgtable-arm: use page allocation function provided by
>     iommu-pages.h
>   iommu/io-pgtable-dart: use page allocation function provided by
>     iommu-pages.h
>   iommu/exynos: use page allocation function provided by iommu-pages.h
>   iommu/rockchip: use page allocation function provided by iommu-pages.h
>   iommu/sun50i: use page allocation function provided by iommu-pages.h
>   iommu/tegra-smmu: use page allocation function provided by
>     iommu-pages.h
>   iommu: observability of the IOMMU allocations
>   iommu: account IOMMU allocated memory

Some problems with this:

  1. I get DKIM failures when downloading this patch-set with b4, can
     you please send them via a mailserver with working DKIM?

  2. They don't apply to v6.9-rc3. Please rebase to that version and
     are-send.

Thanks,

	Joerg

Re: [PATCH v5 00/11] IOMMU memory observability

[Pasha Tatashin]

> Some problems with this:
>
>   1. I get DKIM failures when downloading this patch-set with b4, can
>      you please send them via a mailserver with working DKIM?

I was in the process of migrating from google domains to a different
registrar, but I think now the issue is resolved. I will verify it.

>   2. They don't apply to v6.9-rc3. Please rebase to that version and
>      are-send.

I will.

Thanks,
Pasha