iommu/iova: add iova procfs for each dma iommu

Tested on RK3588 EVB1: localhost# ls /proc/iova/ av1d-master fdb90000.jpegd fdbb0000.iep fdcb0000.rkisp fdab0000.npu fdba0000.jpege-core fdbd0000.rkvenc-core fdce0000.rkcif fdb50400.vdpu fdba4000.jpege-core fdbe0000.rkvenc-core fdd90000.vop fdb60000.rga fdba8000.jpege-core fdc38100.rkvdec-core rkcif-mipi-lvds fdb70000.rga fdbac000.jpege-core fdc48100.rkvdec-core localhost# cat /proc/iova/fdc38100.rkvdec-core/used 0: [0x00000000ffe00000..0x00000000ffeff000] 1024KiB (4094 - 4095)MiB 1: [0x00000000fff00000..0x00000000fffff000] 1024KiB (4095 - 4096)MiB used: 2 MiB Signed-off-by: Jianqun Xu <[email protected]> Change-Id: I102e08243b5a0a4cd173e75e2e25f68f1f5b09b6
friendlyarm · Jun 30, 2022 · 4fe5523 · 4fe5523
1 parent 02382af
commit 4fe5523
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diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
@@ -1249,6 +1249,13 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size)
 		dev->dma_ops = &iommu_dma_ops;
 	}
 
+	if (domain->type == IOMMU_DOMAIN_DMA) {
+		struct iommu_dma_cookie *cookie = domain->iova_cookie;
+		struct iova_domain *iovad = &cookie->iovad;
+
+		init_iova_domain_procfs(iovad, dev_name(dev));
+	}
+
 	return;
 out_err:
 	 pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
@@ -11,6 +11,8 @@
 #include <linux/smp.h>
 #include <linux/bitops.h>
 #include <linux/cpu.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 
 /* The anchor node sits above the top of the usable address space */
 #define IOVA_ANCHOR	~0UL
@@ -27,6 +29,63 @@ static void fq_destroy_all_entries(struct iova_domain *iovad);
 static void fq_flush_timeout(struct timer_list *t);
 static void iova_dump(struct iova_domain *iovad);
 
+static int iova_used_show(struct seq_file *s, void *v)
+{
+	struct iova_domain *iovad = s->private;
+	struct iova *iova, *t;
+	unsigned long flags, cpu;
+	unsigned long used_pfn = 0;
+	int i = 0;
+
+	for_each_online_cpu(cpu)
+		free_cpu_cached_iovas(cpu, iovad);
+	free_global_cached_iovas(iovad);
+
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	rbtree_postorder_for_each_entry_safe(iova, t, &iovad->rbroot, node) {
+		dma_addr_t start = iova->pfn_lo << iova_shift(iovad);
+		dma_addr_t end = iova->pfn_hi << iova_shift(iovad);
+		unsigned long pfn = iova->pfn_hi + 1 - iova->pfn_lo;
+
+		if ((iova->pfn_hi == IOVA_ANCHOR) || (iova->pfn_lo == IOVA_ANCHOR))
+			continue;
+
+		seq_printf(s, "%4d: [%pad..%pad] %6luKiB (%4lu - %4lu)MiB\n",
+			   i++, &start, &end,
+			   pfn << (PAGE_SHIFT - 10),
+			   iova->pfn_lo >> (20 - PAGE_SHIFT),
+			   (iova->pfn_hi + 1) >> (20 - PAGE_SHIFT));
+		used_pfn += pfn;
+	}
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+	seq_printf(s, "used: %lu MiB\n", used_pfn >> (20 - PAGE_SHIFT));
+
+	return 0;
+}
+
+static struct proc_dir_entry *iova_dir;
+
+void init_iova_domain_procfs(struct iova_domain *iovad, const char *name)
+{
+	struct proc_dir_entry *root;
+
+	root = proc_mkdir(name, iova_dir);
+	if (!root)
+		return;
+
+	proc_create_single_data("used", 0, root, iova_used_show, iovad);
+}
+EXPORT_SYMBOL_GPL(init_iova_domain_procfs);
+
+static int __init iova_procfs_create(void)
+{
+	if (!iova_dir)
+		iova_dir = proc_mkdir("iova", NULL);
+
+	return 0;
+}
+subsys_initcall(iova_procfs_create);
+
 void
 init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 	unsigned long start_pfn)

diff --git a/include/linux/iova.h b/include/linux/iova.h
@@ -156,6 +156,7 @@ struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 	unsigned long start_pfn);
+void init_iova_domain_procfs(struct iova_domain *iovad, const char *name);
 bool has_iova_flush_queue(struct iova_domain *iovad);
 int init_iova_flush_queue(struct iova_domain *iovad,
 			  iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
@@ -238,6 +239,11 @@ static inline void init_iova_domain(struct iova_domain *iovad,
 {
 }
 
+static inline void
+init_iova_domain_procfs(struct iova_domain *iovad, const char *name)
+{
+}
+
 static inline bool has_iova_flush_queue(struct iova_domain *iovad)
 {
 	return false;