habanalabs: add userptr_lookup node in debugfs

It is useful to have the ability to see which user address was pinned
to which physical address during the initial mapping. We already have
all that info stored, but no means to search this data (which may be
quite large).

Signed-off-by: Yuri Nudelman <ynudelman@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/drivers/misc/habanalabs/common/debugfs.c b/drivers/misc/habanalabs/common/debugfs.c
index 6a7df57883d9..985f1f3dbd20 100644
--- a/drivers/misc/habanalabs/common/debugfs.c
+++ b/drivers/misc/habanalabs/common/debugfs.c
@@ -320,6 +320,77 @@ static int vm_show(struct seq_file *s, void *data)
 	return 0;
 }
 
+static int userptr_lookup_show(struct seq_file *s, void *data)
+{
+	struct hl_debugfs_entry *entry = s->private;
+	struct hl_dbg_device_entry *dev_entry = entry->dev_entry;
+	struct scatterlist *sg;
+	struct hl_userptr *userptr;
+	bool first = true;
+	u64 total_npages, npages, sg_start, sg_end;
+	dma_addr_t dma_addr;
+	int i;
+
+	spin_lock(&dev_entry->userptr_spinlock);
+
+	list_for_each_entry(userptr, &dev_entry->userptr_list, debugfs_list) {
+		if (dev_entry->userptr_lookup >= userptr->addr &&
+		dev_entry->userptr_lookup < userptr->addr + userptr->size) {
+			total_npages = 0;
+			for_each_sg(userptr->sgt->sgl, sg, userptr->sgt->nents,
+					i) {
+				npages = hl_get_sg_info(sg, &dma_addr);
+				sg_start = userptr->addr +
+					total_npages * PAGE_SIZE;
+				sg_end = userptr->addr +
+					(total_npages + npages) * PAGE_SIZE;
+
+				if (dev_entry->userptr_lookup >= sg_start &&
+				    dev_entry->userptr_lookup < sg_end) {
+					dma_addr += (dev_entry->userptr_lookup -
+							sg_start);
+					if (first) {
+						first = false;
+						seq_puts(s, "\n");
+						seq_puts(s, " user virtual address         dma address       pid        region start     region size\n");
+						seq_puts(s, "---------------------------------------------------------------------------------------\n");
+					}
+					seq_printf(s, " 0x%-18llx  0x%-16llx  %-8u  0x%-16llx %-12llu\n",
+						dev_entry->userptr_lookup,
+						(u64)dma_addr, userptr->pid,
+						userptr->addr, userptr->size);
+				}
+				total_npages += npages;
+			}
+		}
+	}
+
+	spin_unlock(&dev_entry->userptr_spinlock);
+
+	if (!first)
+		seq_puts(s, "\n");
+
+	return 0;
+}
+
+static ssize_t userptr_lookup_write(struct file *file, const char __user *buf,
+		size_t count, loff_t *f_pos)
+{
+	struct seq_file *s = file->private_data;
+	struct hl_debugfs_entry *entry = s->private;
+	struct hl_dbg_device_entry *dev_entry = entry->dev_entry;
+	ssize_t rc;
+	u64 value;
+
+	rc = kstrtoull_from_user(buf, count, 16, &value);
+	if (rc)
+		return rc;
+
+	dev_entry->userptr_lookup = value;
+
+	return count;
+}
+
 static int mmu_show(struct seq_file *s, void *data)
 {
 	struct hl_debugfs_entry *entry = s->private;
@@ -1175,6 +1246,7 @@ static const struct hl_info_list hl_debugfs_list[] = {
 	{"command_submission_jobs", command_submission_jobs_show, NULL},
 	{"userptr", userptr_show, NULL},
 	{"vm", vm_show, NULL},
+	{"userptr_lookup", userptr_lookup_show, userptr_lookup_write},
 	{"mmu", mmu_show, mmu_asid_va_write},
 	{"engines", engines_show, NULL}
 };