[<prev] [next>] [day] [month] [year] [list]
Message-id: <20140314140243.853cb1fc76afdc7e713c58da@samsung.com>
Date: Fri, 14 Mar 2014 14:02:43 +0900
From: Cho KyongHo <pullip.cho@...sung.com>
To: Linux ARM Kernel <linux-arm-kernel@...ts.infradead.org>,
Linux DeviceTree <devicetree@...r.kernel.org>,
Linux IOMMU <iommu@...ts.linux-foundation.org>,
Linux Kernel <linux-kernel@...r.kernel.org>,
Linux Samsung SOC <linux-samsung-soc@...r.kernel.org>
Cc: Antonios Motakis <a.motakis@...tualopensystems.com>,
Grant Grundler <grundler@...omium.org>,
Joerg Roedel <joro@...tes.org>,
Kukjin Kim <kgene.kim@...sung.com>,
Prathyush <prathyush.k@...sung.com>,
Rahul Sharma <rahul.sharma@...sung.com>,
Sachin Kamat <sachin.kamat@...aro.org>,
Varun Sethi <Varun.Sethi@...escale.com>,
Sylwester Nawrocki <s.nawrocki@...sung.com>,
Tomasz Figa <t.figa@...sung.com>
Subject: [PATCH v11 03/27] iommu/exynos: change error handling when page table
update is failed
This patch changes not to panic on any error when updating page table.
Instead prints error messages with callstack.
Signed-off-by: Cho KyongHo <pullip.cho@...sung.com>
---
drivers/iommu/exynos-iommu.c | 58 ++++++++++++++++++++++++++++++++----------
1 file changed, 44 insertions(+), 14 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 1c3a397..4a74ed8 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -812,13 +812,18 @@ finish:
static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
short *pgcounter)
{
+ if (lv1ent_section(sent)) {
+ WARN(1, "Trying mapping on %#08lx mapped with 1MiB page", iova);
+ return ERR_PTR(-EADDRINUSE);
+ }
+
if (lv1ent_fault(sent)) {
unsigned long *pent;
pent = kzalloc(LV2TABLE_SIZE, GFP_ATOMIC);
BUG_ON((unsigned long)pent & (LV2TABLE_SIZE - 1));
if (!pent)
- return NULL;
+ return ERR_PTR(-ENOMEM);
*sent = mk_lv1ent_page(__pa(pent));
*pgcounter = NUM_LV2ENTRIES;
@@ -829,14 +834,21 @@ static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
return page_entry(sent, iova);
}
-static int lv1set_section(unsigned long *sent, phys_addr_t paddr, short *pgcnt)
+static int lv1set_section(unsigned long *sent, unsigned long iova,
+ phys_addr_t paddr, short *pgcnt)
{
- if (lv1ent_section(sent))
+ if (lv1ent_section(sent)) {
+ WARN(1, "Trying mapping on 1MiB@...8lx that is mapped",
+ iova);
return -EADDRINUSE;
+ }
if (lv1ent_page(sent)) {
- if (*pgcnt != NUM_LV2ENTRIES)
+ if (*pgcnt != NUM_LV2ENTRIES) {
+ WARN(1, "Trying mapping on 1MiB@...8lx that is mapped",
+ iova);
return -EADDRINUSE;
+ }
kfree(page_entry(sent, 0));
@@ -854,8 +866,10 @@ static int lv2set_page(unsigned long *pent, phys_addr_t paddr, size_t size,
short *pgcnt)
{
if (size == SPAGE_SIZE) {
- if (!lv2ent_fault(pent))
+ if (!lv2ent_fault(pent)) {
+ WARN(1, "Trying mapping on 4KiB where mapping exists");
return -EADDRINUSE;
+ }
*pent = mk_lv2ent_spage(paddr);
pgtable_flush(pent, pent + 1);
@@ -864,7 +878,10 @@ static int lv2set_page(unsigned long *pent, phys_addr_t paddr, size_t size,
int i;
for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
if (!lv2ent_fault(pent)) {
- memset(pent, 0, sizeof(*pent) * i);
+ WARN(1,
+ "Trying mapping on 64KiB where mapping exists");
+ if (i > 0)
+ memset(pent - i, 0, sizeof(*pent) * i);
return -EADDRINUSE;
}
@@ -892,7 +909,7 @@ static int exynos_iommu_map(struct iommu_domain *domain, unsigned long iova,
entry = section_entry(priv->pgtable, iova);
if (size == SECT_SIZE) {
- ret = lv1set_section(entry, paddr,
+ ret = lv1set_section(entry, iova, paddr,
&priv->lv2entcnt[lv1ent_offset(iova)]);
} else {
unsigned long *pent;
@@ -900,17 +917,16 @@ static int exynos_iommu_map(struct iommu_domain *domain, unsigned long iova,
pent = alloc_lv2entry(entry, iova,
&priv->lv2entcnt[lv1ent_offset(iova)]);
- if (!pent)
- ret = -ENOMEM;
+ if (IS_ERR(pent))
+ ret = PTR_ERR(pent);
else
ret = lv2set_page(pent, paddr, size,
&priv->lv2entcnt[lv1ent_offset(iova)]);
}
- if (ret) {
+ if (ret)
pr_debug("%s: Failed to map iova 0x%lx/0x%x bytes\n",
__func__, iova, size);
- }
spin_unlock_irqrestore(&priv->pgtablelock, flags);
@@ -924,6 +940,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
struct sysmmu_drvdata *data;
unsigned long flags;
unsigned long *ent;
+ size_t err_pgsize;
BUG_ON(priv->pgtable == NULL);
@@ -932,7 +949,10 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
ent = section_entry(priv->pgtable, iova);
if (lv1ent_section(ent)) {
- BUG_ON(size < SECT_SIZE);
+ if (size < SECT_SIZE) {
+ err_pgsize = SECT_SIZE;
+ goto err;
+ }
*ent = 0;
pgtable_flush(ent, ent + 1);
@@ -964,7 +984,10 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
}
/* lv1ent_large(ent) == true here */
- BUG_ON(size < LPAGE_SIZE);
+ if (size < LPAGE_SIZE) {
+ err_pgsize = LPAGE_SIZE;
+ goto err;
+ }
memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
@@ -979,8 +1002,15 @@ done:
sysmmu_tlb_invalidate_entry(data->dev, iova);
spin_unlock_irqrestore(&priv->lock, flags);
-
return size;
+err:
+ spin_unlock_irqrestore(&priv->pgtablelock, flags);
+
+ WARN(1,
+ "%s: Failed due to size(%#x) @ %#08lx is smaller than page size %#x\n",
+ __func__, size, iova, err_pgsize);
+
+ return 0;
}
static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *domain,
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists