[PATCH] ib/ehca: Catch failing ioremap()

From: Alexander Schmidt
Date: Mon Jul 05 2010 - 12:19:42 EST


When ioremap() fails with a NULL pointer, catch the error and pass it to the
caller of create_qp() or create_cq() instead of trying to dereference the NULL
pointer later on.

Signed-off-by: Alexander Schmidt <alexs@xxxxxxxxxxxxxxxxxx>
---

Hi Roland, another patch for 2.6.36...

drivers/infiniband/hw/ehca/hcp_if.c | 32 ++++++++++++++++++++++++++++----
drivers/infiniband/hw/ehca/hcp_phyp.c | 11 +++++------
drivers/infiniband/hw/ehca/hcp_phyp.h | 2 +-
3 files changed, 34 insertions(+), 11 deletions(-)

--- linux-2.6.orig/drivers/infiniband/hw/ehca/hcp_if.c
+++ linux-2.6/drivers/infiniband/hw/ehca/hcp_if.c
@@ -269,6 +269,7 @@ u64 hipz_h_alloc_resource_cq(const struc
struct ehca_cq *cq,
struct ehca_alloc_cq_parms *param)
{
+ int rc;
u64 ret;
unsigned long outs[PLPAR_HCALL9_BUFSIZE];

@@ -283,8 +284,19 @@ u64 hipz_h_alloc_resource_cq(const struc
param->act_nr_of_entries = (u32)outs[3];
param->act_pages = (u32)outs[4];

- if (ret == H_SUCCESS)
- hcp_galpas_ctor(&cq->galpas, 0, outs[5], outs[6]);
+ if (ret == H_SUCCESS) {
+ rc = hcp_galpas_ctor(&cq->galpas, 0, outs[5], outs[6]);
+ if (rc) {
+ ehca_gen_err("Could not establish HW access. rc=%d paddr=%#lx",
+ rc, outs[5]);
+
+ ehca_plpar_hcall_norets(H_FREE_RESOURCE,
+ adapter_handle.handle, /* r4 */
+ cq->ipz_cq_handle.handle, /* r5 */
+ 0, 0, 0, 0, 0);
+ ret = H_NO_MEM;
+ }
+ }

if (ret == H_NOT_ENOUGH_RESOURCES)
ehca_gen_err("Not enough resources. ret=%lli", ret);
@@ -295,6 +307,7 @@ u64 hipz_h_alloc_resource_cq(const struc
u64 hipz_h_alloc_resource_qp(const struct ipz_adapter_handle adapter_handle,
struct ehca_alloc_qp_parms *parms, int is_user)
{
+ int rc;
u64 ret;
u64 allocate_controls, max_r10_reg, r11, r12;
unsigned long outs[PLPAR_HCALL9_BUFSIZE];
@@ -358,8 +371,19 @@ u64 hipz_h_alloc_resource_qp(const struc
parms->rqueue.queue_size =
(u32)EHCA_BMASK_GET(H_ALL_RES_QP_RQUEUE_SIZE_PAGES, outs[4]);

- if (ret == H_SUCCESS)
- hcp_galpas_ctor(&parms->galpas, is_user, outs[6], outs[6]);
+ if (ret == H_SUCCESS) {
+ rc = hcp_galpas_ctor(&parms->galpas, is_user, outs[6], outs[6]);
+ if (rc) {
+ ehca_gen_err("Could not establish HW access. rc=%d paddr=%#lx",
+ rc, outs[6]);
+
+ ehca_plpar_hcall_norets(H_FREE_RESOURCE,
+ adapter_handle.handle, /* r4 */
+ parms->qp_handle.handle, /* r5 */
+ 0, 0, 0, 0, 0);
+ ret = H_NO_MEM;
+ }
+ }

if (ret == H_NOT_ENOUGH_RESOURCES)
ehca_gen_err("Not enough resources. ret=%lli", ret);
--- linux-2.6.orig/drivers/infiniband/hw/ehca/hcp_phyp.c
+++ linux-2.6/drivers/infiniband/hw/ehca/hcp_phyp.c
@@ -42,10 +42,9 @@
#include "ehca_classes.h"
#include "hipz_hw.h"

-int hcall_map_page(u64 physaddr, u64 *mapaddr)
+u64 hcall_map_page(u64 physaddr)
{
- *mapaddr = (u64)(ioremap(physaddr, EHCA_PAGESIZE));
- return 0;
+ return (u64)ioremap(physaddr, EHCA_PAGESIZE);
}

int hcall_unmap_page(u64 mapaddr)
@@ -58,9 +57,9 @@ int hcp_galpas_ctor(struct h_galpas *gal
u64 paddr_kernel, u64 paddr_user)
{
if (!is_user) {
- int ret = hcall_map_page(paddr_kernel, &galpas->kernel.fw_handle);
- if (ret)
- return ret;
+ galpas->kernel.fw_handle = hcall_map_page(paddr_kernel);
+ if (!galpas->kernel.fw_handle)
+ return -ENOMEM;
} else
galpas->kernel.fw_handle = 0;

--- linux-2.6.orig/drivers/infiniband/hw/ehca/hcp_phyp.h
+++ linux-2.6/drivers/infiniband/hw/ehca/hcp_phyp.h
@@ -83,7 +83,7 @@ int hcp_galpas_ctor(struct h_galpas *gal

int hcp_galpas_dtor(struct h_galpas *galpas);

-int hcall_map_page(u64 physaddr, u64 * mapaddr);
+u64 hcall_map_page(u64 physaddr);

int hcall_unmap_page(u64 mapaddr);

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