diff mbox series

[V2,5/5] PCI: Unify slot and bus reset API

Message ID 1529467995-28780-5-git-send-email-okaya@codeaurora.org
State Superseded
Delegated to: Bjorn Helgaas
Headers show
Series [V2,1/5] PCI: handle error return from pci_reset_bridge_secondary_bus() | expand

Commit Message

Sinan Kaya June 20, 2018, 4:12 a.m. UTC 
Drivers are expected to call pci_reset_slot() or pci_reset_bus() by
querying if a system supports hotplug or not. A survey showed that most
drivers don't do this and we are leaking hotplug capability to the
user.

Hide pci_slot_reset() from drivers and embed into pci_bus_reset().
Change pci_reset_bus() parameter from struct pci_bus to struct pci_dev.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 drivers/pci/pci.c   | 27 +++++++++++++++++++++++----
 include/linux/pci.h |  3 +--
 2 files changed, 24 insertions(+), 6 deletions(-)

Comments

kernel test robot June 20, 2018, 5:17 a.m. UTC | #1 
Hi Sinan,

I love your patch! Yet something to improve:

[auto build test ERROR on pci/next]
[also build test ERROR on v4.18-rc1 next-20180619]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Sinan-Kaya/PCI-handle-error-return-from-pci_reset_bridge_secondary_bus/20180620-121648
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: x86_64-allyesconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

   drivers/infiniband//hw/hfi1/pcie.c: In function 'trigger_sbr':
>> drivers/infiniband//hw/hfi1/pcie.c:908:23: error: passing argument 1 of 'pci_reset_bus' from incompatible pointer type [-Werror=incompatible-pointer-types]
     return pci_reset_bus(dev->bus);
                          ^~~
   In file included from drivers/infiniband//hw/hfi1/pcie.c:48:0:
   include/linux/pci.h:1099:5: note: expected 'struct pci_dev *' but argument is of type 'struct pci_bus *'
    int pci_reset_bus(struct pci_dev *dev);
        ^~~~~~~~~~~~~
   cc1: some warnings being treated as errors

vim +/pci_reset_bus +908 drivers/infiniband//hw/hfi1/pcie.c

77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  873  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  874  /*
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  875   * Trigger a secondary bus reset (SBR) on ourselves using our parent.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  876   *
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  877   * Based on pci_parent_bus_reset() which is not exported by the
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  878   * kernel core.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  879   */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  880  static int trigger_sbr(struct hfi1_devdata *dd)
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  881  {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  882  	struct pci_dev *dev = dd->pcidev;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  883  	struct pci_dev *pdev;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  884  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  885  	/* need a parent */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  886  	if (!dev->bus->self) {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  887  		dd_dev_err(dd, "%s: no parent device\n", __func__);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  888  		return -ENOTTY;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  889  	}
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  890  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  891  	/* should not be anyone else on the bus */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  892  	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  893  		if (pdev != dev) {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  894  			dd_dev_err(dd,
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  895  				   "%s: another device is on the same bus\n",
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  896  				   __func__);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  897  			return -ENOTTY;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  898  		}
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  899  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  900  	/*
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  901  	 * A secondary bus reset (SBR) issues a hot reset to our device.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  902  	 * The following routine does a 1s wait after the reset is dropped
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  903  	 * per PCI Trhfa (recovery time).  PCIe 3.0 section 6.6.1 -
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  904  	 * Conventional Reset, paragraph 3, line 35 also says that a 1s
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  905  	 * delay after a reset is required.  Per spec requirements,
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  906  	 * the link is either working or not after that point.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  907  	 */
f001109e drivers/infiniband/hw/hfi1/pcie.c Sinan Kaya       2018-06-20 @908  	return pci_reset_bus(dev->bus);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  909  }
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  910  

:::::: The code at line 908 was first introduced by commit
:::::: f001109e94b74baebb3621ce1c7ba114a858adb3 IB/hfi1: use pci_reset_bus() for initiating pci secondary bus reset

:::::: TO: Sinan Kaya <okaya@codeaurora.org>
:::::: CC: 0day robot <lkp@intel.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
kernel test robot June 21, 2018, 4:58 a.m. UTC | #2 
Hi Sinan,

I love your patch! Perhaps something to improve:

[auto build test WARNING on pci/next]
[also build test WARNING on v4.18-rc1 next-20180620]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Sinan-Kaya/PCI-handle-error-return-from-pci_reset_bridge_secondary_bus/20180620-121648
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
reproduce:
        # apt-get install sparse
        make ARCH=x86_64 allmodconfig
        make C=1 CF=-D__CHECK_ENDIAN__


sparse warnings: (new ones prefixed by >>)

>> drivers/infiniband/hw/hfi1/pcie.c:908:33: sparse: incorrect type in argument 1 (different base types) @@    expected struct pci_dev *dev @@    got struct pci_dev *dev @@
   drivers/infiniband/hw/hfi1/pcie.c:908:33:    expected struct pci_dev *dev
   drivers/infiniband/hw/hfi1/pcie.c:908:33:    got struct pci_bus *bus
   drivers/infiniband/hw/hfi1/pcie.c: In function 'trigger_sbr':
   drivers/infiniband/hw/hfi1/pcie.c:908:23: error: passing argument 1 of 'pci_reset_bus' from incompatible pointer type [-Werror=incompatible-pointer-types]
     return pci_reset_bus(dev->bus);
                          ^~~
   In file included from drivers/infiniband/hw/hfi1/pcie.c:48:0:
   include/linux/pci.h:1099:5: note: expected 'struct pci_dev *' but argument is of type 'struct pci_bus *'
    int pci_reset_bus(struct pci_dev *dev);
        ^~~~~~~~~~~~~
   cc1: some warnings being treated as errors

vim +908 drivers/infiniband/hw/hfi1/pcie.c

77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  873  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  874  /*
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  875   * Trigger a secondary bus reset (SBR) on ourselves using our parent.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  876   *
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  877   * Based on pci_parent_bus_reset() which is not exported by the
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  878   * kernel core.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  879   */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  880  static int trigger_sbr(struct hfi1_devdata *dd)
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  881  {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  882  	struct pci_dev *dev = dd->pcidev;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  883  	struct pci_dev *pdev;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  884  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  885  	/* need a parent */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  886  	if (!dev->bus->self) {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  887  		dd_dev_err(dd, "%s: no parent device\n", __func__);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  888  		return -ENOTTY;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  889  	}
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  890  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  891  	/* should not be anyone else on the bus */
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  892  	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  893  		if (pdev != dev) {
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  894  			dd_dev_err(dd,
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  895  				   "%s: another device is on the same bus\n",
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  896  				   __func__);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  897  			return -ENOTTY;
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  898  		}
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  899  
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  900  	/*
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  901  	 * A secondary bus reset (SBR) issues a hot reset to our device.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  902  	 * The following routine does a 1s wait after the reset is dropped
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  903  	 * per PCI Trhfa (recovery time).  PCIe 3.0 section 6.6.1 -
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  904  	 * Conventional Reset, paragraph 3, line 35 also says that a 1s
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  905  	 * delay after a reset is required.  Per spec requirements,
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  906  	 * the link is either working or not after that point.
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  907  	 */
f001109e drivers/infiniband/hw/hfi1/pcie.c Sinan Kaya       2018-06-20 @908  	return pci_reset_bus(dev->bus);
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  909  }
77241056 drivers/staging/rdma/hfi1/pcie.c  Mike Marciniszyn 2015-07-30  910  

:::::: The code at line 908 was first introduced by commit
:::::: f001109e94b74baebb3621ce1c7ba114a858adb3 IB/hfi1: use pci_reset_bus() for initiating pci secondary bus reset

:::::: TO: Sinan Kaya <okaya@codeaurora.org>
:::::: CC: 0day robot <lkp@intel.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox series

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 79a1566..a44b948 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4798,7 +4798,7 @@  EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
  *
  * Return 0 on success, non-zero on error.
  */
-int pci_reset_slot(struct pci_slot *slot)
+static int __pci_reset_slot(struct pci_slot *slot)
 {
 	int rc;
 
@@ -4814,7 +4814,6 @@  int pci_reset_slot(struct pci_slot *slot)
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(pci_reset_slot);
 
 /**
  * __pci_try_reset_slot - Try to reset a PCI slot
@@ -4878,7 +4877,7 @@  int pci_probe_reset_bus(struct pci_bus *bus)
 EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
 
 /**
- * pci_reset_bus - reset a PCI bus
+ * __pci_reset_bus - reset a PCI bus
  * @bus: top level PCI bus to reset
  *
  * Do a bus reset on the given bus and any subordinate buses, saving
@@ -4886,7 +4885,7 @@  EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
  *
  * Return 0 on success, non-zero on error.
  */
-int pci_reset_bus(struct pci_bus *bus)
+static int __pci_reset_bus(struct pci_bus *bus)
 {
 	int rc;
 
@@ -4902,6 +4901,26 @@  int pci_reset_bus(struct pci_bus *bus)
 
 	return rc;
 }
+
+/**
+ * pci_reset_bus - reset a PCI bus
+ * @pdev: top level PCI device to reset via slot/bus
+ *
+ * Do a slot/bus reset on the given bus and any subordinate buses, saving
+ * and restoring state of all devices.
+ *
+ * Return 0 on success, non-zero on error.
+ */
+int pci_reset_bus(struct pci_dev *pdev)
+{
+	bool slot = false;
+
+	if (!pci_probe_reset_slot(pdev->slot))
+		slot = true;
+
+	return slot ? __pci_reset_slot(pdev->slot) :
+			__pci_reset_bus(pdev->bus);
+}
 EXPORT_SYMBOL_GPL(pci_reset_bus);
 
 /**
diff --git a/include/linux/pci.h b/include/linux/pci.h
index f5c85b6..e68ca2e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1095,9 +1095,8 @@  int pci_reset_function(struct pci_dev *dev);
 int pci_reset_function_locked(struct pci_dev *dev);
 int pci_try_reset_function(struct pci_dev *dev);
 int pci_probe_reset_slot(struct pci_slot *slot);
-int pci_reset_slot(struct pci_slot *slot);
 int pci_probe_reset_bus(struct pci_bus *bus);
-int pci_reset_bus(struct pci_bus *bus);
+int pci_reset_bus(struct pci_dev *dev);
 int pci_try_reset_bus(struct pci_dev *dev);
 void pci_reset_secondary_bus(struct pci_dev *dev);
 void pcibios_reset_secondary_bus(struct pci_dev *dev);