summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/include/asm/pci.h1
-rw-r--r--arch/s390/pci/pci.c11
-rw-r--r--arch/s390/pci/pci_event.c11
-rw-r--r--arch/s390/pci/pci_sysfs.c70
4 files changed, 63 insertions, 30 deletions
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index a54c2cc88c47..30820a649e6e 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -122,6 +122,7 @@ struct zpci_dev {
struct rcu_head rcu;
struct hotplug_slot hotplug_slot;
+ struct mutex state_lock; /* protect state changes */
enum zpci_state state;
u32 fid; /* function ID, used by sclp */
u32 fh; /* function handle, used by insn's */
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index dff609e8a2a0..17267f659d22 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -28,6 +28,7 @@
#include <linux/jump_label.h>
#include <linux/pci.h>
#include <linux/printk.h>
+#include <linux/lockdep.h>
#include <asm/isc.h>
#include <asm/airq.h>
@@ -730,12 +731,12 @@ EXPORT_SYMBOL_GPL(zpci_disable_device);
* equivalent to its state during boot when first probing a driver.
* Consequently after reset the PCI function requires re-initialization via the
* common PCI code including re-enabling IRQs via pci_alloc_irq_vectors()
- * and enabling the function via e.g.pci_enablde_device_flags().The caller
+ * and enabling the function via e.g. pci_enable_device_flags(). The caller
* must guard against concurrent reset attempts.
*
* In most cases this function should not be called directly but through
* pci_reset_function() or pci_reset_bus() which handle the save/restore and
- * locking.
+ * locking - asserted by lockdep.
*
* Return: 0 on success and an error value otherwise
*/
@@ -744,6 +745,7 @@ int zpci_hot_reset_device(struct zpci_dev *zdev)
u8 status;
int rc;
+ lockdep_assert_held(&zdev->state_lock);
zpci_dbg(3, "rst fid:%x, fh:%x\n", zdev->fid, zdev->fh);
if (zdev_enabled(zdev)) {
/* Disables device access, DMAs and IRQs (reset state) */
@@ -806,6 +808,7 @@ struct zpci_dev *zpci_create_device(u32 fid, u32 fh, enum zpci_state state)
zdev->state = state;
kref_init(&zdev->kref);
+ mutex_init(&zdev->state_lock);
mutex_init(&zdev->fmb_lock);
mutex_init(&zdev->kzdev_lock);
@@ -870,6 +873,10 @@ int zpci_deconfigure_device(struct zpci_dev *zdev)
{
int rc;
+ lockdep_assert_held(&zdev->state_lock);
+ if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
+ return 0;
+
if (zdev->zbus->bus)
zpci_bus_remove_device(zdev, false);
diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c
index 4d9773ef9e0a..a17804b0dab4 100644
--- a/arch/s390/pci/pci_event.c
+++ b/arch/s390/pci/pci_event.c
@@ -267,6 +267,7 @@ static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
zpci_err_hex(ccdf, sizeof(*ccdf));
if (zdev) {
+ mutex_lock(&zdev->state_lock);
zpci_update_fh(zdev, ccdf->fh);
if (zdev->zbus->bus)
pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
@@ -294,6 +295,8 @@ static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
}
pci_dev_put(pdev);
no_pdev:
+ if (zdev)
+ mutex_unlock(&zdev->state_lock);
zpci_zdev_put(zdev);
}
@@ -326,6 +329,10 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
zpci_dbg(3, "avl fid:%x, fh:%x, pec:%x\n",
ccdf->fid, ccdf->fh, ccdf->pec);
+
+ if (existing_zdev)
+ mutex_lock(&zdev->state_lock);
+
switch (ccdf->pec) {
case 0x0301: /* Reserved|Standby -> Configured */
if (!zdev) {
@@ -383,8 +390,10 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
default:
break;
}
- if (existing_zdev)
+ if (existing_zdev) {
+ mutex_unlock(&zdev->state_lock);
zpci_zdev_put(zdev);
+ }
}
void zpci_event_availability(void *data)
diff --git a/arch/s390/pci/pci_sysfs.c b/arch/s390/pci/pci_sysfs.c
index 8a7abac51816..a0b872b74fe3 100644
--- a/arch/s390/pci/pci_sysfs.c
+++ b/arch/s390/pci/pci_sysfs.c
@@ -49,6 +49,39 @@ static ssize_t mio_enabled_show(struct device *dev,
}
static DEVICE_ATTR_RO(mio_enabled);
+static int _do_recover(struct pci_dev *pdev, struct zpci_dev *zdev)
+{
+ u8 status;
+ int ret;
+
+ pci_stop_and_remove_bus_device(pdev);
+ if (zdev_enabled(zdev)) {
+ ret = zpci_disable_device(zdev);
+ /*
+ * Due to a z/VM vs LPAR inconsistency in the error
+ * state the FH may indicate an enabled device but
+ * disable says the device is already disabled don't
+ * treat it as an error here.
+ */
+ if (ret == -EINVAL)
+ ret = 0;
+ if (ret)
+ return ret;
+ }
+
+ ret = zpci_enable_device(zdev);
+ if (ret)
+ return ret;
+
+ if (zdev->dma_table) {
+ ret = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+ virt_to_phys(zdev->dma_table), &status);
+ if (ret)
+ zpci_disable_device(zdev);
+ }
+ return ret;
+}
+
static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -56,7 +89,6 @@ static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
struct pci_dev *pdev = to_pci_dev(dev);
struct zpci_dev *zdev = to_zpci(pdev);
int ret = 0;
- u8 status;
/* Can't use device_remove_self() here as that would lead us to lock
* the pci_rescan_remove_lock while holding the device' kernfs lock.
@@ -70,6 +102,12 @@ static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
*/
kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
WARN_ON_ONCE(!kn);
+
+ /* Device needs to be configured and state must not change */
+ mutex_lock(&zdev->state_lock);
+ if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
+ goto out;
+
/* device_remove_file() serializes concurrent calls ignoring all but
* the first
*/
@@ -82,35 +120,13 @@ static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
*/
pci_lock_rescan_remove();
if (pci_dev_is_added(pdev)) {
- pci_stop_and_remove_bus_device(pdev);
- if (zdev_enabled(zdev)) {
- ret = zpci_disable_device(zdev);
- /*
- * Due to a z/VM vs LPAR inconsistency in the error
- * state the FH may indicate an enabled device but
- * disable says the device is already disabled don't
- * treat it as an error here.
- */
- if (ret == -EINVAL)
- ret = 0;
- if (ret)
- goto out;
- }
-
- ret = zpci_enable_device(zdev);
- if (ret)
- goto out;
-
- if (zdev->dma_table) {
- ret = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
- virt_to_phys(zdev->dma_table), &status);
- if (ret)
- zpci_disable_device(zdev);
- }
+ ret = _do_recover(pdev, zdev);
}
-out:
pci_rescan_bus(zdev->zbus->bus);
pci_unlock_rescan_remove();
+
+out:
+ mutex_unlock(&zdev->state_lock);
if (kn)
sysfs_unbreak_active_protection(kn);
return ret ? ret : count;