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-rw-r--r--drivers/pci/access.c74
-rw-r--r--drivers/pci/iov.c12
-rw-r--r--drivers/pci/pci.c4
3 files changed, 56 insertions, 34 deletions
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index fdaa42aac7c6..0c4c71712dfc 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -127,20 +127,20 @@ EXPORT_SYMBOL(pci_write_vpd);
* We have a bit per device to indicate it's blocked and a global wait queue
* for callers to sleep on until devices are unblocked.
*/
-static DECLARE_WAIT_QUEUE_HEAD(pci_ucfg_wait);
+static DECLARE_WAIT_QUEUE_HEAD(pci_cfg_wait);
-static noinline void pci_wait_ucfg(struct pci_dev *dev)
+static noinline void pci_wait_cfg(struct pci_dev *dev)
{
DECLARE_WAITQUEUE(wait, current);
- __add_wait_queue(&pci_ucfg_wait, &wait);
+ __add_wait_queue(&pci_cfg_wait, &wait);
do {
set_current_state(TASK_UNINTERRUPTIBLE);
raw_spin_unlock_irq(&pci_lock);
schedule();
raw_spin_lock_irq(&pci_lock);
- } while (dev->block_ucfg_access);
- __remove_wait_queue(&pci_ucfg_wait, &wait);
+ } while (dev->block_cfg_access);
+ __remove_wait_queue(&pci_cfg_wait, &wait);
}
/* Returns 0 on success, negative values indicate error. */
@@ -153,7 +153,8 @@ int pci_user_read_config_##size \
if (PCI_##size##_BAD) \
return -EINVAL; \
raw_spin_lock_irq(&pci_lock); \
- if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev); \
+ if (unlikely(dev->block_cfg_access)) \
+ pci_wait_cfg(dev); \
ret = dev->bus->ops->read(dev->bus, dev->devfn, \
pos, sizeof(type), &data); \
raw_spin_unlock_irq(&pci_lock); \
@@ -172,7 +173,8 @@ int pci_user_write_config_##size \
if (PCI_##size##_BAD) \
return -EINVAL; \
raw_spin_lock_irq(&pci_lock); \
- if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev); \
+ if (unlikely(dev->block_cfg_access)) \
+ pci_wait_cfg(dev); \
ret = dev->bus->ops->write(dev->bus, dev->devfn, \
pos, sizeof(type), val); \
raw_spin_unlock_irq(&pci_lock); \
@@ -401,36 +403,56 @@ int pci_vpd_truncate(struct pci_dev *dev, size_t size)
EXPORT_SYMBOL(pci_vpd_truncate);
/**
- * pci_block_user_cfg_access - Block userspace PCI config reads/writes
+ * pci_cfg_access_lock - Lock PCI config reads/writes
* @dev: pci device struct
*
- * When user access is blocked, any reads or writes to config space will
- * sleep until access is unblocked again. We don't allow nesting of
- * block/unblock calls.
+ * When access is locked, any userspace reads or writes to config
+ * space and concurrent lock requests will sleep until access is
+ * allowed via pci_cfg_access_unlocked again.
*/
-void pci_block_user_cfg_access(struct pci_dev *dev)
+void pci_cfg_access_lock(struct pci_dev *dev)
+{
+ might_sleep();
+
+ raw_spin_lock_irq(&pci_lock);
+ if (dev->block_cfg_access)
+ pci_wait_cfg(dev);
+ dev->block_cfg_access = 1;
+ raw_spin_unlock_irq(&pci_lock);
+}
+EXPORT_SYMBOL_GPL(pci_cfg_access_lock);
+
+/**
+ * pci_cfg_access_trylock - try to lock PCI config reads/writes
+ * @dev: pci device struct
+ *
+ * Same as pci_cfg_access_lock, but will return 0 if access is
+ * already locked, 1 otherwise. This function can be used from
+ * atomic contexts.
+ */
+bool pci_cfg_access_trylock(struct pci_dev *dev)
{
unsigned long flags;
- int was_blocked;
+ bool locked = true;
raw_spin_lock_irqsave(&pci_lock, flags);
- was_blocked = dev->block_ucfg_access;
- dev->block_ucfg_access = 1;
+ if (dev->block_cfg_access)
+ locked = false;
+ else
+ dev->block_cfg_access = 1;
raw_spin_unlock_irqrestore(&pci_lock, flags);
- /* If we BUG() inside the pci_lock, we're guaranteed to hose
- * the machine */
- BUG_ON(was_blocked);
+ return locked;
}
-EXPORT_SYMBOL_GPL(pci_block_user_cfg_access);
+EXPORT_SYMBOL_GPL(pci_cfg_access_trylock);
/**
- * pci_unblock_user_cfg_access - Unblock userspace PCI config reads/writes
+ * pci_cfg_access_unlock - Unlock PCI config reads/writes
* @dev: pci device struct
*
- * This function allows userspace PCI config accesses to resume.
+ * This function allows PCI config accesses to resume.
*/
-void pci_unblock_user_cfg_access(struct pci_dev *dev)
+void pci_cfg_access_unlock(struct pci_dev *dev)
{
unsigned long flags;
@@ -438,10 +460,10 @@ void pci_unblock_user_cfg_access(struct pci_dev *dev)
/* This indicates a problem in the caller, but we don't need
* to kill them, unlike a double-block above. */
- WARN_ON(!dev->block_ucfg_access);
+ WARN_ON(!dev->block_cfg_access);
- dev->block_ucfg_access = 0;
- wake_up_all(&pci_ucfg_wait);
+ dev->block_cfg_access = 0;
+ wake_up_all(&pci_cfg_wait);
raw_spin_unlock_irqrestore(&pci_lock, flags);
}
-EXPORT_SYMBOL_GPL(pci_unblock_user_cfg_access);
+EXPORT_SYMBOL_GPL(pci_cfg_access_unlock);
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index 1969a3ee3058..6a4d70386a3d 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -348,10 +348,10 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
}
iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
- pci_block_user_cfg_access(dev);
+ pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
msleep(100);
- pci_unblock_user_cfg_access(dev);
+ pci_cfg_access_unlock(dev);
iov->initial = initial;
if (nr_virtfn < initial)
@@ -379,10 +379,10 @@ failed:
virtfn_remove(dev, j, 0);
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
- pci_block_user_cfg_access(dev);
+ pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
- pci_unblock_user_cfg_access(dev);
+ pci_cfg_access_unlock(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
@@ -405,10 +405,10 @@ static void sriov_disable(struct pci_dev *dev)
virtfn_remove(dev, i, 0);
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
- pci_block_user_cfg_access(dev);
+ pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
- pci_unblock_user_cfg_access(dev);
+ pci_cfg_access_unlock(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6d4a5319148d..c3cca7cdc6e5 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2965,7 +2965,7 @@ static int pci_dev_reset(struct pci_dev *dev, int probe)
might_sleep();
if (!probe) {
- pci_block_user_cfg_access(dev);
+ pci_cfg_access_lock(dev);
/* block PM suspend, driver probe, etc. */
device_lock(&dev->dev);
}
@@ -2990,7 +2990,7 @@ static int pci_dev_reset(struct pci_dev *dev, int probe)
done:
if (!probe) {
device_unlock(&dev->dev);
- pci_unblock_user_cfg_access(dev);
+ pci_cfg_access_unlock(dev);
}
return rc;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-17 16:14:26 +0000