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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
-rw-r--r--drivers/scsi/ipr.c67
-rw-r--r--drivers/scsi/ipr.h1
-rw-r--r--drivers/uio/uio_pci_generic.c9
-rw-r--r--include/linux/pci.h14
7 files changed, 131 insertions, 50 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;
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index fd860d952b28..67b169b7a5be 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -7638,8 +7638,12 @@ static int ipr_reset_restore_cfg_space(struct ipr_cmnd *ipr_cmd)
**/
static int ipr_reset_bist_done(struct ipr_cmnd *ipr_cmd)
{
+ struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
+
ENTER;
- pci_unblock_user_cfg_access(ipr_cmd->ioa_cfg->pdev);
+ if (ioa_cfg->cfg_locked)
+ pci_cfg_access_unlock(ioa_cfg->pdev);
+ ioa_cfg->cfg_locked = 0;
ipr_cmd->job_step = ipr_reset_restore_cfg_space;
LEAVE;
return IPR_RC_JOB_CONTINUE;
@@ -7660,8 +7664,6 @@ static int ipr_reset_start_bist(struct ipr_cmnd *ipr_cmd)
int rc = PCIBIOS_SUCCESSFUL;
ENTER;
- pci_block_user_cfg_access(ioa_cfg->pdev);
-
if (ioa_cfg->ipr_chip->bist_method == IPR_MMIO)
writel(IPR_UPROCI_SIS64_START_BIST,
ioa_cfg->regs.set_uproc_interrupt_reg32);
@@ -7673,7 +7675,9 @@ static int ipr_reset_start_bist(struct ipr_cmnd *ipr_cmd)
ipr_reset_start_timer(ipr_cmd, IPR_WAIT_FOR_BIST_TIMEOUT);
rc = IPR_RC_JOB_RETURN;
} else {
- pci_unblock_user_cfg_access(ipr_cmd->ioa_cfg->pdev);
+ if (ioa_cfg->cfg_locked)
+ pci_cfg_access_unlock(ipr_cmd->ioa_cfg->pdev);
+ ioa_cfg->cfg_locked = 0;
ipr_cmd->s.ioasa.hdr.ioasc = cpu_to_be32(IPR_IOASC_PCI_ACCESS_ERROR);
rc = IPR_RC_JOB_CONTINUE;
}
@@ -7716,7 +7720,6 @@ static int ipr_reset_slot_reset(struct ipr_cmnd *ipr_cmd)
struct pci_dev *pdev = ioa_cfg->pdev;
ENTER;
- pci_block_user_cfg_access(pdev);
pci_set_pcie_reset_state(pdev, pcie_warm_reset);
ipr_cmd->job_step = ipr_reset_slot_reset_done;
ipr_reset_start_timer(ipr_cmd, IPR_PCI_RESET_TIMEOUT);
@@ -7725,6 +7728,56 @@ static int ipr_reset_slot_reset(struct ipr_cmnd *ipr_cmd)
}
/**
+ * ipr_reset_block_config_access_wait - Wait for permission to block config access
+ * @ipr_cmd: ipr command struct
+ *
+ * Description: This attempts to block config access to the IOA.
+ *
+ * Return value:
+ * IPR_RC_JOB_CONTINUE / IPR_RC_JOB_RETURN
+ **/
+static int ipr_reset_block_config_access_wait(struct ipr_cmnd *ipr_cmd)
+{
+ struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
+ int rc = IPR_RC_JOB_CONTINUE;
+
+ if (pci_cfg_access_trylock(ioa_cfg->pdev)) {
+ ioa_cfg->cfg_locked = 1;
+ ipr_cmd->job_step = ioa_cfg->reset;
+ } else {
+ if (ipr_cmd->u.time_left) {
+ rc = IPR_RC_JOB_RETURN;
+ ipr_cmd->u.time_left -= IPR_CHECK_FOR_RESET_TIMEOUT;
+ ipr_reset_start_timer(ipr_cmd,
+ IPR_CHECK_FOR_RESET_TIMEOUT);
+ } else {
+ ipr_cmd->job_step = ioa_cfg->reset;
+ dev_err(&ioa_cfg->pdev->dev,
+ "Timed out waiting to lock config access. Resetting anyway.\n");
+ }
+ }
+
+ return rc;
+}
+
+/**
+ * ipr_reset_block_config_access - Block config access to the IOA
+ * @ipr_cmd: ipr command struct
+ *
+ * Description: This attempts to block config access to the IOA
+ *
+ * Return value:
+ * IPR_RC_JOB_CONTINUE
+ **/
+static int ipr_reset_block_config_access(struct ipr_cmnd *ipr_cmd)
+{
+ ipr_cmd->ioa_cfg->cfg_locked = 0;
+ ipr_cmd->job_step = ipr_reset_block_config_access_wait;
+ ipr_cmd->u.time_left = IPR_WAIT_FOR_RESET_TIMEOUT;
+ return IPR_RC_JOB_CONTINUE;
+}
+
+/**
* ipr_reset_allowed - Query whether or not IOA can be reset
* @ioa_cfg: ioa config struct
*
@@ -7763,7 +7816,7 @@ static int ipr_reset_wait_to_start_bist(struct ipr_cmnd *ipr_cmd)
ipr_cmd->u.time_left -= IPR_CHECK_FOR_RESET_TIMEOUT;
ipr_reset_start_timer(ipr_cmd, IPR_CHECK_FOR_RESET_TIMEOUT);
} else {
- ipr_cmd->job_step = ioa_cfg->reset;
+ ipr_cmd->job_step = ipr_reset_block_config_access;
rc = IPR_RC_JOB_CONTINUE;
}
@@ -7796,7 +7849,7 @@ static int ipr_reset_alert(struct ipr_cmnd *ipr_cmd)
writel(IPR_UPROCI_RESET_ALERT, ioa_cfg->regs.set_uproc_interrupt_reg32);
ipr_cmd->job_step = ipr_reset_wait_to_start_bist;
} else {
- ipr_cmd->job_step = ioa_cfg->reset;
+ ipr_cmd->job_step = ipr_reset_block_config_access;
}
ipr_cmd->u.time_left = IPR_WAIT_FOR_RESET_TIMEOUT;
diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index ac84736c1b9c..b13f9cc12279 100644
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -1387,6 +1387,7 @@ struct ipr_ioa_cfg {
u8 msi_received:1;
u8 sis64:1;
u8 dump_timeout:1;
+ u8 cfg_locked:1;
u8 revid;
diff --git a/drivers/uio/uio_pci_generic.c b/drivers/uio/uio_pci_generic.c
index 02bd47bdee1c..56d00c6258f0 100644
--- a/drivers/uio/uio_pci_generic.c
+++ b/drivers/uio/uio_pci_generic.c
@@ -55,7 +55,8 @@ static irqreturn_t irqhandler(int irq, struct uio_info *info)
BUILD_BUG_ON(PCI_COMMAND % 4);
BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
- pci_block_user_cfg_access(pdev);
+ if (!pci_cfg_access_trylock(pdev))
+ goto error;
/* Read both command and status registers in a single 32-bit operation.
* Note: we could cache the value for command and move the status read
@@ -79,7 +80,7 @@ static irqreturn_t irqhandler(int irq, struct uio_info *info)
ret = IRQ_HANDLED;
done:
- pci_unblock_user_cfg_access(pdev);
+ pci_cfg_access_lock(pdev);
return ret;
}
@@ -91,7 +92,7 @@ static int __devinit verify_pci_2_3(struct pci_dev *pdev)
u16 orig, new;
int err = 0;
- pci_block_user_cfg_access(pdev);
+ pci_cfg_access_lock(pdev);
pci_read_config_word(pdev, PCI_COMMAND, &orig);
pci_write_config_word(pdev, PCI_COMMAND,
orig ^ PCI_COMMAND_INTX_DISABLE);
@@ -114,7 +115,7 @@ static int __devinit verify_pci_2_3(struct pci_dev *pdev)
/* Now restore the original value. */
pci_write_config_word(pdev, PCI_COMMAND, orig);
err:
- pci_unblock_user_cfg_access(pdev);
+ pci_cfg_access_unlock(pdev);
return err;
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 84225c756bd1..72401596b2a8 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -308,7 +308,7 @@ struct pci_dev {
unsigned int is_added:1;
unsigned int is_busmaster:1; /* device is busmaster */
unsigned int no_msi:1; /* device may not use msi */
- unsigned int block_ucfg_access:1; /* userspace config space access is blocked */
+ unsigned int block_cfg_access:1; /* config space access is blocked */
unsigned int broken_parity_status:1; /* Device generates false positive parity */
unsigned int irq_reroute_variant:2; /* device needs IRQ rerouting variant */
unsigned int msi_enabled:1;
@@ -1085,8 +1085,9 @@ int ht_create_irq(struct pci_dev *dev, int idx);
void ht_destroy_irq(unsigned int irq);
#endif /* CONFIG_HT_IRQ */
-extern void pci_block_user_cfg_access(struct pci_dev *dev);
-extern void pci_unblock_user_cfg_access(struct pci_dev *dev);
+extern void pci_cfg_access_lock(struct pci_dev *dev);
+extern bool pci_cfg_access_trylock(struct pci_dev *dev);
+extern void pci_cfg_access_unlock(struct pci_dev *dev);
/*
* PCI domain support. Sometimes called PCI segment (eg by ACPI),
@@ -1283,10 +1284,13 @@ static inline void pci_release_regions(struct pci_dev *dev)
#define pci_dma_burst_advice(pdev, strat, strategy_parameter) do { } while (0)
-static inline void pci_block_user_cfg_access(struct pci_dev *dev)
+static inline void pci_block_cfg_access(struct pci_dev *dev)
{ }
-static inline void pci_unblock_user_cfg_access(struct pci_dev *dev)
+static inline int pci_block_cfg_access_in_atomic(struct pci_dev *dev)
+{ return 0; }
+
+static inline void pci_unblock_cfg_access(struct pci_dev *dev)
{ }
static inline struct pci_bus *pci_find_next_bus(const struct pci_bus *from)