diff options
| -rw-r--r-- | drivers/pci/access.c | 74 | ||||
| -rw-r--r-- | drivers/pci/iov.c | 12 | ||||
| -rw-r--r-- | drivers/pci/pci.c | 4 | ||||
| -rw-r--r-- | drivers/scsi/ipr.c | 67 | ||||
| -rw-r--r-- | drivers/scsi/ipr.h | 1 | ||||
| -rw-r--r-- | drivers/uio/uio_pci_generic.c | 9 | ||||
| -rw-r--r-- | include/linux/pci.h | 14 |
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) |