From e04b0ea2e0f9c1bb0d874db4493fc7f7a623116b Mon Sep 17 00:00:00 2001 From: Brian King Date: Tue, 27 Sep 2005 01:21:55 -0700 Subject: [PATCH] PCI: Block config access during BIST Some PCI adapters (eg. ipr scsi adapters) have an exposure today in that they issue BIST to the adapter to reset the card. If, during the time it takes to complete BIST, userspace attempts to access PCI config space, the host bus bridge will master abort the access since the ipr adapter does not respond on the PCI bus for a brief period of time when running BIST. On PPC64 hardware, this master abort results in the host PCI bridge isolating that PCI device from the rest of the system, making the device unusable until Linux is rebooted. This patch is an attempt to close that exposure by introducing some blocking code in the PCI code. When blocked, writes will be humored and reads will return the cached value. Ben Herrenschmidt has also mentioned that he plans to use this in PPC power management. Signed-off-by: Brian King Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman drivers/pci/access.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/pci-sysfs.c | 20 +++++----- drivers/pci/pci.h | 7 +++ drivers/pci/proc.c | 28 +++++++-------- drivers/pci/syscall.c | 14 +++---- include/linux/pci.h | 7 +++ 6 files changed, 134 insertions(+), 31 deletions(-) --- drivers/pci/syscall.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/pci/syscall.c') diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c index c071790cc983..87fafc08cb9d 100644 --- a/drivers/pci/syscall.c +++ b/drivers/pci/syscall.c @@ -13,7 +13,7 @@ #include #include #include - +#include "pci.h" asmlinkage long sys_pciconfig_read(unsigned long bus, unsigned long dfn, @@ -38,13 +38,13 @@ sys_pciconfig_read(unsigned long bus, unsigned long dfn, lock_kernel(); switch (len) { case 1: - cfg_ret = pci_read_config_byte(dev, off, &byte); + cfg_ret = pci_user_read_config_byte(dev, off, &byte); break; case 2: - cfg_ret = pci_read_config_word(dev, off, &word); + cfg_ret = pci_user_read_config_word(dev, off, &word); break; case 4: - cfg_ret = pci_read_config_dword(dev, off, &dword); + cfg_ret = pci_user_read_config_dword(dev, off, &dword); break; default: err = -EINVAL; @@ -112,7 +112,7 @@ sys_pciconfig_write(unsigned long bus, unsigned long dfn, err = get_user(byte, (u8 __user *)buf); if (err) break; - err = pci_write_config_byte(dev, off, byte); + err = pci_user_write_config_byte(dev, off, byte); if (err != PCIBIOS_SUCCESSFUL) err = -EIO; break; @@ -121,7 +121,7 @@ sys_pciconfig_write(unsigned long bus, unsigned long dfn, err = get_user(word, (u16 __user *)buf); if (err) break; - err = pci_write_config_word(dev, off, word); + err = pci_user_write_config_word(dev, off, word); if (err != PCIBIOS_SUCCESSFUL) err = -EIO; break; @@ -130,7 +130,7 @@ sys_pciconfig_write(unsigned long bus, unsigned long dfn, err = get_user(dword, (u32 __user *)buf); if (err) break; - err = pci_write_config_dword(dev, off, dword); + err = pci_user_write_config_dword(dev, off, dword); if (err != PCIBIOS_SUCCESSFUL) err = -EIO; break; -- cgit v1.2.3