Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934397Ab1ESXzI (ORCPT ); Thu, 19 May 2011 19:55:08 -0400 Received: from na3sys010aog112.obsmtp.com ([74.125.245.92]:46623 "HELO na3sys010aog112.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S934186Ab1ESXzG (ORCPT ); Thu, 19 May 2011 19:55:06 -0400 From: Roland Dreier To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Benjamin Herrenschmidt , Milton Miller , James Bottomley , Hitoshi Mitake , Kashyap Desai , Len Brown , Ravi Anand , Vikas Chaudhary , Matthew Garrett Subject: [PATCH] x86: Remove 32-bit versions of readq()/writeq() Date: Thu, 19 May 2011 16:54:53 -0700 Message-Id: <1305849293-25437-1-git-send-email-roland@kernel.org> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <20110519181500.GF6139@elte.hu> References: <20110519181500.GF6139@elte.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7259 Lines: 257 From: Roland Dreier The presense of a writeq() implementation on 32-bit x86 that splits the 64-bit write into two 32-bit writes turns out to break the mpt2sas driver (and in general is risky for drivers as was discussed in ). To fix this, revert 2c5643b1c5c7 ("x86: provide readq()/writeq() on 32-bit too") and follow-on cleanups. This unfortunately leads to pushing non-atomic definitions of readq() and write() to various x86-only drivers that in the mean time started using the definitions in the x86 version of . However as discussed exhaustively, this is actually the right thing to do, because the right way to split a 64-bit transaction is hardware dependent and therefore belongs in the hardware driver (eg mpt2sas needs a spinlock to make sure no other accesses occur in between the two halves of the access). Build tested on 32- and 64-bit x86 allmodconfig. Link: http://lkml.kernel.org/r/x86-32-writeq-is-broken@mdm.bga.com Cc: Hitoshi Mitake Cc: Kashyap Desai Cc: Len Brown Cc: Ravi Anand Cc: Vikas Chaudhary Cc: Matthew Garrett Signed-off-by: Roland Dreier --- arch/x86/Kconfig | 2 -- arch/x86/include/asm/io.h | 24 ++---------------------- drivers/acpi/apei/einj.c | 8 ++++++++ drivers/acpi/atomicio.c | 4 ++++ drivers/edac/i3200_edac.c | 13 +++++++++++++ drivers/platform/x86/ibm_rtl.c | 13 +++++++++++++ drivers/platform/x86/intel_ips.c | 13 +++++++++++++ drivers/scsi/qla4xxx/ql4_nx.c | 21 +++++++++++++++++++++ 8 files changed, 74 insertions(+), 24 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index cc6c53a..ceb41f3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -16,8 +16,6 @@ config X86_64 config X86 def_bool y select HAVE_AOUT if X86_32 - select HAVE_READQ - select HAVE_WRITEQ select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_IDE select HAVE_OPROFILE diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 0722730..d02804d 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -38,7 +38,6 @@ #include #include -#include #include #include @@ -87,27 +86,6 @@ build_mmio_write(__writel, "l", unsigned int, "r", ) build_mmio_read(readq, "q", unsigned long, "=r", :"memory") build_mmio_write(writeq, "q", unsigned long, "r", :"memory") -#else - -static inline __u64 readq(const volatile void __iomem *addr) -{ - const volatile u32 __iomem *p = addr; - u32 low, high; - - low = readl(p); - high = readl(p + 1); - - return low + ((u64)high << 32); -} - -static inline void writeq(__u64 val, volatile void __iomem *addr) -{ - writel(val, addr); - writel(val >> 32, addr+4); -} - -#endif - #define readq_relaxed(a) readq(a) #define __raw_readq(a) readq(a) @@ -117,6 +95,8 @@ static inline void writeq(__u64 val, volatile void __iomem *addr) #define readq readq #define writeq writeq +#endif + /** * virt_to_phys - map virtual addresses to physical * @address: address to remap diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c index 096aebf..f74b2ea 100644 --- a/drivers/acpi/apei/einj.c +++ b/drivers/acpi/apei/einj.c @@ -101,6 +101,14 @@ static DEFINE_MUTEX(einj_mutex); static struct einj_parameter *einj_param; +#ifndef writeq +static inline void writeq(__u64 val, volatile void __iomem *addr) +{ + writel(val, addr); + writel(val >> 32, addr+4); +} +#endif + static void einj_exec_ctx_init(struct apei_exec_context *ctx) { apei_exec_ctx_init(ctx, einj_ins_type, ARRAY_SIZE(einj_ins_type), diff --git a/drivers/acpi/atomicio.c b/drivers/acpi/atomicio.c index 542e539..7489b89 100644 --- a/drivers/acpi/atomicio.c +++ b/drivers/acpi/atomicio.c @@ -280,9 +280,11 @@ static int acpi_atomic_read_mem(u64 paddr, u64 *val, u32 width) case 32: *val = readl(addr); break; +#ifdef readq case 64: *val = readq(addr); break; +#endif default: return -EINVAL; } @@ -307,9 +309,11 @@ static int acpi_atomic_write_mem(u64 paddr, u64 val, u32 width) case 32: writel(val, addr); break; +#ifdef writeq case 64: writeq(val, addr); break; +#endif default: return -EINVAL; } diff --git a/drivers/edac/i3200_edac.c b/drivers/edac/i3200_edac.c index d41f900..aa08497 100644 --- a/drivers/edac/i3200_edac.c +++ b/drivers/edac/i3200_edac.c @@ -101,6 +101,19 @@ struct i3200_priv { static int nr_channels; +#ifndef readq +static inline __u64 readq(const volatile void __iomem *addr) +{ + const volatile u32 __iomem *p = addr; + u32 low, high; + + low = readl(p); + high = readl(p + 1); + + return low + ((u64)high << 32); +} +#endif + static int how_many_channels(struct pci_dev *pdev) { unsigned char capid0_8b; /* 8th byte of CAPID0 */ diff --git a/drivers/platform/x86/ibm_rtl.c b/drivers/platform/x86/ibm_rtl.c index 94a114a..b1396e5 100644 --- a/drivers/platform/x86/ibm_rtl.c +++ b/drivers/platform/x86/ibm_rtl.c @@ -81,6 +81,19 @@ static void __iomem *rtl_cmd_addr; static u8 rtl_cmd_type; static u8 rtl_cmd_width; +#ifndef readq +static inline __u64 readq(const volatile void __iomem *addr) +{ + const volatile u32 __iomem *p = addr; + u32 low, high; + + low = readl(p); + high = readl(p + 1); + + return low + ((u64)high << 32); +} +#endif + static void __iomem *rtl_port_map(phys_addr_t addr, unsigned long len) { if (rtl_cmd_type == RTL_ADDR_TYPE_MMIO) diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c index 85c8ad4..5ffe7c3 100644 --- a/drivers/platform/x86/intel_ips.c +++ b/drivers/platform/x86/intel_ips.c @@ -344,6 +344,19 @@ struct ips_driver { static bool ips_gpu_turbo_enabled(struct ips_driver *ips); +#ifndef readq +static inline __u64 readq(const volatile void __iomem *addr) +{ + const volatile u32 __iomem *p = addr; + u32 low, high; + + low = readl(p); + high = readl(p + 1); + + return low + ((u64)high << 32); +} +#endif + /** * ips_cpu_busy - is CPU busy? * @ips: IPS driver struct diff --git a/drivers/scsi/qla4xxx/ql4_nx.c b/drivers/scsi/qla4xxx/ql4_nx.c index 35381cb..03e522b 100644 --- a/drivers/scsi/qla4xxx/ql4_nx.c +++ b/drivers/scsi/qla4xxx/ql4_nx.c @@ -655,6 +655,27 @@ static int qla4_8xxx_pci_is_same_window(struct scsi_qla_host *ha, return 0; } +#ifndef readq +static inline __u64 readq(const volatile void __iomem *addr) +{ + const volatile u32 __iomem *p = addr; + u32 low, high; + + low = readl(p); + high = readl(p + 1); + + return low + ((u64)high << 32); +} +#endif + +#ifndef writeq +static inline void writeq(__u64 val, volatile void __iomem *addr) +{ + writel(val, addr); + writel(val >> 32, addr+4); +} +#endif + static int qla4_8xxx_pci_mem_read_direct(struct scsi_qla_host *ha, u64 off, void *data, int size) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/