From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53109) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eKONT-0007rP-V6 for qemu-devel@nongnu.org; Thu, 30 Nov 2017 07:55:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eKONQ-0003m0-RW for qemu-devel@nongnu.org; Thu, 30 Nov 2017 07:55:44 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52392) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eKONQ-0003lZ-JA for qemu-devel@nongnu.org; Thu, 30 Nov 2017 07:55:40 -0500 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vAUCs9VP059633 for ; Thu, 30 Nov 2017 07:55:37 -0500 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ejhut1jt4-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 30 Nov 2017 07:55:37 -0500 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 30 Nov 2017 12:55:34 -0000 From: Pierre Morel Date: Thu, 30 Nov 2017 13:55:24 +0100 In-Reply-To: <1512046530-17773-1-git-send-email-pmorel@linux.vnet.ibm.com> References: <1512046530-17773-1-git-send-email-pmorel@linux.vnet.ibm.com> Message-Id: <1512046530-17773-2-git-send-email-pmorel@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH v4 1/7] s390x/pci: factor out endianess conversion List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: cohuck@redhat.com, agraf@suse.de, borntraeger@de.ibm.com, zyimin@linux.vnet.ibm.com, mst@redhat.com, thuth@redhat.com, pasic@linux.vnet.ibm.com There are two places where the same endianness conversion is done. Let's factor this out into a static function. Note that the conversion must always be done for data in a register: The S390 BE guest converted date to le before issuing the instruction. After interception in a BE host: ZPCI VFIO using pwrite must make the conversion back for the BE kernel. Kernel will do BE to le translation when loading the register for the real instruction. After interception in a le host: TCG stores a BE register in le, swapping bytes. But since the data in the register was already le it is now BE ZPCI VFIO must convert it to le before writing to the PCI memory. In both cases ZPCI VFIO must swap the bytes from the register. Signed-off-by: Pierre Morel Reviewed-by: Yi Min Zhao --- hw/s390x/s390-pci-inst.c | 59 +++++++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 26 deletions(-) diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c index 8e088f3..3e1f1a0 100644 --- a/hw/s390x/s390-pci-inst.c +++ b/hw/s390x/s390-pci-inst.c @@ -314,6 +314,36 @@ out: return 0; } +/** + * Swap data contained in s390x big endian registers to little endian + * PCI bars. + * + * @ptr: a pointer to a uint64_t data field + * @len: the length of the valid data, must be 1,2,4 or 8 + */ +static int zpci_endian_swap(uint64_t *ptr, uint8_t len) +{ + uint64_t data = *ptr; + + switch (len) { + case 1: + break; + case 2: + data = bswap16(data); + break; + case 4: + data = bswap32(data); + break; + case 8: + data = bswap64(data); + break; + default: + return -EINVAL; + } + *ptr = data; + return 0; +} + int pcilg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2) { CPUS390XState *env = &cpu->env; @@ -385,19 +415,7 @@ int pcilg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2) data = pci_host_config_read_common( pbdev->pdev, offset, pci_config_size(pbdev->pdev), len); - switch (len) { - case 1: - break; - case 2: - data = bswap16(data); - break; - case 4: - data = bswap32(data); - break; - case 8: - data = bswap64(data); - break; - default: + if (zpci_endian_swap(&data, len)) { program_interrupt(env, PGM_OPERAND, 4); return 0; } @@ -500,19 +518,8 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2) program_interrupt(env, PGM_OPERAND, 4); return 0; } - switch (len) { - case 1: - break; - case 2: - data = bswap16(data); - break; - case 4: - data = bswap32(data); - break; - case 8: - data = bswap64(data); - break; - default: + + if (zpci_endian_swap(&data, len)) { program_interrupt(env, PGM_OPERAND, 4); return 0; } -- 2.7.4