From c748814b20f1f1b43eed1fd32c84579c60f4cc58 Mon Sep 17 00:00:00 2001 From: Pierre Morel Date: Thu, 30 Nov 2017 13:55:24 +0100 Subject: s390x/pci: factor out endianess conversion 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 Message-Id: <1512046530-17773-2-git-send-email-pmorel@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck --- hw/s390x/s390-pci-inst.c | 58 ++++++++++++++++++++++++++---------------------- 1 file changed, 32 insertions(+), 26 deletions(-) (limited to 'hw') diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c index 6f41083244..cb84d209e0 100644 --- a/hw/s390x/s390-pci-inst.c +++ b/hw/s390x/s390-pci-inst.c @@ -318,6 +318,36 @@ 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, uintptr_t ra) { CPUS390XState *env = &cpu->env; @@ -389,19 +419,7 @@ int pcilg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra) 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)) { s390_program_interrupt(env, PGM_OPERAND, 4, ra); return 0; } @@ -504,19 +522,7 @@ int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra) s390_program_interrupt(env, PGM_OPERAND, 4, ra); 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)) { s390_program_interrupt(env, PGM_OPERAND, 4, ra); return 0; } -- cgit v1.2.1