From e06c43bbcb4638c9629d48769d6032c853a60f2b Mon Sep 17 00:00:00 2001 From: Serban Constantinescu Date: Fri, 18 Jan 2013 17:42:15 +0000 Subject: staging: android: ashmem: Add support for 32bit ashmem calls in a 64bit kernel Android's shared memory subsystem, Ashmem, does not support calls from a 32-bit userspace in a 64 bit kernel. This patch adds support for syscalls coming from a 32-bit userspace in a 64-bit kernel. The patch has been successfully tested on ARMv8 AEM and Versatile Express V2P-CA9. Signed-off-by: Serban Constantinescu --- drivers/staging/android/ashmem.c | 20 +++++++++++++++++++- drivers/staging/android/ashmem.h | 6 ++++++ 2 files changed, 25 insertions(+), 1 deletion(-) diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c index 19ecf864c6d..64967e2b43e 100644 --- a/drivers/staging/android/ashmem.c +++ b/drivers/staging/android/ashmem.c @@ -692,6 +692,22 @@ static long ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return ret; } +/* support for 32bit syscalls on 64bit systems */ +#ifdef CONFIG_COMPAT +static long compat_ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case COMPAT_ASHMEM_SET_SIZE: + cmd = ASHMEM_SET_SIZE; + break; + case COMPAT_ASHMEM_SET_PROT_MASK: + cmd = ASHMEM_SET_PROT_MASK; + break; + } + return ashmem_ioctl(file, cmd, arg); +} +#endif /* CONFIG_COMPAT */ + static const struct file_operations ashmem_fops = { .owner = THIS_MODULE, .open = ashmem_open, @@ -700,7 +716,9 @@ static const struct file_operations ashmem_fops = { .llseek = ashmem_llseek, .mmap = ashmem_mmap, .unlocked_ioctl = ashmem_ioctl, - .compat_ioctl = ashmem_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = compat_ashmem_ioctl, +#endif }; static struct miscdevice ashmem_misc = { diff --git a/drivers/staging/android/ashmem.h b/drivers/staging/android/ashmem.h index 4ecdc731d2f..0ca56c0a927 100644 --- a/drivers/staging/android/ashmem.h +++ b/drivers/staging/android/ashmem.h @@ -47,4 +47,10 @@ struct ashmem_pin { #define ASHMEM_GET_PIN_STATUS _IO(__ASHMEMIOC, 9) #define ASHMEM_PURGE_ALL_CACHES _IO(__ASHMEMIOC, 10) +/* support for 32bit syscalls on 64bit systems */ +#ifdef CONFIG_COMPAT +#define COMPAT_ASHMEM_SET_SIZE _IOW(__ASHMEMIOC, 3, compat_size_t) +#define COMPAT_ASHMEM_SET_PROT_MASK _IOW(__ASHMEMIOC, 5, unsigned int) +#endif + #endif /* _LINUX_ASHMEM_H */ -- cgit v1.2.3