From e9f5b8145af9a0ee34e98cf01dcd3afb87225538 Mon Sep 17 00:00:00 2001 From: Serban Constantinescu Date: Tue, 5 Mar 2013 15:27:38 +0000 Subject: [PATCH] staging: android: ashmem: Add support for 32bit ashmem calls in a 64bit kernel MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Android's shared memory subsystem, Ashmem, does not support calls from a 32bit userspace in a 64 bit kernel. This patch adds support for syscalls coming from a 32bit userspace in a 64bit kernel. The patch has been successfully tested on ARMv8 AEM(64bit platform model) and Versatile Express A9(32bit platform). v2: Fix missing compat.h include. Signed-off-by: Serban Constantinescu Acked-by: Arve Hjønnevåg Acked-by: John Stultz Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ashmem.c | 21 ++++++++++++++++++++- drivers/staging/android/ashmem.h | 7 +++++++ 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c index 38a9135a2f6d..e681bdd9aa5f 100644 --- a/drivers/staging/android/ashmem.c +++ b/drivers/staging/android/ashmem.c @@ -702,6 +702,23 @@ static long ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return ret; } +/* support of 32bit userspace on 64bit platforms */ +#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 + static const struct file_operations ashmem_fops = { .owner = THIS_MODULE, .open = ashmem_open, @@ -710,7 +727,9 @@ 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 1976b10ef93e..8dc0f0d3adf3 100644 --- a/drivers/staging/android/ashmem.h +++ b/drivers/staging/android/ashmem.h @@ -14,6 +14,7 @@ #include #include +#include #define ASHMEM_NAME_LEN 256 @@ -45,4 +46,10 @@ struct ashmem_pin { #define ASHMEM_GET_PIN_STATUS _IO(__ASHMEMIOC, 9) #define ASHMEM_PURGE_ALL_CACHES _IO(__ASHMEMIOC, 10) +/* support of 32bit userspace on 64bit platforms */ +#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 */ -- 2.39.5