From f18793b096e69c7acfce66cded483ba9fc01762a Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Thu, 14 Jun 2018 17:44:31 +0100 Subject: compiler: add a sizeof_field() macro Determining the size of a field is useful when you don't have a struct variable handy. Open-coding this is ugly. This patch adds the sizeof_field() macro, which is similar to typeof_field(). Existing instances are updated to use the macro. Signed-off-by: Stefan Hajnoczi Reviewed-by: John Snow Message-id: 20180614164431.29305-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi --- include/hw/xen/io/ring.h | 2 +- include/qemu/compiler.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h index abbca47..ffa3eba 100644 --- a/include/hw/xen/io/ring.h +++ b/include/hw/xen/io/ring.h @@ -65,7 +65,7 @@ typedef unsigned int RING_IDX; */ #define __CONST_RING_SIZE(_s, _sz) \ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \ - sizeof(((struct _s##_sring *)0)->ring[0]))) + sizeof_field(struct _s##_sring, ring[0]))) /* * The same for passing in an actual pointer instead of a name tag. */ diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h index 9f76269..5843812 100644 --- a/include/qemu/compiler.h +++ b/include/qemu/compiler.h @@ -64,6 +64,8 @@ (type *) ((char *) __mptr - offsetof(type, member));}) #endif +#define sizeof_field(type, field) sizeof(((type *)0)->field) + /* Convert from a base type to a parent type, with compile time checking. */ #ifdef __GNUC__ #define DO_UPCAST(type, field, dev) ( __extension__ ( { \ -- cgit v1.1 From ed6e2161715c527330f936d44af4c547f25f687e Mon Sep 17 00:00:00 2001 From: Nishanth Aravamudan Date: Fri, 22 Jun 2018 12:37:00 -0700 Subject: linux-aio: properly bubble up errors from initialization laio_init() can fail for a couple of reasons, which will lead to a NULL pointer dereference in laio_attach_aio_context(). To solve this, add a aio_setup_linux_aio() function which is called early in raw_open_common. If this fails, propagate the error up. The signature of aio_get_linux_aio() was not modified, because it seems preferable to return the actual errno from the possible failing initialization calls. Additionally, when the AioContext changes, we need to associate a LinuxAioState with the new AioContext. Use the bdrv_attach_aio_context callback and call the new aio_setup_linux_aio(), which will allocate a new AioContext if needed, and return errors on failures. If it fails for any reason, fallback to threaded AIO with an error message, as the device is already in-use by the guest. Add an assert that aio_get_linux_aio() cannot return NULL. Signed-off-by: Nishanth Aravamudan Message-id: 20180622193700.6523-1-naravamudan@digitalocean.com Signed-off-by: Stefan Hajnoczi --- include/block/aio.h | 3 +++ include/block/raw-aio.h | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/block/aio.h b/include/block/aio.h index ae6f354..f08630c 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -381,6 +381,9 @@ GSource *aio_get_g_source(AioContext *ctx); /* Return the ThreadPool bound to this AioContext */ struct ThreadPool *aio_get_thread_pool(AioContext *ctx); +/* Setup the LinuxAioState bound to this AioContext */ +struct LinuxAioState *aio_setup_linux_aio(AioContext *ctx, Error **errp); + /* Return the LinuxAioState bound to this AioContext */ struct LinuxAioState *aio_get_linux_aio(AioContext *ctx); diff --git a/include/block/raw-aio.h b/include/block/raw-aio.h index 0e717fd..8d698cc 100644 --- a/include/block/raw-aio.h +++ b/include/block/raw-aio.h @@ -43,7 +43,7 @@ /* linux-aio.c - Linux native implementation */ #ifdef CONFIG_LINUX_AIO typedef struct LinuxAioState LinuxAioState; -LinuxAioState *laio_init(void); +LinuxAioState *laio_init(Error **errp); void laio_cleanup(LinuxAioState *s); int coroutine_fn laio_co_submit(BlockDriverState *bs, LinuxAioState *s, int fd, uint64_t offset, QEMUIOVector *qiov, int type); -- cgit v1.1