From 810033be083040591fee2fc09f2f294670ed1930 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marc-Andr=C3=A9=20Lureau?= Date: Wed, 25 Nov 2020 14:06:34 +0400 Subject: [PATCH] libvhost-user: replace qemu/memfd.h usage MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Undo the damage from commit 5f9ff1eff3 ("libvhost-user: Support tracking inflight I/O in shared memory") which introduced glib dependency through osdep.h inclusion. libvhost-user.c tries to stay free from glib usage. Use glibc memfd_create directly when available (assumed so when MFD_ALLOW_SEALING is defined). A following commit will make the project standalone and check for memfd API at configure time, instead of a panic at runtime. Signed-off-by: Marc-André Lureau Reviewed-by: Stefan Hajnoczi Message-Id: <20201125100640.366523-3-marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- contrib/libvhost-user/libvhost-user.c | 50 ++++++++++++++++++++++++++++++----- 1 file changed, 43 insertions(+), 7 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index 1c1cfbf1e7..54aabd1878 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -42,8 +42,6 @@ #endif #include "qemu/atomic.h" -#include "qemu/osdep.h" -#include "qemu/memfd.h" #include "libvhost-user.h" @@ -1615,11 +1613,45 @@ vu_inflight_queue_size(uint16_t queue_size) sizeof(uint16_t), INFLIGHT_ALIGNMENT); } +#ifdef MFD_ALLOW_SEALING +static void * +memfd_alloc(const char *name, size_t size, unsigned int flags, int *fd) +{ + void *ptr; + int ret; + + *fd = memfd_create(name, MFD_ALLOW_SEALING); + if (*fd < 0) { + return NULL; + } + + ret = ftruncate(*fd, size); + if (ret < 0) { + close(*fd); + return NULL; + } + + ret = fcntl(*fd, F_ADD_SEALS, flags); + if (ret < 0) { + close(*fd); + return NULL; + } + + ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, *fd, 0); + if (ptr == MAP_FAILED) { + close(*fd); + return NULL; + } + + return ptr; +} +#endif + static bool vu_get_inflight_fd(VuDev *dev, VhostUserMsg *vmsg) { - int fd; - void *addr; + int fd = -1; + void *addr = NULL; uint64_t mmap_size; uint16_t num_queues, queue_size; @@ -1637,9 +1669,13 @@ vu_get_inflight_fd(VuDev *dev, VhostUserMsg *vmsg) mmap_size = vu_inflight_queue_size(queue_size) * num_queues; - addr = qemu_memfd_alloc("vhost-inflight", mmap_size, - F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, - &fd, NULL); +#ifdef MFD_ALLOW_SEALING + addr = memfd_alloc("vhost-inflight", mmap_size, + F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, + &fd); +#else + vu_panic(dev, "Not implemented: memfd support is missing"); +#endif if (!addr) { vu_panic(dev, "Failed to alloc vhost inflight area"); -- 2.11.0