From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44355) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zej2G-0001Jz-15 for qemu-devel@nongnu.org; Wed, 23 Sep 2015 08:20:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zej2C-0005EV-AN for qemu-devel@nongnu.org; Wed, 23 Sep 2015 08:20:31 -0400 Received: from lhrrgout.huawei.com ([194.213.3.17]:59109) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zej2C-0005E6-2X for qemu-devel@nongnu.org; Wed, 23 Sep 2015 08:20:28 -0400 References: <1442333283-13119-1-git-send-email-marcandre.lureau@redhat.com> <1442333283-13119-42-git-send-email-marcandre.lureau@redhat.com> <56016774.4040703@huawei.com> <999019625.15207582.1442933948058.JavaMail.zimbra@redhat.com> From: Claudio Fontana Message-ID: <56029904.8000101@huawei.com> Date: Wed, 23 Sep 2015 14:20:20 +0200 MIME-Version: 1.0 In-Reply-To: <999019625.15207582.1442933948058.JavaMail.zimbra@redhat.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH v3 41/46] ivshmem: do not keep shm_fd open List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= Cc: marcandre lureau , drjones@redhat.com, cam@cs.ualberta.ca, qemu-devel@nongnu.org, stefanha@redhat.com On 22.09.2015 16:59, Marc-André Lureau wrote: > Hi > > ----- Original Message ----- >> On 15.09.2015 18:07, marcandre.lureau@redhat.com wrote: >>> From: Marc-André Lureau >>> >>> Remove shm_fd from device state, closing it as early as possible to avoid >>> leaks. >>> >>> Signed-off-by: Marc-André Lureau >>> --- >>> hw/misc/ivshmem.c | 14 +++++--------- >>> 1 file changed, 5 insertions(+), 9 deletions(-) >>> >>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >>> index 4adcac5..f9ac955 100644 >>> --- a/hw/misc/ivshmem.c >>> +++ b/hw/misc/ivshmem.c >>> @@ -88,7 +88,6 @@ typedef struct IVShmemState { >>> MemoryRegion ivshmem; >>> uint64_t ivshmem_size; /* size of shared memory region */ >>> uint32_t ivshmem_64bit; >>> - int shm_fd; /* shared memory file descriptor */ >> >> is it in no way useful during debugging to have access to this field? >> Or is it easily available elsewhere? > > How would it be useful during debugging? Once the memory is mapped there isn't much you can do with it, it's just keeping a fd open, isn't it? all right. > >> >> Ciao C. >> >>> >>> Peer *peers; >>> int nb_peers; /* how many peers we have space for */ >>> @@ -235,7 +234,7 @@ static uint64_t ivshmem_io_read(void *opaque, hwaddr >>> addr, >>> >>> case IVPOSITION: >>> /* return my VM ID if the memory is mapped */ >>> - if (s->shm_fd >= 0) { >>> + if (memory_region_is_mapped(&s->ivshmem)) { >>> ret = s->vm_id; >>> } else { >>> ret = -1; >>> @@ -356,8 +355,6 @@ static int create_shared_memory_BAR(IVShmemState *s, >>> int fd, uint8_t attr, >>> return -1; >>> } >>> >>> - s->shm_fd = fd; >>> - >>> memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s), "ivshmem.bar2", >>> s->ivshmem_size, ptr); >>> vmstate_register_ram(&s->ivshmem, DEVICE(s)); >>> @@ -535,7 +532,7 @@ static void ivshmem_read(void *opaque, const uint8_t >>> *buf, int size) >>> if (incoming_posn == -1) { >>> void * map_ptr; >>> >>> - if (s->shm_fd >= 0) { >>> + if (memory_region_is_mapped(&s->ivshmem)) { >>> error_report("shm already initialized"); >>> close(incoming_fd); >>> return; >>> @@ -564,9 +561,7 @@ static void ivshmem_read(void *opaque, const uint8_t >>> *buf, int size) >>> >>> memory_region_add_subregion(&s->bar, 0, &s->ivshmem); >>> >>> - /* only store the fd if it is successfully mapped */ >>> - s->shm_fd = incoming_fd; >>> - >>> + close(incoming_fd); >>> return; >>> } >>> >>> @@ -827,6 +822,7 @@ static void pci_ivshmem_realize(PCIDevice *dev, Error >>> **errp) >>> } >>> >>> create_shared_memory_BAR(s, fd, attr, errp); >>> + close(fd); >>> } >>> } >>> >>> @@ -842,7 +838,7 @@ static void pci_ivshmem_exit(PCIDevice *dev) >>> error_free(s->migration_blocker); >>> } >>> >>> - if (s->shm_fd >= 0) { >>> + if (memory_region_is_mapped(&s->ivshmem)) { >>> void *addr = memory_region_get_ram_ptr(&s->ivshmem); >>> >>> vmstate_unregister_ram(&s->ivshmem, DEVICE(dev)); >>>