From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47558) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3fpt-0003x3-CN for qemu-devel@nongnu.org; Thu, 27 Apr 2017 05:35:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d3fps-0004Np-44 for qemu-devel@nongnu.org; Thu, 27 Apr 2017 05:35:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42780) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d3fpr-0004MV-Rl for qemu-devel@nongnu.org; Thu, 27 Apr 2017 05:35:40 -0400 From: Peter Xu Date: Thu, 27 Apr 2017 17:34:18 +0800 Message-Id: <1493285660-4470-7-git-send-email-peterx@redhat.com> In-Reply-To: <1493285660-4470-1-git-send-email-peterx@redhat.com> References: <1493285660-4470-1-git-send-email-peterx@redhat.com> Subject: [Qemu-devel] [RFC PATCH 6/8] memory: introduce AddressSpaceOps List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: tianyu.lan@intel.com, Paolo Bonzini , kevin.tian@intel.com, yi.l.liu@intel.com, peterx@redhat.com, Jason Wang , David Gibson , Alex Williamson This is something similar to MemoryRegionOps, it's just for address spaces to store arch-specific hooks. The first hook I would like to introduce is iommu_get(). For systems that have IOMMUs, we will create a special address space per device which is different from system default address space for it (please refer to pci_device_iommu_address_space()). Normally when that happens, there will be one specific IOMMU (or say, translation unit) stands right behind that new address space. This iommu_get() fetches that guy behind the address space. Here, the guy is defined as IOMMUObject, which is currently a (void *). In the future, maybe we can make it a better definition, but imho it's good enough for now, considering it's arch-dependent. Signed-off-by: Peter Xu --- include/exec/memory.h | 30 ++++++++++++++++++++++++++++++ memory.c | 8 ++++++++ 2 files changed, 38 insertions(+) diff --git a/include/exec/memory.h b/include/exec/memory.h index e5707b3..0b0b58b 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -183,6 +183,15 @@ struct MemoryRegionOps { const MemoryRegionMmio old_mmio; }; +/* + * This stands for an IOMMU unit. Normally it should be exactly the + * IOMMU device, however this can also be actually anything which is + * related to that translation unit. What it is should be totally + * arch-dependent. Maybe one day we can have something better than a + * (void *) here. + */ +typedef void *IOMMUObject; + typedef struct MemoryRegionIOMMUOps MemoryRegionIOMMUOps; struct MemoryRegionIOMMUOps { @@ -282,6 +291,19 @@ struct MemoryListener { }; /** + * AddressSpaceOps: callbacks structure for address space specific operations + * + * @iommu_get: returns an IOMMU object that backs the address space. + * Normally this should be NULL for generic address + * spaces, and it's only used when there is one + * translation unit behind this address space. + */ +struct AddressSpaceOps { + IOMMUObject *(*iommu_get)(AddressSpace *as); +}; +typedef struct AddressSpaceOps AddressSpaceOps; + +/** * AddressSpace: describes a mapping of addresses to #MemoryRegion objects */ struct AddressSpace { @@ -302,6 +324,7 @@ struct AddressSpace { MemoryListener dispatch_listener; QTAILQ_HEAD(memory_listeners_as, MemoryListener) listeners; QTAILQ_ENTRY(AddressSpace) address_spaces_link; + AddressSpaceOps as_ops; }; /** @@ -1800,6 +1823,13 @@ address_space_write_cached(MemoryRegionCache *cache, hwaddr addr, address_space_write(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len); } +/** + * address_space_iommu_get: Get the backend IOMMU for the address space + * + * @as: the address space to fetch IOMMU from + */ +IOMMUObject *address_space_iommu_get(AddressSpace *as); + #endif #endif diff --git a/memory.c b/memory.c index 6af523e..6aaad45 100644 --- a/memory.c +++ b/memory.c @@ -2500,6 +2500,14 @@ void address_space_destroy(AddressSpace *as) call_rcu(as, do_address_space_destroy, rcu); } +IOMMUObject *address_space_iommu_get(AddressSpace *as) +{ + if (!as->as_ops.iommu_get) { + return NULL; + } + return as->as_ops.iommu_get(as); +} + static const char *memory_region_type(MemoryRegion *mr) { if (memory_region_is_ram_device(mr)) { -- 2.7.4