From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752683AbbCaMPx (ORCPT ); Tue, 31 Mar 2015 08:15:53 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:23661 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752172AbbCaMPv (ORCPT ); Tue, 31 Mar 2015 08:15:51 -0400 From: Bob Liu To: xen-devel@lists.xenproject.org Cc: paul.durrant@citrix.com, david.vrabel@citrix.com, roger.pau@citrix.com, linux-kernel@vger.kernel.org, konrad.wilk@oracle.com, Wei Liu , Bob Liu , Boris Ostrovsky Subject: [PATCH RESEND 1/2] xenbus_client: Extend interface to support multi-page ring Date: Tue, 31 Mar 2015 20:15:26 +0800 Message-Id: <1427804127-11372-1-git-send-email-bob.liu@oracle.com> X-Mailer: git-send-email 1.7.10.4 X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wei Liu Originally Xen PV drivers only use single-page ring to pass along information. This might limit the throughput between frontend and backend. The patch extends Xenbus driver to support multi-page ring, which in general should improve throughput if ring is the bottleneck. Changes to various frontend / backend to adapt to the new interface are also included. Affected Xen drivers: * blkfront/back * netfront/back * pcifront/back The interface is documented, as before, in xenbus_client.c. Change in V2: * allow ring has arbitrary number of pages <= XENBUS_MAX_RING_PAGES Change in V3: * update function prototypes * carefully deal with types of different sizes Change in V4: * use PAGE_KERNEL instead of PAGE_KERNEL_IO to avoid breakage on Arm Change in V5: * fix off-by-one error and other minor glitches spotted by Mathew Daley Signed-off-by: Wei Liu Signed-off-by: Paul Durrant Signed-off-by: Bob Liu Cc: Konrad Wilk Cc: David Vrabel Cc: Boris Ostrovsky --- drivers/block/xen-blkback/xenbus.c | 5 +- drivers/block/xen-blkfront.c | 5 +- drivers/net/xen-netback/netback.c | 4 +- drivers/net/xen-netfront.c | 9 +- drivers/pci/xen-pcifront.c | 5 +- drivers/xen/xen-pciback/xenbus.c | 2 +- drivers/xen/xenbus/xenbus_client.c | 387 +++++++++++++++++++++++++++---------- include/xen/xenbus.h | 20 +- 8 files changed, 317 insertions(+), 120 deletions(-) diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index e3afe97..ff30259 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -193,7 +193,7 @@ fail: return ERR_PTR(-ENOMEM); } -static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page, +static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t gref, unsigned int evtchn) { int err; @@ -202,7 +202,8 @@ static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page, if (blkif->irq) return 0; - err = xenbus_map_ring_valloc(blkif->be->dev, shared_page, &blkif->blk_ring); + err = xenbus_map_ring_valloc(blkif->be->dev, &gref, 1, + &blkif->blk_ring); if (err < 0) return err; diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 37779e4..2c61cf8 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1245,6 +1245,7 @@ static int setup_blkring(struct xenbus_device *dev, struct blkfront_info *info) { struct blkif_sring *sring; + grant_ref_t gref; int err; info->ring_ref = GRANT_INVALID_REF; @@ -1257,13 +1258,13 @@ static int setup_blkring(struct xenbus_device *dev, SHARED_RING_INIT(sring); FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE); - err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring)); + err = xenbus_grant_ring(dev, info->ring.sring, 1, &gref); if (err < 0) { free_page((unsigned long)sring); info->ring.sring = NULL; goto fail; } - info->ring_ref = err; + info->ring_ref = gref; err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 997cf09..865203f 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1782,7 +1782,7 @@ int xenvif_map_frontend_rings(struct xenvif_queue *queue, int err = -ENOMEM; err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), - tx_ring_ref, &addr); + &tx_ring_ref, 1, &addr); if (err) goto err; @@ -1790,7 +1790,7 @@ int xenvif_map_frontend_rings(struct xenvif_queue *queue, BACK_RING_INIT(&queue->tx, txs, PAGE_SIZE); err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), - rx_ring_ref, &addr); + &rx_ring_ref, 1, &addr); if (err) goto err; diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index e9b960f..13f5e7f 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1486,6 +1486,7 @@ static int setup_netfront(struct xenbus_device *dev, { struct xen_netif_tx_sring *txs; struct xen_netif_rx_sring *rxs; + grant_ref_t gref; int err; queue->tx_ring_ref = GRANT_INVALID_REF; @@ -1502,10 +1503,10 @@ static int setup_netfront(struct xenbus_device *dev, SHARED_RING_INIT(txs); FRONT_RING_INIT(&queue->tx, txs, PAGE_SIZE); - err = xenbus_grant_ring(dev, virt_to_mfn(txs)); + err = xenbus_grant_ring(dev, txs, 1, &gref); if (err < 0) goto grant_tx_ring_fail; - queue->tx_ring_ref = err; + queue->tx_ring_ref = gref; rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); if (!rxs) { @@ -1516,10 +1517,10 @@ static int setup_netfront(struct xenbus_device *dev, SHARED_RING_INIT(rxs); FRONT_RING_INIT(&queue->rx, rxs, PAGE_SIZE); - err = xenbus_grant_ring(dev, virt_to_mfn(rxs)); + err = xenbus_grant_ring(dev, rxs, 1, &gref); if (err < 0) goto grant_rx_ring_fail; - queue->rx_ring_ref = err; + queue->rx_ring_ref = gref; if (feature_split_evtchn) err = setup_netfront_split(queue); diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..7cfd2db 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -777,12 +777,13 @@ static int pcifront_publish_info(struct pcifront_device *pdev) { int err = 0; struct xenbus_transaction trans; + grant_ref_t gref; - err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info)); + err = xenbus_grant_ring(pdev->xdev, pdev->sh_info, 1, &gref); if (err < 0) goto out; - pdev->gnt_ref = err; + pdev->gnt_ref = gref; err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn); if (err) diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c index fe17c80..98bc345 100644 --- a/drivers/xen/xen-pciback/xenbus.c +++ b/drivers/xen/xen-pciback/xenbus.c @@ -113,7 +113,7 @@ static int xen_pcibk_do_attach(struct xen_pcibk_device *pdev, int gnt_ref, "Attaching to frontend resources - gnt_ref=%d evtchn=%d\n", gnt_ref, remote_evtchn); - err = xenbus_map_ring_valloc(pdev->xdev, gnt_ref, &vaddr); + err = xenbus_map_ring_valloc(pdev->xdev, &gnt_ref, 1, &vaddr); if (err < 0) { xenbus_dev_fatal(pdev->xdev, err, "Error mapping other domain page in ours."); diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index ca74410..96b2011 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -52,17 +52,25 @@ struct xenbus_map_node { struct list_head next; union { - struct vm_struct *area; /* PV */ - struct page *page; /* HVM */ + struct { + struct vm_struct *area; + } pv; + struct { + struct page *pages[XENBUS_MAX_RING_PAGES]; + void *addr; + } hvm; }; - grant_handle_t handle; + grant_handle_t handles[XENBUS_MAX_RING_PAGES]; + unsigned int nr_handles; }; static DEFINE_SPINLOCK(xenbus_valloc_lock); static LIST_HEAD(xenbus_valloc_pages); struct xenbus_ring_ops { - int (*map)(struct xenbus_device *dev, int gnt, void **vaddr); + int (*map)(struct xenbus_device *dev, + grant_ref_t *gnt_refs, unsigned int nr_grefs, + void **vaddr); int (*unmap)(struct xenbus_device *dev, void *vaddr); }; @@ -355,17 +363,39 @@ static void xenbus_switch_fatal(struct xenbus_device *dev, int depth, int err, /** * xenbus_grant_ring * @dev: xenbus device - * @ring_mfn: mfn of ring to grant - - * Grant access to the given @ring_mfn to the peer of the given device. Return - * a grant reference on success, or -errno on error. On error, the device will - * switch to XenbusStateClosing, and the error will be saved in the store. + * @vaddr: starting virtual address of the ring + * @nr_pages: number of pages to be granted + * @grefs: grant reference array to be filled in + * + * Grant access to the given @vaddr to the peer of the given device. + * Then fill in @grefs with grant references. Return 0 on success, or + * -errno on error. On error, the device will switch to + * XenbusStateClosing, and the error will be saved in the store. */ -int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn) +int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr, + unsigned int nr_pages, grant_ref_t *grefs) { - int err = gnttab_grant_foreign_access(dev->otherend_id, ring_mfn, 0); - if (err < 0) - xenbus_dev_fatal(dev, err, "granting access to ring page"); + int err; + int i, j; + + for (i = 0; i < nr_pages; i++) { + unsigned long addr = (unsigned long)vaddr + + (PAGE_SIZE * i); + err = gnttab_grant_foreign_access(dev->otherend_id, + virt_to_mfn(addr), 0); + if (err < 0) { + xenbus_dev_fatal(dev, err, + "granting access to ring page"); + goto fail; + } + grefs[i] = err; + } + + return 0; + +fail: + for (j = 0; j < i; j++) + gnttab_end_foreign_access_ref(grefs[j], 0); return err; } EXPORT_SYMBOL_GPL(xenbus_grant_ring); @@ -419,62 +449,130 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn); /** * xenbus_map_ring_valloc * @dev: xenbus device - * @gnt_ref: grant reference + * @gnt_refs: grant reference array + * @nr_grefs: number of grant references * @vaddr: pointer to address to be filled out by mapping * - * Based on Rusty Russell's skeleton driver's map_page. - * Map a page of memory into this domain from another domain's grant table. - * xenbus_map_ring_valloc allocates a page of virtual address space, maps the - * page to that address, and sets *vaddr to that address. - * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h) - * or -ENOMEM on error. If an error is returned, device will switch to + * Map @nr_grefs pages of memory into this domain from another + * domain's grant table. xenbus_map_ring_valloc allocates @nr_grefs + * pages of virtual address space, maps the pages to that address, and + * sets *vaddr to that address. Returns 0 on success, and GNTST_* + * (see xen/include/interface/grant_table.h) or -ENOMEM / -EINVAL on + * error. If an error is returned, device will switch to * XenbusStateClosing and the error message will be saved in XenStore. */ -int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr) +int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs, + unsigned int nr_grefs, void **vaddr) { - return ring_ops->map(dev, gnt_ref, vaddr); + return ring_ops->map(dev, gnt_refs, nr_grefs, vaddr); } EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc); +/* N.B. sizeof(phys_addr_t) doesn't always equal to sizeof(unsigned + * long), e.g. 32-on-64. Caller is responsible for preparing the + * right array to feed into this function */ +static int __xenbus_map_ring(struct xenbus_device *dev, + grant_ref_t *gnt_refs, + unsigned int nr_grefs, + grant_handle_t *handles, + phys_addr_t *addrs, + unsigned int flags, + bool *leaked) +{ + struct gnttab_map_grant_ref map[XENBUS_MAX_RING_PAGES]; + struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES]; + int i, j; + int err = GNTST_okay; + + if (nr_grefs > XENBUS_MAX_RING_PAGES) + return -EINVAL; + + for (i = 0; i < nr_grefs; i++) { + memset(&map[i], 0, sizeof(map[i])); + gnttab_set_map_op(&map[i], addrs[i], flags, gnt_refs[i], + dev->otherend_id); + handles[i] = INVALID_GRANT_HANDLE; + } + + gnttab_batch_map(map, i); + + for (i = 0; i < nr_grefs; i++) { + if (map[i].status != GNTST_okay) { + err = map[i].status; + xenbus_dev_fatal(dev, map[i].status, + "mapping in shared page %d from domain %d", + gnt_refs[i], dev->otherend_id); + goto fail; + } else + handles[i] = map[i].handle; + } + + return GNTST_okay; + + fail: + for (i = j = 0; i < nr_grefs; i++) { + if (handles[i] != INVALID_GRANT_HANDLE) { + memset(&unmap[j], 0, sizeof(unmap[j])); + gnttab_set_unmap_op(&unmap[j], (phys_addr_t)addrs[i], + GNTMAP_host_map, handles[i]); + j++; + } + } + + if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, j)) + BUG(); + + *leaked = false; + for (i = 0; i < j; i++) { + if (unmap[i].status != GNTST_okay) { + *leaked = true; + break; + } + } + + return err; +} + static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev, - int gnt_ref, void **vaddr) + grant_ref_t *gnt_refs, + unsigned int nr_grefs, + void **vaddr) { - struct gnttab_map_grant_ref op = { - .flags = GNTMAP_host_map | GNTMAP_contains_pte, - .ref = gnt_ref, - .dom = dev->otherend_id, - }; struct xenbus_map_node *node; struct vm_struct *area; - pte_t *pte; + pte_t *ptes[XENBUS_MAX_RING_PAGES]; + phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES]; + int err = GNTST_okay; + int i; + bool leaked; *vaddr = NULL; + if (nr_grefs > XENBUS_MAX_RING_PAGES) + return -EINVAL; + node = kzalloc(sizeof(*node), GFP_KERNEL); if (!node) return -ENOMEM; - area = alloc_vm_area(PAGE_SIZE, &pte); + area = alloc_vm_area(PAGE_SIZE * nr_grefs, ptes); if (!area) { kfree(node); return -ENOMEM; } - op.host_addr = arbitrary_virt_to_machine(pte).maddr; + for (i = 0; i < nr_grefs; i++) + phys_addrs[i] = arbitrary_virt_to_machine(ptes[i]).maddr; - gnttab_batch_map(&op, 1); - - if (op.status != GNTST_okay) { - free_vm_area(area); - kfree(node); - xenbus_dev_fatal(dev, op.status, - "mapping in shared page %d from domain %d", - gnt_ref, dev->otherend_id); - return op.status; - } + err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles, + phys_addrs, + GNTMAP_host_map | GNTMAP_contains_pte, + &leaked); + if (err) + goto failed; - node->handle = op.handle; - node->area = area; + node->nr_handles = nr_grefs; + node->pv.area = area; spin_lock(&xenbus_valloc_lock); list_add(&node->next, &xenbus_valloc_pages); @@ -482,14 +580,33 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev, *vaddr = area->addr; return 0; + +failed: + if (!leaked) + free_vm_area(area); + else + pr_alert("leaking VM area %p size %u page(s)", area, nr_grefs); + + kfree(node); + return err; } static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev, - int gnt_ref, void **vaddr) + grant_ref_t *gnt_ref, + unsigned int nr_grefs, + void **vaddr) { struct xenbus_map_node *node; + int i; int err; void *addr; + bool leaked = false; + /* Why do we need two arrays? See comment of __xenbus_map_ring */ + phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES]; + unsigned long addrs[XENBUS_MAX_RING_PAGES]; + + if (nr_grefs > XENBUS_MAX_RING_PAGES) + return -EINVAL; *vaddr = NULL; @@ -497,15 +614,32 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev, if (!node) return -ENOMEM; - err = alloc_xenballooned_pages(1, &node->page, false /* lowmem */); + err = alloc_xenballooned_pages(nr_grefs, node->hvm.pages, + false /* lowmem */); if (err) goto out_err; - addr = pfn_to_kaddr(page_to_pfn(node->page)); + for (i = 0; i < nr_grefs; i++) { + unsigned long pfn = page_to_pfn(node->hvm.pages[i]); + phys_addrs[i] = (unsigned long)pfn_to_kaddr(pfn); + addrs[i] = (unsigned long)pfn_to_kaddr(pfn); + } + + err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles, + phys_addrs, GNTMAP_host_map, &leaked); + node->nr_handles = nr_grefs; - err = xenbus_map_ring(dev, gnt_ref, &node->handle, addr); if (err) - goto out_err_free_ballooned_pages; + goto out_free_ballooned_pages; + + addr = vmap(node->hvm.pages, nr_grefs, VM_MAP | VM_IOREMAP, + PAGE_KERNEL); + if (!addr) { + err = -ENOMEM; + goto out_xenbus_unmap_ring; + } + + node->hvm.addr = addr; spin_lock(&xenbus_valloc_lock); list_add(&node->next, &xenbus_valloc_pages); @@ -514,8 +648,16 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev, *vaddr = addr; return 0; - out_err_free_ballooned_pages: - free_xenballooned_pages(1, &node->page); + out_xenbus_unmap_ring: + if (!leaked) + xenbus_unmap_ring(dev, node->handles, node->nr_handles, + addrs); + else + pr_alert("leaking %p size %u page(s)", + addr, nr_grefs); + out_free_ballooned_pages: + if (!leaked) + free_xenballooned_pages(nr_grefs, node->hvm.pages); out_err: kfree(node); return err; @@ -525,35 +667,37 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev, /** * xenbus_map_ring * @dev: xenbus device - * @gnt_ref: grant reference - * @handle: pointer to grant handle to be filled - * @vaddr: address to be mapped to + * @gnt_refs: grant reference array + * @nr_grefs: number of grant reference + * @handles: pointer to grant handle to be filled + * @vaddrs: addresses to be mapped to + * @leaked: fail to clean up a failed map, caller should not free vaddr * - * Map a page of memory into this domain from another domain's grant table. + * Map pages of memory into this domain from another domain's grant table. * xenbus_map_ring does not allocate the virtual address space (you must do - * this yourself!). It only maps in the page to the specified address. + * this yourself!). It only maps in the pages to the specified address. * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h) - * or -ENOMEM on error. If an error is returned, device will switch to - * XenbusStateClosing and the error message will be saved in XenStore. + * or -ENOMEM / -EINVAL on error. If an error is returned, device will switch to + * XenbusStateClosing and the first error message will be saved in XenStore. + * Further more if we fail to map the ring, caller should check @leaked. + * If @leaked is not zero it means xenbus_map_ring fails to clean up, caller + * should not free the address space of @vaddr. */ -int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref, - grant_handle_t *handle, void *vaddr) +int xenbus_map_ring(struct xenbus_device *dev, grant_ref_t *gnt_refs, + unsigned int nr_grefs, grant_handle_t *handles, + unsigned long *vaddrs, bool *leaked) { - struct gnttab_map_grant_ref op; - - gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref, - dev->otherend_id); + phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES]; + int i; - gnttab_batch_map(&op, 1); + if (nr_grefs > XENBUS_MAX_RING_PAGES) + return -EINVAL; - if (op.status != GNTST_okay) { - xenbus_dev_fatal(dev, op.status, - "mapping in shared page %d from domain %d", - gnt_ref, dev->otherend_id); - } else - *handle = op.handle; + for (i = 0; i < nr_grefs; i++) + phys_addrs[i] = (unsigned long)vaddrs[i]; - return op.status; + return __xenbus_map_ring(dev, gnt_refs, nr_grefs, handles, + phys_addrs, GNTMAP_host_map, leaked); } EXPORT_SYMBOL_GPL(xenbus_map_ring); @@ -579,14 +723,15 @@ EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree); static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr) { struct xenbus_map_node *node; - struct gnttab_unmap_grant_ref op = { - .host_addr = (unsigned long)vaddr, - }; + struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES]; unsigned int level; + int i; + bool leaked = false; + int err; spin_lock(&xenbus_valloc_lock); list_for_each_entry(node, &xenbus_valloc_pages, next) { - if (node->area->addr == vaddr) { + if (node->pv.area->addr == vaddr) { list_del(&node->next); goto found; } @@ -601,22 +746,41 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr) return GNTST_bad_virt_addr; } - op.handle = node->handle; - op.host_addr = arbitrary_virt_to_machine( - lookup_address((unsigned long)vaddr, &level)).maddr; + for (i = 0; i < node->nr_handles; i++) { + unsigned long addr; + + memset(&unmap[i], 0, sizeof(unmap[i])); + addr = (unsigned long)vaddr + (PAGE_SIZE * i); + unmap[i].host_addr = arbitrary_virt_to_machine( + lookup_address(addr, &level)).maddr; + unmap[i].dev_bus_addr = 0; + unmap[i].handle = node->handles[i]; + } - if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1)) + if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, i)) BUG(); - if (op.status == GNTST_okay) - free_vm_area(node->area); + err = GNTST_okay; + leaked = false; + for (i = 0; i < node->nr_handles; i++) { + if (unmap[i].status != GNTST_okay) { + leaked = true; + xenbus_dev_error(dev, unmap[i].status, + "unmapping page at handle %d error %d", + node->handles[i], unmap[i].status); + err = unmap[i].status; + break; + } + } + + if (!leaked) + free_vm_area(node->pv.area); else - xenbus_dev_error(dev, op.status, - "unmapping page at handle %d error %d", - node->handle, op.status); + pr_alert("leaking VM area %p size %u page(s)", + node->pv.area, node->nr_handles); kfree(node); - return op.status; + return err; } static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr) @@ -624,10 +788,12 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr) int rv; struct xenbus_map_node *node; void *addr; + unsigned long addrs[XENBUS_MAX_RING_PAGES]; + int i; spin_lock(&xenbus_valloc_lock); list_for_each_entry(node, &xenbus_valloc_pages, next) { - addr = pfn_to_kaddr(page_to_pfn(node->page)); + addr = node->hvm.addr; if (addr == vaddr) { list_del(&node->next); goto found; @@ -643,12 +809,16 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr) return GNTST_bad_virt_addr; } - rv = xenbus_unmap_ring(dev, node->handle, addr); + for (i = 0; i < node->nr_handles; i++) + addrs[i] = (unsigned long)pfn_to_kaddr(page_to_pfn(node->hvm.pages[i])); + rv = xenbus_unmap_ring(dev, node->handles, node->nr_handles, + addrs); if (!rv) - free_xenballooned_pages(1, &node->page); + vunmap(vaddr); else - WARN(1, "Leaking %p\n", vaddr); + WARN(1, "Leaking %p, size %u page(s)\n", vaddr, + node->nr_handles); kfree(node); return rv; @@ -657,29 +827,44 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr) /** * xenbus_unmap_ring * @dev: xenbus device - * @handle: grant handle - * @vaddr: addr to unmap + * @handles: grant handle array + * @nr_handles: number of handles in the array + * @vaddrs: addresses to unmap * - * Unmap a page of memory in this domain that was imported from another domain. + * Unmap memory in this domain that was imported from another domain. * Returns 0 on success and returns GNTST_* on error * (see xen/include/interface/grant_table.h). */ int xenbus_unmap_ring(struct xenbus_device *dev, - grant_handle_t handle, void *vaddr) + grant_handle_t *handles, unsigned int nr_handles, + unsigned long *vaddrs) { - struct gnttab_unmap_grant_ref op; + struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES]; + int i; + int err; - gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map, handle); + if (nr_handles > XENBUS_MAX_RING_PAGES) + return -EINVAL; - if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1)) + for (i = 0; i < nr_handles; i++) + gnttab_set_unmap_op(&unmap[i], vaddrs[i], + GNTMAP_host_map, handles[i]); + + if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, i)) BUG(); - if (op.status != GNTST_okay) - xenbus_dev_error(dev, op.status, - "unmapping page at handle %d error %d", - handle, op.status); + err = GNTST_okay; + for (i = 0; i < nr_handles; i++) { + if (unmap[i].status != GNTST_okay) { + xenbus_dev_error(dev, unmap[i].status, + "unmapping page at handle %d error %d", + handles[i], unmap[i].status); + err = unmap[i].status; + break; + } + } - return op.status; + return err; } EXPORT_SYMBOL_GPL(xenbus_unmap_ring); diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index b0f1c9e..289c0b5 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -46,6 +46,10 @@ #include #include +#define XENBUS_MAX_RING_PAGE_ORDER 4 +#define XENBUS_MAX_RING_PAGES (1U << XENBUS_MAX_RING_PAGE_ORDER) +#define INVALID_GRANT_HANDLE (~0U) + /* Register callback to watch this node. */ struct xenbus_watch { @@ -199,15 +203,19 @@ int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch, const char *pathfmt, ...); int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state); -int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn); -int xenbus_map_ring_valloc(struct xenbus_device *dev, - int gnt_ref, void **vaddr); -int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref, - grant_handle_t *handle, void *vaddr); +int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr, + unsigned int nr_pages, grant_ref_t *grefs); +int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs, + unsigned int nr_grefs, void **vaddr); +int xenbus_map_ring(struct xenbus_device *dev, + grant_ref_t *gnt_refs, unsigned int nr_grefs, + grant_handle_t *handles, unsigned long *vaddrs, + bool *leaked); int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr); int xenbus_unmap_ring(struct xenbus_device *dev, - grant_handle_t handle, void *vaddr); + grant_handle_t *handles, unsigned int nr_handles, + unsigned long *vaddrs); int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port); int xenbus_free_evtchn(struct xenbus_device *dev, int port); -- 1.8.3.1