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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-12 13:11:26 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-12 13:11:26 -0700 |
commit | 467590e055f5c714fb457803250415879d0da9e5 (patch) | |
tree | 7533a26dcd19023d5eeac54f62432097c85f4ef3 /drivers/vfio | |
parent | 763f96944c954ce0e00a10a7bdfe29adbe4f92eb (diff) | |
parent | c1abca96b252a9627f99f39215b84e5de92bf1e3 (diff) | |
download | linux-stable-467590e055f5c714fb457803250415879d0da9e5.tar.gz linux-stable-467590e055f5c714fb457803250415879d0da9e5.tar.bz2 linux-stable-467590e055f5c714fb457803250415879d0da9e5.zip |
Merge tag 'vfio-v4.18-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Bind type1 task tracking to group_leader to facilitate vCPU hotplug
in QEMU (Alex Williamson)
- Sample mdev display drivers, including region-based host and guest
Linux drivers and bochs compatible dmabuf device
(Gerd Hoffmann)
- Fix vfio-platform reset module leak (Geert Uytterhoeven)
- vfio-platform error message consistency (Geert Uytterhoeven)
- Global checking for mdev uuid collisions rather than per parent
device (Alex Williamson)
- Use match_string() helper (Yisheng Xie)
- vfio-platform PM domain fixes (Geert Uytterhoeven)
- Fix sample mbochs driver build dependency (Arnd Bergmann)
* tag 'vfio-v4.18-rc1' of git://github.com/awilliam/linux-vfio:
samples: mbochs: add DMA_SHARED_BUFFER dependency
vfio: platform: Fix using devices in PM Domains
vfio: use match_string() helper
vfio/mdev: Re-order sysfs attribute creation
vfio/mdev: Check globally for duplicate devices
vfio: platform: Make printed error messages more consistent
vfio: platform: Fix reset module leak in error path
sample: vfio bochs vbe display (host device for bochs-drm)
sample: vfio mdev display - guest driver
sample: vfio mdev display - host device
vfio/type1: Fix task tracking for QEMU vCPU hotplug
Diffstat (limited to 'drivers/vfio')
-rw-r--r-- | drivers/vfio/mdev/mdev_core.c | 102 | ||||
-rw-r--r-- | drivers/vfio/mdev/mdev_private.h | 2 | ||||
-rw-r--r-- | drivers/vfio/mdev/mdev_sysfs.c | 14 | ||||
-rw-r--r-- | drivers/vfio/platform/vfio_platform_common.c | 30 | ||||
-rw-r--r-- | drivers/vfio/vfio.c | 11 | ||||
-rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 73 |
6 files changed, 116 insertions, 116 deletions
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 126991046eb7..0212f0ee8aea 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -66,34 +66,6 @@ uuid_le mdev_uuid(struct mdev_device *mdev) } EXPORT_SYMBOL(mdev_uuid); -static int _find_mdev_device(struct device *dev, void *data) -{ - struct mdev_device *mdev; - - if (!dev_is_mdev(dev)) - return 0; - - mdev = to_mdev_device(dev); - - if (uuid_le_cmp(mdev->uuid, *(uuid_le *)data) == 0) - return 1; - - return 0; -} - -static bool mdev_device_exist(struct mdev_parent *parent, uuid_le uuid) -{ - struct device *dev; - - dev = device_find_child(parent->dev, &uuid, _find_mdev_device); - if (dev) { - put_device(dev); - return true; - } - - return false; -} - /* Should be called holding parent_list_lock */ static struct mdev_parent *__find_parent_device(struct device *dev) { @@ -221,7 +193,6 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops) } kref_init(&parent->ref); - mutex_init(&parent->lock); parent->dev = dev; parent->ops = ops; @@ -297,6 +268,10 @@ static void mdev_device_release(struct device *dev) { struct mdev_device *mdev = to_mdev_device(dev); + mutex_lock(&mdev_list_lock); + list_del(&mdev->next); + mutex_unlock(&mdev_list_lock); + dev_dbg(&mdev->dev, "MDEV: destroying\n"); kfree(mdev); } @@ -304,7 +279,7 @@ static void mdev_device_release(struct device *dev) int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) { int ret; - struct mdev_device *mdev; + struct mdev_device *mdev, *tmp; struct mdev_parent *parent; struct mdev_type *type = to_mdev_type(kobj); @@ -312,21 +287,28 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) if (!parent) return -EINVAL; - mutex_lock(&parent->lock); + mutex_lock(&mdev_list_lock); /* Check for duplicate */ - if (mdev_device_exist(parent, uuid)) { - ret = -EEXIST; - goto create_err; + list_for_each_entry(tmp, &mdev_list, next) { + if (!uuid_le_cmp(tmp->uuid, uuid)) { + mutex_unlock(&mdev_list_lock); + ret = -EEXIST; + goto mdev_fail; + } } mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); if (!mdev) { + mutex_unlock(&mdev_list_lock); ret = -ENOMEM; - goto create_err; + goto mdev_fail; } memcpy(&mdev->uuid, &uuid, sizeof(uuid_le)); + list_add(&mdev->next, &mdev_list); + mutex_unlock(&mdev_list_lock); + mdev->parent = parent; kref_init(&mdev->ref); @@ -338,35 +320,28 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) ret = device_register(&mdev->dev); if (ret) { put_device(&mdev->dev); - goto create_err; + goto mdev_fail; } ret = mdev_device_create_ops(kobj, mdev); if (ret) - goto create_failed; + goto create_fail; ret = mdev_create_sysfs_files(&mdev->dev, type); if (ret) { mdev_device_remove_ops(mdev, true); - goto create_failed; + goto create_fail; } mdev->type_kobj = kobj; + mdev->active = true; dev_dbg(&mdev->dev, "MDEV: created\n"); - mutex_unlock(&parent->lock); - - mutex_lock(&mdev_list_lock); - list_add(&mdev->next, &mdev_list); - mutex_unlock(&mdev_list_lock); - - return ret; + return 0; -create_failed: +create_fail: device_unregister(&mdev->dev); - -create_err: - mutex_unlock(&parent->lock); +mdev_fail: mdev_put_parent(parent); return ret; } @@ -377,44 +352,39 @@ int mdev_device_remove(struct device *dev, bool force_remove) struct mdev_parent *parent; struct mdev_type *type; int ret; - bool found = false; mdev = to_mdev_device(dev); mutex_lock(&mdev_list_lock); list_for_each_entry(tmp, &mdev_list, next) { - if (tmp == mdev) { - found = true; + if (tmp == mdev) break; - } } - if (found) - list_del(&mdev->next); + if (tmp != mdev) { + mutex_unlock(&mdev_list_lock); + return -ENODEV; + } - mutex_unlock(&mdev_list_lock); + if (!mdev->active) { + mutex_unlock(&mdev_list_lock); + return -EAGAIN; + } - if (!found) - return -ENODEV; + mdev->active = false; + mutex_unlock(&mdev_list_lock); type = to_mdev_type(mdev->type_kobj); parent = mdev->parent; - mutex_lock(&parent->lock); ret = mdev_device_remove_ops(mdev, force_remove); if (ret) { - mutex_unlock(&parent->lock); - - mutex_lock(&mdev_list_lock); - list_add(&mdev->next, &mdev_list); - mutex_unlock(&mdev_list_lock); - + mdev->active = true; return ret; } mdev_remove_sysfs_files(dev, type); device_unregister(dev); - mutex_unlock(&parent->lock); mdev_put_parent(parent); return 0; diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h index a9cefd70a705..b5819b7d7ef7 100644 --- a/drivers/vfio/mdev/mdev_private.h +++ b/drivers/vfio/mdev/mdev_private.h @@ -20,7 +20,6 @@ struct mdev_parent { struct device *dev; const struct mdev_parent_ops *ops; struct kref ref; - struct mutex lock; struct list_head next; struct kset *mdev_types_kset; struct list_head type_list; @@ -34,6 +33,7 @@ struct mdev_device { struct kref ref; struct list_head next; struct kobject *type_kobj; + bool active; }; #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c index 802df210929b..249472f05509 100644 --- a/drivers/vfio/mdev/mdev_sysfs.c +++ b/drivers/vfio/mdev/mdev_sysfs.c @@ -257,24 +257,24 @@ int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type) { int ret; - ret = sysfs_create_files(&dev->kobj, mdev_device_attrs); - if (ret) - return ret; - ret = sysfs_create_link(type->devices_kobj, &dev->kobj, dev_name(dev)); if (ret) - goto device_link_failed; + return ret; ret = sysfs_create_link(&dev->kobj, &type->kobj, "mdev_type"); if (ret) goto type_link_failed; + ret = sysfs_create_files(&dev->kobj, mdev_device_attrs); + if (ret) + goto create_files_failed; + return ret; +create_files_failed: + sysfs_remove_link(&dev->kobj, "mdev_type"); type_link_failed: sysfs_remove_link(type->devices_kobj, dev_name(dev)); -device_link_failed: - sysfs_remove_files(&dev->kobj, mdev_device_attrs); return ret; } diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index 4c27f4be3c3d..c0cd824be2b7 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -17,6 +17,7 @@ #include <linux/iommu.h> #include <linux/module.h> #include <linux/mutex.h> +#include <linux/pm_runtime.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/uaccess.h> @@ -239,6 +240,7 @@ static void vfio_platform_release(void *device_data) ret, extra_dbg ? extra_dbg : ""); WARN_ON(1); } + pm_runtime_put(vdev->device); vfio_platform_regions_cleanup(vdev); vfio_platform_irq_cleanup(vdev); } @@ -269,6 +271,10 @@ static int vfio_platform_open(void *device_data) if (ret) goto err_irq; + ret = pm_runtime_get_sync(vdev->device); + if (ret < 0) + goto err_pm; + ret = vfio_platform_call_reset(vdev, &extra_dbg); if (ret && vdev->reset_required) { dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n", @@ -283,6 +289,8 @@ static int vfio_platform_open(void *device_data) return 0; err_rst: + pm_runtime_put(vdev->device); +err_pm: vfio_platform_irq_cleanup(vdev); err_irq: vfio_platform_regions_cleanup(vdev); @@ -630,8 +638,7 @@ static int vfio_platform_of_probe(struct vfio_platform_device *vdev, ret = device_property_read_string(dev, "compatible", &vdev->compat); if (ret) - pr_err("VFIO: cannot retrieve compat for %s\n", - vdev->name); + pr_err("VFIO: Cannot retrieve compat for %s\n", vdev->name); return ret; } @@ -673,7 +680,7 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, ret = vfio_platform_get_reset(vdev); if (ret && vdev->reset_required) { - pr_err("vfio: no reset function found for device %s\n", + pr_err("VFIO: No reset function found for device %s\n", vdev->name); return ret; } @@ -681,18 +688,24 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, group = vfio_iommu_group_get(dev); if (!group) { pr_err("VFIO: No IOMMU group for device %s\n", vdev->name); - return -EINVAL; + ret = -EINVAL; + goto put_reset; } ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev); - if (ret) { - vfio_iommu_group_put(group, dev); - return ret; - } + if (ret) + goto put_iommu; mutex_init(&vdev->igate); + pm_runtime_enable(vdev->device); return 0; + +put_iommu: + vfio_iommu_group_put(group, dev); +put_reset: + vfio_platform_put_reset(vdev); + return ret; } EXPORT_SYMBOL_GPL(vfio_platform_probe_common); @@ -703,6 +716,7 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev) vdev = vfio_del_group_dev(dev); if (vdev) { + pm_runtime_disable(vdev->device); vfio_platform_put_reset(vdev); vfio_iommu_group_put(dev->iommu_group, dev); } diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 721f97f8dac1..64833879f75d 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -630,8 +630,6 @@ static const char * const vfio_driver_whitelist[] = { "pci-stub" }; static bool vfio_dev_whitelisted(struct device *dev, struct device_driver *drv) { - int i; - if (dev_is_pci(dev)) { struct pci_dev *pdev = to_pci_dev(dev); @@ -639,12 +637,9 @@ static bool vfio_dev_whitelisted(struct device *dev, struct device_driver *drv) return true; } - for (i = 0; i < ARRAY_SIZE(vfio_driver_whitelist); i++) { - if (!strcmp(drv->name, vfio_driver_whitelist[i])) - return true; - } - - return false; + return match_string(vfio_driver_whitelist, + ARRAY_SIZE(vfio_driver_whitelist), + drv->name) >= 0; } /* diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 3c082451ab1a..2c75b33db4ac 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -83,6 +83,7 @@ struct vfio_dma { size_t size; /* Map size (bytes) */ int prot; /* IOMMU_READ/WRITE */ bool iommu_mapped; + bool lock_cap; /* capable(CAP_IPC_LOCK) */ struct task_struct *task; struct rb_root pfn_list; /* Ex-user pinned pfn list */ }; @@ -253,29 +254,25 @@ static int vfio_iova_put_vfio_pfn(struct vfio_dma *dma, struct vfio_pfn *vpfn) return ret; } -static int vfio_lock_acct(struct task_struct *task, long npage, bool *lock_cap) +static int vfio_lock_acct(struct vfio_dma *dma, long npage, bool async) { struct mm_struct *mm; - bool is_current; int ret; if (!npage) return 0; - is_current = (task->mm == current->mm); - - mm = is_current ? task->mm : get_task_mm(task); + mm = async ? get_task_mm(dma->task) : dma->task->mm; if (!mm) return -ESRCH; /* process exited */ ret = down_write_killable(&mm->mmap_sem); if (!ret) { if (npage > 0) { - if (lock_cap ? !*lock_cap : - !has_capability(task, CAP_IPC_LOCK)) { + if (!dma->lock_cap) { unsigned long limit; - limit = task_rlimit(task, + limit = task_rlimit(dma->task, RLIMIT_MEMLOCK) >> PAGE_SHIFT; if (mm->locked_vm + npage > limit) @@ -289,7 +286,7 @@ static int vfio_lock_acct(struct task_struct *task, long npage, bool *lock_cap) up_write(&mm->mmap_sem); } - if (!is_current) + if (async) mmput(mm); return ret; @@ -400,7 +397,7 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, */ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, long npage, unsigned long *pfn_base, - bool lock_cap, unsigned long limit) + unsigned long limit) { unsigned long pfn = 0; long ret, pinned = 0, lock_acct = 0; @@ -423,7 +420,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, * pages are already counted against the user. */ if (!rsvd && !vfio_find_vpfn(dma, iova)) { - if (!lock_cap && current->mm->locked_vm + 1 > limit) { + if (!dma->lock_cap && current->mm->locked_vm + 1 > limit) { put_pfn(*pfn_base, dma->prot); pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__, limit << PAGE_SHIFT); @@ -449,7 +446,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, } if (!rsvd && !vfio_find_vpfn(dma, iova)) { - if (!lock_cap && + if (!dma->lock_cap && current->mm->locked_vm + lock_acct + 1 > limit) { put_pfn(pfn, dma->prot); pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", @@ -462,7 +459,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, } out: - ret = vfio_lock_acct(current, lock_acct, &lock_cap); + ret = vfio_lock_acct(dma, lock_acct, false); unpin_out: if (ret) { @@ -493,7 +490,7 @@ static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova, } if (do_accounting) - vfio_lock_acct(dma->task, locked - unlocked, NULL); + vfio_lock_acct(dma, locked - unlocked, true); return unlocked; } @@ -510,7 +507,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr, ret = vaddr_get_pfn(mm, vaddr, dma->prot, pfn_base); if (!ret && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { - ret = vfio_lock_acct(dma->task, 1, NULL); + ret = vfio_lock_acct(dma, 1, true); if (ret) { put_pfn(*pfn_base, dma->prot); if (ret == -ENOMEM) @@ -537,7 +534,7 @@ static int vfio_unpin_page_external(struct vfio_dma *dma, dma_addr_t iova, unlocked = vfio_iova_put_vfio_pfn(dma, vpfn); if (do_accounting) - vfio_lock_acct(dma->task, -unlocked, NULL); + vfio_lock_acct(dma, -unlocked, true); return unlocked; } @@ -829,7 +826,7 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma, unlocked += vfio_sync_unpin(dma, domain, &unmapped_region_list); if (do_accounting) { - vfio_lock_acct(dma->task, -unlocked, NULL); + vfio_lock_acct(dma, -unlocked, true); return 0; } return unlocked; @@ -1044,14 +1041,12 @@ static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma, size_t size = map_size; long npage; unsigned long pfn, limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; - bool lock_cap = capable(CAP_IPC_LOCK); int ret = 0; while (size) { /* Pin a contiguous chunk of memory */ npage = vfio_pin_pages_remote(dma, vaddr + dma->size, - size >> PAGE_SHIFT, &pfn, - lock_cap, limit); + size >> PAGE_SHIFT, &pfn, limit); if (npage <= 0) { WARN_ON(!npage); ret = (int)npage; @@ -1126,8 +1121,36 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu, dma->iova = iova; dma->vaddr = vaddr; dma->prot = prot; - get_task_struct(current); - dma->task = current; + + /* + * We need to be able to both add to a task's locked memory and test + * against the locked memory limit and we need to be able to do both + * outside of this call path as pinning can be asynchronous via the + * external interfaces for mdev devices. RLIMIT_MEMLOCK requires a + * task_struct and VM locked pages requires an mm_struct, however + * holding an indefinite mm reference is not recommended, therefore we + * only hold a reference to a task. We could hold a reference to + * current, however QEMU uses this call path through vCPU threads, + * which can be killed resulting in a NULL mm and failure in the unmap + * path when called via a different thread. Avoid this problem by + * using the group_leader as threads within the same group require + * both CLONE_THREAD and CLONE_VM and will therefore use the same + * mm_struct. + * + * Previously we also used the task for testing CAP_IPC_LOCK at the + * time of pinning and accounting, however has_capability() makes use + * of real_cred, a copy-on-write field, so we can't guarantee that it + * matches group_leader, or in fact that it might not change by the + * time it's evaluated. If a process were to call MAP_DMA with + * CAP_IPC_LOCK but later drop it, it doesn't make sense that they + * possibly see different results for an iommu_mapped vfio_dma vs + * externally mapped. Therefore track CAP_IPC_LOCK in vfio_dma at the + * time of calling MAP_DMA. + */ + get_task_struct(current->group_leader); + dma->task = current->group_leader; + dma->lock_cap = capable(CAP_IPC_LOCK); + dma->pfn_list = RB_ROOT; /* Insert zero-sized and grow as we map chunks of it */ @@ -1162,7 +1185,6 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, struct vfio_domain *d; struct rb_node *n; unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; - bool lock_cap = capable(CAP_IPC_LOCK); int ret; /* Arbitrarily pick the first domain in the list for lookups */ @@ -1209,8 +1231,7 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, npage = vfio_pin_pages_remote(dma, vaddr, n >> PAGE_SHIFT, - &pfn, lock_cap, - limit); + &pfn, limit); if (npage <= 0) { WARN_ON(!npage); ret = (int)npage; @@ -1487,7 +1508,7 @@ static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu) if (!is_invalid_reserved_pfn(vpfn->pfn)) locked++; } - vfio_lock_acct(dma->task, locked - unlocked, NULL); + vfio_lock_acct(dma, locked - unlocked, true); } } |