diff options
Diffstat (limited to 'drivers/iommu/iommufd/device.c')
| -rw-r--r-- | drivers/iommu/iommufd/device.c | 74 |
1 files changed, 69 insertions, 5 deletions
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index cd5d8ab907f9..59fec5783eb9 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -486,6 +486,7 @@ iommufd_access_create(struct iommufd_ctx *ictx, iommufd_ctx_get(ictx); iommufd_object_finalize(ictx, &access->obj); *id = access->obj.id; + mutex_init(&access->ioas_lock); return access; } EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD); @@ -505,26 +506,60 @@ void iommufd_access_destroy(struct iommufd_access *access) } EXPORT_SYMBOL_NS_GPL(iommufd_access_destroy, IOMMUFD); +void iommufd_access_detach(struct iommufd_access *access) +{ + struct iommufd_ioas *cur_ioas = access->ioas; + + mutex_lock(&access->ioas_lock); + if (WARN_ON(!access->ioas)) + goto out; + /* + * Set ioas to NULL to block any further iommufd_access_pin_pages(). + * iommufd_access_unpin_pages() can continue using access->ioas_unpin. + */ + access->ioas = NULL; + + if (access->ops->unmap) { + mutex_unlock(&access->ioas_lock); + access->ops->unmap(access->data, 0, ULONG_MAX); + mutex_lock(&access->ioas_lock); + } + iopt_remove_access(&cur_ioas->iopt, access); + refcount_dec(&cur_ioas->obj.users); +out: + access->ioas_unpin = NULL; + mutex_unlock(&access->ioas_lock); +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_detach, IOMMUFD); + int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id) { struct iommufd_ioas *new_ioas; int rc = 0; - if (access->ioas) + mutex_lock(&access->ioas_lock); + if (WARN_ON(access->ioas || access->ioas_unpin)) { + mutex_unlock(&access->ioas_lock); return -EINVAL; + } new_ioas = iommufd_get_ioas(access->ictx, ioas_id); - if (IS_ERR(new_ioas)) + if (IS_ERR(new_ioas)) { + mutex_unlock(&access->ioas_lock); return PTR_ERR(new_ioas); + } rc = iopt_add_access(&new_ioas->iopt, access); if (rc) { + mutex_unlock(&access->ioas_lock); iommufd_put_object(&new_ioas->obj); return rc; } iommufd_ref_to_users(&new_ioas->obj); access->ioas = new_ioas; + access->ioas_unpin = new_ioas; + mutex_unlock(&access->ioas_lock); return 0; } EXPORT_SYMBOL_NS_GPL(iommufd_access_attach, IOMMUFD); @@ -579,8 +614,8 @@ void iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova, void iommufd_access_unpin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; @@ -588,6 +623,17 @@ void iommufd_access_unpin_pages(struct iommufd_access *access, WARN_ON(check_add_overflow(iova, length - 1, &last_iova))) return; + mutex_lock(&access->ioas_lock); + /* + * The driver must be doing something wrong if it calls this before an + * iommufd_access_attach() or after an iommufd_access_detach(). + */ + if (WARN_ON(!access->ioas_unpin)) { + mutex_unlock(&access->ioas_lock); + return; + } + iopt = &access->ioas_unpin->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) iopt_area_remove_access( @@ -597,6 +643,7 @@ void iommufd_access_unpin_pages(struct iommufd_access *access, min(last_iova, iopt_area_last_iova(area)))); WARN_ON(!iopt_area_contig_done(&iter)); up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); } EXPORT_SYMBOL_NS_GPL(iommufd_access_unpin_pages, IOMMUFD); @@ -642,8 +689,8 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length, struct page **out_pages, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; int rc; @@ -658,6 +705,13 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -688,6 +742,7 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return 0; err_remove: @@ -702,6 +757,7 @@ err_remove: iopt_area_last_iova(area)))); } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); @@ -721,8 +777,8 @@ EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, void *data, size_t length, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; struct iopt_area *area; unsigned long last_iova; int rc; @@ -732,6 +788,13 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -758,6 +821,7 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, rc = -ENOENT; err_out: up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } EXPORT_SYMBOL_NS_GPL(iommufd_access_rw, IOMMUFD); |