diff options
Diffstat (limited to 'arch/x86/kernel/cpu/sgx/encl.c')
| -rw-r--r-- | arch/x86/kernel/cpu/sgx/encl.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index 24c1bb8eb196..1ec20807de1e 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -12,6 +12,9 @@ #include "encls.h" #include "sgx.h" +static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index, + struct sgx_backing *backing); + #define PCMDS_PER_PAGE (PAGE_SIZE / sizeof(struct sgx_pcmd)) /* * 32 PCMD entries share a PCMD page. PCMD_FIRST_MASK is used to @@ -344,8 +347,11 @@ static vm_fault_t sgx_encl_eaug_page(struct vm_area_struct *vma, } va_page = sgx_encl_grow(encl, false); - if (IS_ERR(va_page)) + if (IS_ERR(va_page)) { + if (PTR_ERR(va_page) == -EBUSY) + vmret = VM_FAULT_NOPAGE; goto err_out_epc; + } if (va_page) list_add(&va_page->list, &encl->va_pages); @@ -906,15 +912,14 @@ const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl) static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl, pgoff_t index) { - struct inode *inode = encl->backing->f_path.dentry->d_inode; - struct address_space *mapping = inode->i_mapping; + struct address_space *mapping = encl->backing->f_mapping; gfp_t gfpmask = mapping_gfp_mask(mapping); return shmem_read_mapping_page_gfp(mapping, index, gfpmask); } /** - * sgx_encl_get_backing() - Pin the backing storage + * __sgx_encl_get_backing() - Pin the backing storage * @encl: an enclave pointer * @page_index: enclave page index * @backing: data for accessing backing storage for the page @@ -926,7 +931,7 @@ static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl, * 0 on success, * -errno otherwise. */ -static int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index, +static int __sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index, struct sgx_backing *backing) { pgoff_t page_pcmd_off = sgx_encl_get_backing_page_pcmd_offset(encl, page_index); @@ -1001,7 +1006,7 @@ static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl) } /** - * sgx_encl_alloc_backing() - allocate a new backing storage page + * sgx_encl_alloc_backing() - create a new backing storage page * @encl: an enclave pointer * @page_index: enclave page index * @backing: data for accessing backing storage for the page @@ -1009,7 +1014,9 @@ static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl) * When called from ksgxd, sets the active memcg from one of the * mms in the enclave's mm_list prior to any backing page allocation, * in order to ensure that shmem page allocations are charged to the - * enclave. + * enclave. Create a backing page for loading data back into an EPC page with + * ELDU. This function takes a reference on a new backing page which + * must be dropped with a corresponding call to sgx_encl_put_backing(). * * Return: * 0 on success, @@ -1022,7 +1029,7 @@ int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index, struct mem_cgroup *memcg = set_active_memcg(encl_memcg); int ret; - ret = sgx_encl_get_backing(encl, page_index, backing); + ret = __sgx_encl_get_backing(encl, page_index, backing); set_active_memcg(memcg); mem_cgroup_put(encl_memcg); @@ -1040,15 +1047,17 @@ int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index, * It is the caller's responsibility to ensure that it is appropriate to use * sgx_encl_lookup_backing() rather than sgx_encl_alloc_backing(). If lookup is * not used correctly, this will cause an allocation which is not accounted for. + * This function takes a reference on an existing backing page which must be + * dropped with a corresponding call to sgx_encl_put_backing(). * * Return: * 0 on success, * -errno otherwise. */ -int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index, +static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index, struct sgx_backing *backing) { - return sgx_encl_get_backing(encl, page_index, backing); + return __sgx_encl_get_backing(encl, page_index, backing); } /** |