- Improve the documentation of a couple of SGX functions handling

backing storage
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmM77w8ACgkQEsHwGGHe
 VUq8uhAAifAom4dzMQ0zsLP1nPY9Y7jqNdMvR1f4XcnWVQ5Ipvlkooy+m6wZr4Zd
 Yy5HT9fvlFNcZzH8V0vy/8Kf86mT7K6NUalvcBJhiZUkSiFaDrzTgEi7+Znqw402
 PVe/MiaUTfK1xokYIdzMmibsVh7SrL/8U4r4YWV0mQUYaGu0Fh7I+474Hd+4zH5F
 12sfq0aw/IyCj+XrvVCIkvdus416wmdgs5KSgDqvfTRAm44rrLaz6xfT0ONjAv7g
 Pzs4eRgxOgxDJRpumoAw+UGC23FWDfKIvZOLiczrFdBHZMmFPYkOK2wrICacHZx0
 I/DpwPk4sHKFFKjdXAqHDtLPwXp1D0xRN1Nw4UO5uSuj1XzjgPvBFjZ+zjM3EZMe
 OjzUYC1Qt2OrCYEXAot9tb9e0jqrg2hD9nCXrVszlXMbOyKX6l8BURf+2uzsXvq0
 tAdfWl3awn6OpX3MxHwxuSq70BS8+KgizAgkHbimyJnPcPgFWa9b7fwp/iYbJF2U
 g6vMUyK0r3pomfmXFed+QCZ7CD1tGGharLoa2/aQxshcffPrhG9CN6As769oxt1Z
 m4I17yi8YViEQyAyvJ5GxpCJykVByZUsbjUnE4uDHBrQRmeN5D2SMcYvYF7J2AVV
 up81qj/TOsWEqnP/h1B6K1rz700P/tQK/ebk4uRdacN/+9JyxPo=
 =lezL
 -----END PGP SIGNATURE-----

Merge tag 'x86_sgx_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SGX update from Borislav Petkov:

 - Improve the documentation of a couple of SGX functions handling
   backing storage

* tag 'x86_sgx_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Improve comments for sgx_encl_lookup/alloc_backing()
This commit is contained in:
Linus Torvalds 2022-10-04 09:17:44 -07:00
commit ba94a7a900
2 changed files with 14 additions and 9 deletions

View File

@ -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
@ -917,7 +920,7 @@ static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl,
}
/**
* 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
@ -929,7 +932,7 @@ 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);
@ -1004,7 +1007,7 @@ 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
@ -1012,7 +1015,9 @@ 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,
@ -1025,7 +1030,7 @@ 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);
@ -1043,15 +1048,17 @@ 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);
}
/**

View File

@ -107,8 +107,6 @@ bool current_is_ksgxd(void);
void sgx_encl_release(struct kref *ref);
int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl);
int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
struct sgx_backing *backing);
int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
struct sgx_backing *backing);
void sgx_encl_put_backing(struct sgx_backing *backing);