diff options
Diffstat (limited to 'drivers/s390/cio/vfio_ccw_cp.c')
| -rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index 9a2a39df1056..c532939c1c3f 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -23,9 +23,13 @@ #define CCWCHAIN_LEN_MAX 256 struct pfn_array { + /* Starting guest physical I/O address. */ unsigned long pa_iova; + /* Array that stores PFNs of the pages need to pin. */ unsigned long *pa_iova_pfn; + /* Array that receives PFNs of the pages pinned. */ unsigned long *pa_pfn; + /* Number of pages to pin/pinned from @pa_iova. */ int pa_nr; }; @@ -53,14 +57,8 @@ struct ccwchain { * Attempt to pin user pages in memory. * * Usage of pfn_array: - * @pa->pa_iova starting guest physical I/O address. Assigned by caller. - * @pa->pa_iova_pfn array that stores PFNs of the pages need to pin. Allocated - * by caller. - * @pa->pa_pfn array that receives PFNs of the pages pinned. Allocated by - * caller. - * @pa->pa_nr number of pages from @pa->pa_iova to pin. Assigned by - * caller. - * number of pages pinned. Assigned by callee. + * Any field in this structure should be initialized by caller. + * We expect @pa->pa_nr > 0, and its value will be assigned by callee. * * Returns: * Number of pages pinned on success. |