diff options
Diffstat (limited to 'drivers/staging/unisys/visornic')
| -rw-r--r-- | drivers/staging/unisys/visornic/visornic_main.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/staging/unisys/visornic/visornic_main.c b/drivers/staging/unisys/visornic/visornic_main.c index b961d7e1ae7b..89de87fa9e4d 100644 --- a/drivers/staging/unisys/visornic/visornic_main.c +++ b/drivers/staging/unisys/visornic/visornic_main.c @@ -141,6 +141,43 @@ struct visornic_devdata { struct uiscmdrsp cmdrsp[SIZEOF_CMDRSP]; }; +/* Returns next non-zero index on success or 0 on failure (i.e. out of room). */ +static inline u16 +add_physinfo_entries(u64 inp_pfn, u16 inp_off, u32 inp_len, u16 index, + u16 max_pi_arr_entries, struct phys_info pi_arr[]) +{ + u32 len; + u16 i, firstlen; + + firstlen = PI_PAGE_SIZE - inp_off; + if (inp_len <= firstlen) { + /* The input entry spans only one page - add as is. */ + if (index >= max_pi_arr_entries) + return 0; + pi_arr[index].pi_pfn = inp_pfn; + pi_arr[index].pi_off = (u16)inp_off; + pi_arr[index].pi_len = (u16)inp_len; + return index + 1; + } + + /* This entry spans multiple pages. */ + for (len = inp_len, i = 0; len; + len -= pi_arr[index + i].pi_len, i++) { + if (index + i >= max_pi_arr_entries) + return 0; + pi_arr[index + i].pi_pfn = inp_pfn + i; + if (i == 0) { + pi_arr[index].pi_off = inp_off; + pi_arr[index].pi_len = firstlen; + } else { + pi_arr[index + i].pi_off = 0; + pi_arr[index + i].pi_len = + (u16)MINNUM(len, (u32)PI_PAGE_SIZE); + } + } + return index + i; +} + /* * visor_copy_fragsinfo_from_skb( * @skb_in: skbuff that we are pulling the frags from |