diff options
Diffstat (limited to 'arch/s390/include/asm/ap.h')
| -rw-r--r-- | arch/s390/include/asm/ap.h | 48 |
1 files changed, 41 insertions, 7 deletions
diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h index 837d1699b109..5e77a81ab36a 100644 --- a/arch/s390/include/asm/ap.h +++ b/arch/s390/include/asm/ap.h @@ -325,6 +325,8 @@ static inline struct ap_queue_status ap_nqap(ap_qid_t qid, * @psmid: Pointer to program supplied message identifier * @msg: The message text * @length: The message length + * @reslength: Resitual length on return + * @resgr0: input: gr0 value (only used if != 0), output: resitual gr0 content * * Returns AP queue status structure. * Condition code 1 on DQAP means the receive has taken place @@ -336,12 +338,25 @@ static inline struct ap_queue_status ap_nqap(ap_qid_t qid, * Note that gpr2 is used by the DQAP instruction to keep track of * any 'residual' length, in case the instruction gets interrupted. * Hence it gets zeroed before the instruction. + * If the message does not fit into the buffer, this function will + * return with a truncated message and the reply in the firmware queue + * is not removed. This is indicated to the caller with an + * ap_queue_status response_code value of all bits on (0xFF) and (if + * the reslength ptr is given) the remaining length is stored in + * *reslength and (if the resgr0 ptr is given) the updated gr0 value + * for further processing of this msg entry is stored in *resgr0. The + * caller needs to detect this situation and should invoke ap_dqap + * with a valid resgr0 ptr and a value in there != 0 to indicate that + * *resgr0 is to be used instead of qid to further process this entry. */ static inline struct ap_queue_status ap_dqap(ap_qid_t qid, unsigned long long *psmid, - void *msg, size_t length) + void *msg, size_t length, + size_t *reslength, + unsigned long *resgr0) { - register unsigned long reg0 asm("0") = qid | 0x80000000UL; + register unsigned long reg0 asm("0") = + resgr0 && *resgr0 ? *resgr0 : qid | 0x80000000UL; register struct ap_queue_status reg1 asm ("1"); register unsigned long reg2 asm("2") = 0UL; register unsigned long reg4 asm("4") = (unsigned long) msg; @@ -349,14 +364,33 @@ static inline struct ap_queue_status ap_dqap(ap_qid_t qid, register unsigned long reg6 asm("6") = 0UL; register unsigned long reg7 asm("7") = 0UL; - asm volatile( - "0: .long 0xb2ae0064\n" /* DQAP */ - " brc 6,0b\n" + "0: ltgr %[bl],%[bl]\n" /* if avail. buf len is 0 then */ + " jz 2f\n" /* go out of this asm block */ + "1: .long 0xb2ae0064\n" /* DQAP */ + " brc 6,0b\n" /* if partially do again */ + "2:\n" : "+d" (reg0), "=d" (reg1), "+d" (reg2), - "+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7) + "+d" (reg4), [bl] "+d" (reg5), "+d" (reg6), "+d" (reg7) : : "cc", "memory"); - *psmid = (((unsigned long long) reg6) << 32) + reg7; + + if (reslength) + *reslength = reg2; + if (reg2 != 0 && reg5 == 0) { + /* + * Partially complete, status in gr1 is not set. + * Signal the caller that this dqap is only partially received + * with a special status response code 0xFF and *resgr0 updated + */ + reg1.response_code = 0xFF; + if (resgr0) + *resgr0 = reg0; + } else { + *psmid = (((unsigned long long) reg6) << 32) + reg7; + if (resgr0) + *resgr0 = 0; + } + return reg1; } |