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Diffstat (limited to 'drivers/ide/ide-tape.c')
-rw-r--r--drivers/ide/ide-tape.c68
1 files changed, 12 insertions, 56 deletions
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 83014abf330f..dd3533505e3b 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -56,8 +56,8 @@ enum {
56 DBG_CHRDEV = (1 << 2), 56 DBG_CHRDEV = (1 << 2),
57 /* all remaining procedures */ 57 /* all remaining procedures */
58 DBG_PROCS = (1 << 3), 58 DBG_PROCS = (1 << 3),
59 /* buffer alloc info (pc_stack & rq_stack) */ 59 /* buffer alloc info (pc_stack) */
60 DBG_PCRQ_STACK = (1 << 4), 60 DBG_PC_STACK = (1 << 4),
61}; 61};
62 62
63/* define to see debug info */ 63/* define to see debug info */
@@ -89,9 +89,9 @@ enum {
89#define IDETAPE_PC_BUFFER_SIZE 256 89#define IDETAPE_PC_BUFFER_SIZE 256
90 90
91/* 91/*
92 * In various places in the driver, we need to allocate storage 92 * In various places in the driver, we need to allocate storage for packet
93 * for packet commands and requests, which will remain valid while 93 * commands, which will remain valid while we leave the driver to wait for
94 * we leave the driver to wait for an interrupt or a timeout event. 94 * an interrupt or a timeout event.
95 */ 95 */
96#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES) 96#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
97 97
@@ -230,9 +230,8 @@ typedef struct ide_tape_obj {
230 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK]; 230 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
231 /* Next free packet command storage space */ 231 /* Next free packet command storage space */
232 int pc_stack_index; 232 int pc_stack_index;
233 struct request rq_stack[IDETAPE_PC_STACK]; 233
234 /* We implement a circular array */ 234 struct request request_sense_rq;
235 int rq_stack_index;
236 235
237 /* 236 /*
238 * DSC polling variables. 237 * DSC polling variables.
@@ -462,7 +461,7 @@ static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
462{ 461{
463 idetape_tape_t *tape = drive->driver_data; 462 idetape_tape_t *tape = drive->driver_data;
464 463
465 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index); 464 debug_log(DBG_PC_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
466 465
467 if (tape->pc_stack_index == IDETAPE_PC_STACK) 466 if (tape->pc_stack_index == IDETAPE_PC_STACK)
468 tape->pc_stack_index = 0; 467 tape->pc_stack_index = 0;
@@ -470,30 +469,6 @@ static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
470} 469}
471 470
472/* 471/*
473 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
474 * Since we queue packet commands in the request queue, we need to
475 * allocate a request, along with the allocation of a packet command.
476 */
477
478/**************************************************************
479 * *
480 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
481 * followed later on by kfree(). -ml *
482 * *
483 **************************************************************/
484
485static struct request *idetape_next_rq_storage(ide_drive_t *drive)
486{
487 idetape_tape_t *tape = drive->driver_data;
488
489 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
490
491 if (tape->rq_stack_index == IDETAPE_PC_STACK)
492 tape->rq_stack_index = 0;
493 return (&tape->rq_stack[tape->rq_stack_index++]);
494}
495
496/*
497 * called on each failed packet command retry to analyze the request sense. We 472 * called on each failed packet command retry to analyze the request sense. We
498 * currently do not utilize this information. 473 * currently do not utilize this information.
499 */ 474 */
@@ -692,17 +667,7 @@ static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
692/* 667/*
693 * Generate a new packet command request in front of the request queue, before 668 * Generate a new packet command request in front of the request queue, before
694 * the current request, so that it will be processed immediately, on the next 669 * the current request, so that it will be processed immediately, on the next
695 * pass through the driver. The function below is called from the request 670 * pass through the driver.
696 * handling part of the driver (the "bottom" part). Safe storage for the request
697 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
698 *
699 * Memory for those requests is pre-allocated at initialization time, and is
700 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
701 * the maximum possible number of inter-dependent packet commands.
702 *
703 * The higher level of the driver - The ioctl handler and the character device
704 * handling functions should queue request to the lower level part and wait for
705 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
706 */ 671 */
707static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc, 672static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
708 struct request *rq) 673 struct request *rq)
@@ -726,12 +691,12 @@ static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
726 */ 691 */
727static void idetape_retry_pc(ide_drive_t *drive) 692static void idetape_retry_pc(ide_drive_t *drive)
728{ 693{
694 struct ide_tape_obj *tape = drive->driver_data;
695 struct request *rq = &tape->request_sense_rq;
729 struct ide_atapi_pc *pc; 696 struct ide_atapi_pc *pc;
730 struct request *rq;
731 697
732 (void)ide_read_error(drive); 698 (void)ide_read_error(drive);
733 pc = idetape_next_pc_storage(drive); 699 pc = idetape_next_pc_storage(drive);
734 rq = idetape_next_rq_storage(drive);
735 idetape_create_request_sense_cmd(pc); 700 idetape_create_request_sense_cmd(pc);
736 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 701 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
737 idetape_queue_pc_head(drive, pc, rq); 702 idetape_queue_pc_head(drive, pc, rq);
@@ -1247,16 +1212,7 @@ static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1247 1212
1248/* 1213/*
1249 * We add a special packet command request to the tail of the request queue, and 1214 * We add a special packet command request to the tail of the request queue, and
1250 * wait for it to be serviced. This is not to be called from within the request 1215 * wait for it to be serviced.
1251 * handling part of the driver! We allocate here data on the stack and it is
1252 * valid until the request is finished. This is not the case for the bottom part
1253 * of the driver, where we are always leaving the functions to wait for an
1254 * interrupt or a timer event.
1255 *
1256 * From the bottom part of the driver, we should allocate safe memory using
1257 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1258 * to the request list without waiting for it to be serviced! In that case, we
1259 * usually use idetape_queue_pc_head().
1260 */ 1216 */
1261static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc) 1217static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1262{ 1218{