From 2e8a6f89de69d149bde135c2dc89daa9127984a9 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Fri, 10 Oct 2008 22:39:36 +0200 Subject: ide-{floppy,tape}: remove packet command stack * Add 'struct ide_atapi_pc queued_pc' to struct ide_{floppy,tape}_obj and switch ide*_do_request() to use it (there can be only one active request for a given device). * Add 'struct ide_atapi_pc request_sense_pc' to struct ide_*_obj and switch ide*_retry_pc() to use it. * Remove needless {floppy,tape}->pc assignment from ide*_setup(). * Remove no longer needed ide*_next_pc_storage(), pc_stack[], rq_stack_index, IDE*_PC_STACK and DBG_PC_STACK. There should be no functional changes caused by this patch. Cc: Borislav Petkov Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ide/ide-tape.c | 48 ++++++------------------------------------------ 1 file changed, 6 insertions(+), 42 deletions(-) (limited to 'drivers/ide/ide-tape.c') diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c index dd3533505e3..ba05e03f482 100644 --- a/drivers/ide/ide-tape.c +++ b/drivers/ide/ide-tape.c @@ -56,8 +56,6 @@ enum { DBG_CHRDEV = (1 << 2), /* all remaining procedures */ DBG_PROCS = (1 << 3), - /* buffer alloc info (pc_stack) */ - DBG_PC_STACK = (1 << 4), }; /* define to see debug info */ @@ -88,13 +86,6 @@ enum { */ #define IDETAPE_PC_BUFFER_SIZE 256 -/* - * In various places in the driver, we need to allocate storage for packet - * commands, which will remain valid while we leave the driver to wait for - * an interrupt or a timeout event. - */ -#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES) - /* * Some drives (for example, Seagate STT3401A Travan) require a very long * timeout, because they don't return an interrupt or clear their busy bit @@ -208,13 +199,6 @@ typedef struct ide_tape_obj { struct kref kref; /* - * Since a typical character device operation requires more - * than one packet command, we provide here enough memory - * for the maximum of interconnected packet commands. - * The packet commands are stored in the circular array pc_stack. - * pc_stack_index points to the last used entry, and warps around - * to the start when we get to the last array entry. - * * pc points to the current processed packet command. * * failed_pc points to the last failed packet command, or contains @@ -226,11 +210,10 @@ typedef struct ide_tape_obj { struct ide_atapi_pc *pc; /* Last failed packet command */ struct ide_atapi_pc *failed_pc; - /* Packet command stack */ - struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK]; - /* Next free packet command storage space */ - int pc_stack_index; + /* used by REQ_IDETAPE_{READ,WRITE} requests */ + struct ide_atapi_pc queued_pc; + struct ide_atapi_pc request_sense_pc; struct request request_sense_rq; /* @@ -451,23 +434,6 @@ static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) pc->bh = bh; } -/* - * idetape_next_pc_storage returns a pointer to a place in which we can - * safely store a packet command, even though we intend to leave the - * driver. A storage space for a maximum of IDETAPE_PC_STACK packet - * commands is allocated at initialization time. - */ -static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive) -{ - idetape_tape_t *tape = drive->driver_data; - - debug_log(DBG_PC_STACK, "pc_stack_index=%d\n", tape->pc_stack_index); - - if (tape->pc_stack_index == IDETAPE_PC_STACK) - tape->pc_stack_index = 0; - return (&tape->pc_stack[tape->pc_stack_index++]); -} - /* * called on each failed packet command retry to analyze the request sense. We * currently do not utilize this information. @@ -693,10 +659,9 @@ static void idetape_retry_pc(ide_drive_t *drive) { struct ide_tape_obj *tape = drive->driver_data; struct request *rq = &tape->request_sense_rq; - struct ide_atapi_pc *pc; + struct ide_atapi_pc *pc = &tape->request_sense_pc; (void)ide_read_error(drive); - pc = idetape_next_pc_storage(drive); idetape_create_request_sense_cmd(pc); set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); idetape_queue_pc_head(drive, pc, rq); @@ -1006,12 +971,12 @@ static ide_startstop_t idetape_do_request(ide_drive_t *drive, return ide_stopped; } if (rq->cmd[13] & REQ_IDETAPE_READ) { - pc = idetape_next_pc_storage(drive); + pc = &tape->queued_pc; ide_tape_create_rw_cmd(tape, pc, rq, READ_6); goto out; } if (rq->cmd[13] & REQ_IDETAPE_WRITE) { - pc = idetape_next_pc_storage(drive); + pc = &tape->queued_pc; ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); goto out; } @@ -2412,7 +2377,6 @@ static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) tape->name[1] = 't'; tape->name[2] = '0' + minor; tape->chrdev_dir = IDETAPE_DIR_NONE; - tape->pc = tape->pc_stack; *((u16 *)&gcw) = drive->id[ATA_ID_CONFIG]; -- cgit v1.2.3