From 0aa4b01e0345bb43450dee4377fc53fb4fd44eb1 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 27 Apr 2008 15:38:27 +0200 Subject: [PATCH] ide-tape: remove remaining pipeline functionality The driver is using now solely its own request queue. - tape->next_stage is always NULL so it is safe to remove all code depending on tape->next_stage != NULL - this patch removes the last place which sets IDETAPE_FLAG_PIPELINE_ACTIVE in tape->flags [bart: add above explanations] Signed-off-by: Borislav Petkov Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ide/ide-tape.c | 102 +------------------------------------------------ 1 file changed, 2 insertions(+), 100 deletions(-) diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c index ad7e532cbe60..8eb117519ba4 100644 --- a/drivers/ide/ide-tape.c +++ b/drivers/ide/ide-tape.c @@ -642,28 +642,6 @@ static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) } } -static void idetape_activate_next_stage(ide_drive_t *drive) -{ - idetape_tape_t *tape = drive->driver_data; - idetape_stage_t *stage = tape->next_stage; - struct request *rq = &stage->rq; - - debug_log(DBG_PROCS, "Enter %s\n", __func__); - - if (stage == NULL) { - printk(KERN_ERR "ide-tape: bug: Trying to activate a non" - " existing stage\n"); - return; - } - - rq->rq_disk = tape->disk; - rq->buffer = NULL; - rq->special = (void *)stage->bh; - tape->active_data_rq = rq; - tape->active_stage = stage; - tape->next_stage = stage->next; -} - /* Free a stage along with its related buffers completely. */ static void __idetape_kfree_stage(idetape_stage_t *stage) { @@ -1546,28 +1524,6 @@ static void idetape_init_merge_stage(idetape_tape_t *tape) } } -/* Install a completion in a pending request and sleep until it is serviced. The - * caller should ensure that the request will not be serviced before we install - * the completion (usually by disabling interrupts). - */ -static void idetape_wait_for_request(ide_drive_t *drive, struct request *rq) -{ - DECLARE_COMPLETION_ONSTACK(wait); - idetape_tape_t *tape = drive->driver_data; - - if (rq == NULL || !blk_special_request(rq)) { - printk(KERN_ERR "ide-tape: bug: Trying to sleep on non-valid" - " request\n"); - return; - } - rq->end_io_data = &wait; - rq->end_io = blk_end_sync_rq; - spin_unlock_irq(&tape->lock); - wait_for_completion(&wait); - /* The stage and its struct request have been deallocated */ - spin_lock_irq(&tape->lock); -} - static ide_startstop_t idetape_read_position_callback(ide_drive_t *drive) { idetape_tape_t *tape = drive->driver_data; @@ -1782,8 +1738,6 @@ static int __idetape_discard_read_pipeline(ide_drive_t *drive) spin_lock_irqsave(&tape->lock, flags); tape->next_stage = NULL; - if (test_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, &tape->flags)) - idetape_wait_for_request(drive, tape->active_data_rq); spin_unlock_irqrestore(&tape->lock, flags); while (tape->first_stage != NULL) { @@ -1878,19 +1832,6 @@ static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, return (tape->blk_size * (blocks-rq.current_nr_sectors)); } -/* start servicing the pipeline stages, starting from tape->next_stage. */ -static void idetape_plug_pipeline(ide_drive_t *drive) -{ - idetape_tape_t *tape = drive->driver_data; - - if (tape->next_stage == NULL) - return; - if (!test_and_set_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, &tape->flags)) { - idetape_activate_next_stage(drive); - (void) ide_do_drive_cmd(drive, tape->active_data_rq, ide_end); - } -} - static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) { idetape_init_pc(pc); @@ -1932,45 +1873,11 @@ static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) { idetape_tape_t *tape = drive->driver_data; - unsigned long flags; debug_log(DBG_CHRDEV, "Enter %s\n", __func__); - /* Attempt to allocate a new stage. Beware possible race conditions. */ - while (1) { - spin_lock_irqsave(&tape->lock, flags); - if (test_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, &tape->flags)) { - idetape_wait_for_request(drive, tape->active_data_rq); - spin_unlock_irqrestore(&tape->lock, flags); - } else { - spin_unlock_irqrestore(&tape->lock, flags); - idetape_plug_pipeline(drive); - if (test_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, - &tape->flags)) - continue; - return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, - blocks, tape->merge_stage->bh); - } - } -} - -/* - * Wait until all pending pipeline requests are serviced. Typically called on - * device close. - */ -static void idetape_wait_for_pipeline(ide_drive_t *drive) -{ - idetape_tape_t *tape = drive->driver_data; - unsigned long flags; - - while (tape->next_stage || test_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, - &tape->flags)) { - idetape_plug_pipeline(drive); - spin_lock_irqsave(&tape->lock, flags); - if (test_bit(IDETAPE_FLAG_PIPELINE_ACTIVE, &tape->flags)) - idetape_wait_for_request(drive, tape->active_data_rq); - spin_unlock_irqrestore(&tape->lock, flags); - } + return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, + blocks, tape->merge_stage->bh); } static void idetape_empty_write_pipeline(ide_drive_t *drive) @@ -2020,7 +1927,6 @@ static void idetape_empty_write_pipeline(ide_drive_t *drive) (void) idetape_add_chrdev_write_request(drive, blocks); tape->merge_stage_size = 0; } - idetape_wait_for_pipeline(drive); if (tape->merge_stage != NULL) { __idetape_kfree_stage(tape->merge_stage); tape->merge_stage = NULL; @@ -2093,7 +1999,6 @@ static int idetape_init_read(ide_drive_t *drive, int max_stages) tape->insert_time = jiffies; tape->insert_size = 0; tape->insert_speed = 0; - idetape_plug_pipeline(drive); } } return 0; @@ -2593,7 +2498,6 @@ static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, idetape_flush_tape_buffers(drive); } if (cmd == MTIOCGET || cmd == MTIOCPOS) { - idetape_wait_for_pipeline(drive); block_offset = tape->merge_stage_size / (tape->blk_size * tape->user_bs_factor); position = idetape_read_position(drive); @@ -2772,8 +2676,6 @@ static int idetape_chrdev_release(struct inode *inode, struct file *filp) if (tape->chrdev_dir == IDETAPE_DIR_READ) { if (minor < 128) idetape_discard_read_pipeline(drive, 1); - else - idetape_wait_for_pipeline(drive); } if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags)) -- 2.11.0