From d93bc4521c80e9d87767779814e88f6d725453d7 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Tue, 31 Mar 2009 20:15:26 +0200 Subject: [PATCH] ide-{floppy,tape}: fix padding for PIO transfers * Return number of bytes left to transfer from idetape_{in,out}put_buffers() and number of bytes done from ide_tape_io_buffers(). * Fix padding for PIO transfers in ide_pc_intr() so read/write buffers are always completely processed and then the transfer is padded if necessary. * Remove invalid error messages. * Remove now superfluous padding from ide{_io_buffers,tape_input_buffers}(). While at it: * Set pc->bh to NULL in idetape_input_buffers() after all bh-s are done. * Cache !!(pc->flags & PC_FLAG_WRITING) in local variable in ide_pc_intr(). Cc: Borislav Petkov Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ide/ide-atapi.c | 57 +++++++++++++++++-------------------------------- drivers/ide/ide-tape.c | 32 +++++++++++++-------------- 2 files changed, 35 insertions(+), 54 deletions(-) diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 3f3fc7c..40f413b 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -110,13 +110,6 @@ int ide_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, } } - if (bcount) { - printk(KERN_ERR "%s: %d leftover bytes, %s\n", drive->name, - bcount, write ? "padding with zeros" - : "discarding data"); - ide_pad_transfer(drive, write, bcount); - } - return done; } EXPORT_SYMBOL_GPL(ide_io_buffers); @@ -330,9 +323,10 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) struct request *rq = hwif->rq; const struct ide_tp_ops *tp_ops = hwif->tp_ops; xfer_func_t *xferfunc; - unsigned int timeout, temp; + unsigned int timeout, done; u16 bcount; u8 stat, ireason, dsc = 0; + u8 write = !!(pc->flags & PC_FLAG_WRITING); debug_log("Enter %s - interrupt handler\n", __func__); @@ -441,8 +435,7 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) return ide_do_reset(drive); } - if (((ireason & ATAPI_IO) == ATAPI_IO) == - !!(pc->flags & PC_FLAG_WRITING)) { + if (((ireason & ATAPI_IO) == ATAPI_IO) == write) { /* Hopefully, we will never get here */ printk(KERN_ERR "%s: We wanted to %s, but the device wants us " "to %s!\n", drive->name, @@ -451,45 +444,33 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) return ide_do_reset(drive); } - if (!(pc->flags & PC_FLAG_WRITING)) { - /* Reading - Check that we have enough space */ - temp = pc->xferred + bcount; - if (temp > pc->req_xfer) { - if (temp > pc->buf_size) { - printk(KERN_ERR "%s: The device wants to send " - "us more data than expected - " - "discarding data\n", - drive->name); - - ide_pad_transfer(drive, 0, bcount); - goto next_irq; - } - debug_log("The device wants to send us more data than " - "expected - allowing transfer\n"); - } - xferfunc = tp_ops->input_data; - } else - xferfunc = tp_ops->output_data; + xferfunc = write ? tp_ops->output_data : tp_ops->input_data; if ((drive->media == ide_floppy && !pc->buf) || (drive->media == ide_tape && pc->bh)) { - int done = drive->pc_io_buffers(drive, pc, bcount, - !!(pc->flags & PC_FLAG_WRITING)); + done = drive->pc_io_buffers(drive, pc, bcount, write); /* FIXME: don't do partial completions */ if (drive->media == ide_floppy) ide_complete_rq(drive, 0, done ? done : ide_rq_bytes(rq)); - } else - xferfunc(drive, NULL, pc->cur_pos, bcount); + } else { + done = min_t(unsigned int, bcount, pc->req_xfer - pc->xferred); + xferfunc(drive, NULL, pc->cur_pos, done); + } /* Update the current position */ - pc->xferred += bcount; - pc->cur_pos += bcount; + pc->xferred += done; + pc->cur_pos += done; + + bcount -= done; + + if (bcount) + ide_pad_transfer(drive, write, bcount); + + debug_log("[cmd %x] transferred %d bytes, padded %d bytes\n", + rq->cmd[0], done, bcount); - debug_log("[cmd %x] transferred %d bytes on that intr.\n", - rq->cmd[0], bcount); -next_irq: /* And set the interrupt handler again */ ide_set_handler(drive, ide_pc_intr, timeout); return ide_started; diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c index cafc67d..cb942a9 100644 --- a/drivers/ide/ide-tape.c +++ b/drivers/ide/ide-tape.c @@ -297,19 +297,15 @@ static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) return tape; } -static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, +static int idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount) { struct idetape_bh *bh = pc->bh; int count; while (bcount) { - if (bh == NULL) { - printk(KERN_ERR "ide-tape: bh == NULL in " - "idetape_input_buffers\n"); - ide_pad_transfer(drive, 0, bcount); - return; - } + if (bh == NULL) + break; count = min( (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount); @@ -323,21 +319,21 @@ static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, atomic_set(&bh->b_count, 0); } } + pc->bh = bh; + + return bcount; } -static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, +static int idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount) { struct idetape_bh *bh = pc->bh; int count; while (bcount) { - if (bh == NULL) { - printk(KERN_ERR "ide-tape: bh == NULL in %s\n", - __func__); - return; - } + if (bh == NULL) + break; count = min((unsigned int)pc->b_count, (unsigned int)bcount); drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); bcount -= count; @@ -352,6 +348,8 @@ static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, } } } + + return bcount; } static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) @@ -563,12 +561,14 @@ static void ide_tape_handle_dsc(ide_drive_t *drive) static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount, int write) { + unsigned int bleft; + if (write) - idetape_output_buffers(drive, pc, bcount); + bleft = idetape_output_buffers(drive, pc, bcount); else - idetape_input_buffers(drive, pc, bcount); + bleft = idetape_input_buffers(drive, pc, bcount); - return bcount; + return bcount - bleft; } /* -- 2.7.4