[PATCH][CFT] IDE TCQ #2

From: Jens Axboe (axboe@suse.de)
Date: Tue Apr 09 2002 - 07:44:17 EST


Hi,

Version 2 is ready. Changes since last time:

- Check if we are using TCQ before doing BUG() if we encounter a
  plugged queue in ide_do_request(). If so, we just need to quit.
  SMP race posted yesterday.

- Clean /proc/ide/hdX/tcq output

- Add queue depth controls in /proc/ide/hdX/setting:

  echo "using_tcq:0" > /proc/ide/hdX/setting

  will disable TCQ and revert to DMA,

  echo "using_tcq:32" > /proc/ide/hdX/setting

  will set queue depth to 32, any value in between the two are of course
  also allowed. The driver will print enable/disable info to the kernel
  log.

- Include the get_request() starvation from akpm, bump queue size a bit
  as well.

- Correctly use other depths that none or full.

- Make the current depth and int not atomic_t, access is serialized to
  it.

- Remove 'unexpected interrupt' warnings at boot

- Cleanup service and interrupt handling

- Make the initial tcq enable much nicer

This make look like a lot of stuff, but the only real bug fixed is the
SMP race mentioned yesterday. Rest is just features and cleanup. The
code has taken quite a lot of beating, so I'm ready to call this beta
and ask for more testers. No malfunctions have been detected here. Stuff
to still look out for:

- Don't enable TCQ on both master/slave on a channel! That mode is not
  supported yet, only enable TCQ on one of them at the time.

- SMP seems to have minor performance regression, performance testing
  should be UP only for now. Also note that I haven't really done any
  performance testing yet, just data integrity and stability work.

Enjoy!

diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/block/ll_rw_blk.c linux/drivers/block/ll_rw_blk.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/block/ll_rw_blk.c Mon Mar 18 21:37:05 2002
+++ linux/drivers/block/ll_rw_blk.c Tue Apr 9 10:35:20 2002
@@ -857,10 +857,10 @@
         spin_lock_prefetch(q->queue_lock);
 
         generic_unplug_device(q);
- add_wait_queue(&rl->wait, &wait);
+ add_wait_queue_exclusive(&rl->wait, &wait);
         do {
                 set_current_state(TASK_UNINTERRUPTIBLE);
- if (rl->count < batch_requests)
+ if (!rl->count)
                         schedule();
                 spin_lock_irq(q->queue_lock);
                 rq = get_request(q, rw);
@@ -1683,9 +1683,11 @@
          * Free request slots per queue.
          * (Half for reads, half for writes)
          */
- queue_nr_requests = 64;
- if (total_ram > MB(32))
- queue_nr_requests = 256;
+ queue_nr_requests = (total_ram >> 8) & ~15; /* One per quarter-megabyte */
+ if (queue_nr_requests < 32)
+ queue_nr_requests = 32;
+ if (queue_nr_requests > 256)
+ queue_nr_requests = 256;
 
         /*
          * Batch frees according to queue length
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/Config.help linux/drivers/ide/Config.help
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/Config.help Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/Config.help Mon Apr 8 13:27:12 2002
@@ -744,6 +744,28 @@
 
   Generally say N here.
 
+CONFIG_BLK_DEV_IDE_TCQ
+ Support for tagged command queueing on ATA disk drives. This enables
+ the IDE layer to have multiple in-flight requests on hardware that
+ supports it. For now this includes the IBM Deskstar series drives,
+ such as the GXP75, 40GV, GXP60, and GXP120 (ie any Deskstar made in
+ the last couple of years).
+
+ If you have such a drive, say Y here.
+
+CONFIG_BLK_DEV_IDE_TCQ_DEFAULT
+ Enabled tagged command queueing unconditionally on drives that report
+ support for it.
+
+ Generally say Y here.
+
+CONFIG_BLK_DEV_IDE_TCQ_DEPTH
+ Maximum size of commands to enable per-drive. Any value between 1
+ and 32 is valid, with 32 being the maxium that the hardware supports.
+
+ You probably just want the default of 32 here. If you enter an invalid
+ number, the default value will be used.
+
 CONFIG_BLK_DEV_IT8172
   Say Y here to support the on-board IDE controller on the Integrated
   Technology Express, Inc. ITE8172 SBC. Vendor page at
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/Config.in linux/drivers/ide/Config.in
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/Config.in Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/Config.in Tue Apr 2 09:03:38 2002
@@ -47,6 +47,11 @@
          dep_bool ' Use PCI DMA by default when available' CONFIG_IDEDMA_PCI_AUTO $CONFIG_BLK_DEV_IDEDMA_PCI
          dep_bool ' Enable DMA only for disks ' CONFIG_IDEDMA_ONLYDISK $CONFIG_IDEDMA_PCI_AUTO
          define_bool CONFIG_BLK_DEV_IDEDMA $CONFIG_BLK_DEV_IDEDMA_PCI
+ dep_bool ' IDE tagged command queueing' CONFIG_BLK_DEV_IDE_TCQ $CONFIG_BLK_DEV_IDEDMA_PCI
+ dep_bool ' TCQ on by default' CONFIG_BLK_DEV_IDE_TCQ_DEFAULT $CONFIG_BLK_DEV_IDE_TCQ
+ if [ $CONFIG_BLK_DEV_IDE_TCQ_DEFAULT != "n" ]; then
+ int ' Default queue depth' CONFIG_BLK_DEV_IDE_TCQ_DEPTH 32
+ fi
          dep_bool ' ATA Work(s) In Progress (EXPERIMENTAL)' CONFIG_IDEDMA_PCI_WIP $CONFIG_BLK_DEV_IDEDMA_PCI $CONFIG_EXPERIMENTAL
          dep_bool ' Good-Bad DMA Model-Firmware (WIP)' CONFIG_IDEDMA_NEW_DRIVE_LISTINGS $CONFIG_IDEDMA_PCI_WIP
          dep_bool ' AEC62XX chipset support' CONFIG_BLK_DEV_AEC62XX $CONFIG_BLK_DEV_IDEDMA_PCI
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/Makefile linux/drivers/ide/Makefile
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/Makefile Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/Makefile Tue Apr 2 09:03:38 2002
@@ -45,6 +45,7 @@
 ide-obj-$(CONFIG_BLK_DEV_HT6560B) += ht6560b.o
 ide-obj-$(CONFIG_BLK_DEV_IDE_ICSIDE) += icside.o
 ide-obj-$(CONFIG_BLK_DEV_IDEDMA_PCI) += ide-dma.o
+ide-obj-$(CONFIG_BLK_DEV_IDE_TCQ) += ide-tcq.o
 ide-obj-$(CONFIG_BLK_DEV_IDEPCI) += ide-pci.o
 ide-obj-$(CONFIG_BLK_DEV_ISAPNP) += ide-pnp.o
 ide-obj-$(CONFIG_BLK_DEV_IDE_PMAC) += ide-pmac.o
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-disk.c linux/drivers/ide/ide-disk.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-disk.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide-disk.c Tue Apr 9 10:29:46 2002
@@ -26,9 +26,10 @@
  * Version 1.11 Highmem I/O support, Jens Axboe <axboe@suse.de>
  * Version 1.12 added 48-bit lba
  * Version 1.13 adding taskfile io access method
+ * Version 1.14 Added tcq support, Jens Axboe <axboe@suse.de>
  */
 
-#define IDEDISK_VERSION "1.13"
+#define IDEDISK_VERSION "1.14"
 
 #include <linux/config.h>
 #include <linux/module.h>
@@ -109,53 +110,64 @@
 static u8 get_command(ide_drive_t *drive, int cmd)
 {
         int lba48bit = (drive->id->cfs_enable_2 & 0x0400) ? 1 : 0;
+ int command = WIN_NOP;
 
 #if 1
         lba48bit = drive->addressing;
 #endif
 
+ /*
+ * 48-bit commands are pretty sanely laid out
+ */
         if (lba48bit) {
- if (cmd == READ) {
- if (drive->using_dma)
- return WIN_READDMA_EXT;
- else if (drive->mult_count)
- return WIN_MULTREAD_EXT;
- else
- return WIN_READ_EXT;
- } else if (cmd == WRITE) {
- if (drive->using_dma)
- return WIN_WRITEDMA_EXT;
- else if (drive->mult_count)
- return WIN_MULTWRITE_EXT;
- else
- return WIN_WRITE_EXT;
- }
+ if (cmd == READ)
+ command = WIN_READ_EXT;
+ else
+ command = WIN_WRITE_EXT;
+
+ if (drive->using_dma) {
+ command++; /* WIN_*DMA_EXT */
+ if (drive->using_tcq)
+ command++; /* WIN_*DMA_QUEUED_EXT */
+ } else if (drive->mult_count)
+ command += 5; /* WIN_MULT*_EXT */
         } else {
+ /*
+ * 28-bit commands seem not to be, though...
+ */
                 if (cmd == READ) {
- if (drive->using_dma)
- return WIN_READDMA;
- else if (drive->mult_count)
- return WIN_MULTREAD;
+ if (drive->using_dma) {
+ if (drive->using_tcq)
+ command = WIN_READDMA_QUEUED;
+ else
+ command = WIN_READDMA;
+ } else if (drive->mult_count)
+ command = WIN_MULTREAD;
                         else
- return WIN_READ;
- } else if (cmd == WRITE) {
- if (drive->using_dma)
- return WIN_WRITEDMA;
- else if (drive->mult_count)
- return WIN_MULTWRITE;
+ command = WIN_READ;
+ } else {
+ if (drive->using_dma) {
+ if (drive->using_tcq)
+ command = WIN_WRITEDMA_QUEUED;
+ else
+ command = WIN_WRITEDMA;
+ } else if (drive->mult_count)
+ command = WIN_MULTWRITE;
                         else
- return WIN_WRITE;
+ command = WIN_WRITE;
                 }
         }
- return WIN_NOP;
+
+ return command;
 }
 
-static ide_startstop_t chs_do_request(ide_drive_t *drive, struct request *rq, unsigned long block)
+static ide_startstop_t chs_do_request(ide_drive_t *drive, ata_request_t *ar, sector_t block)
 {
         struct hd_drive_task_hdr taskfile;
         struct hd_drive_hob_hdr hobfile;
- ide_task_t args;
- int sectors;
+ ide_task_t *args = &ar->ar_task;
+ struct request *rq = ar->ar_rq;
+ int sectors = rq->nr_sectors;
 
         unsigned int track = (block / drive->sect);
         unsigned int sect = (block % drive->sect) + 1;
@@ -165,11 +177,20 @@
         memset(&taskfile, 0, sizeof(struct hd_drive_task_hdr));
         memset(&hobfile, 0, sizeof(struct hd_drive_hob_hdr));
 
- sectors = rq->nr_sectors;
         if (sectors == 256)
                 sectors = 0;
 
- taskfile.sector_count = sectors;
+ if (ar->ar_flags & ATA_AR_QUEUED) {
+ unsigned long flags;
+
+ taskfile.feature = sectors;
+ taskfile.sector_count = ar->ar_tag << 3;
+
+ spin_lock_irqsave(DRIVE_LOCK(drive), flags);
+ blkdev_dequeue_request(rq);
+ spin_unlock_irqrestore(DRIVE_LOCK(drive), flags);
+ } else
+ taskfile.sector_count = sectors;
 
         taskfile.sector_number = sect;
         taskfile.low_cylinder = cyl;
@@ -177,45 +198,57 @@
 
         taskfile.device_head = head;
         taskfile.device_head |= drive->select.all;
- taskfile.command = get_command(drive, rq_data_dir(rq));
+ taskfile.command = get_command(drive, rq_data_dir(rq));
 
 #ifdef DEBUG
         printk("%s: %sing: ", drive->name,
                 (rq_data_dir(rq)==READ) ? "read" : "writ");
- if (lba) printk("LBAsect=%lld, ", block);
- else printk("CHS=%d/%d/%d, ", cyl, head, sect);
         printk("sectors=%ld, ", rq->nr_sectors);
+ printk("CHS=%d/%d/%d, ", cyl, head, sect);
         printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
 #endif
 
- args.taskfile = taskfile;
- args.hobfile = hobfile;
- ide_cmd_type_parser(&args);
- rq->special = &args;
+ memcpy(&args->taskfile, &taskfile, sizeof(struct hd_drive_task_hdr));
+ memcpy(&args->hobfile, &hobfile, sizeof(struct hd_drive_hob_hdr));
+ ide_cmd_type_parser(args);
+
+ args->ar = ar;
+ rq->special = ar;
 
         return ata_taskfile(drive,
- &args.taskfile,
- &args.hobfile,
- args.handler,
- args.prehandler,
+ &args->taskfile,
+ &args->hobfile,
+ args->handler,
+ args->prehandler,
                         rq);
 }
 
-static ide_startstop_t lba28_do_request(ide_drive_t *drive, struct request *rq, unsigned long block)
+static ide_startstop_t lba28_do_request(ide_drive_t *drive, ata_request_t *ar, sector_t block)
 {
         struct hd_drive_task_hdr taskfile;
         struct hd_drive_hob_hdr hobfile;
- ide_task_t args;
- int sectors;
+ ide_task_t *args = &ar->ar_task;
+ struct request *rq = ar->ar_rq;
+ int sectors = rq->nr_sectors;
 
- sectors = rq->nr_sectors;
         if (sectors == 256)
                 sectors = 0;
 
         memset(&taskfile, 0, sizeof(struct hd_drive_task_hdr));
         memset(&hobfile, 0, sizeof(struct hd_drive_hob_hdr));
 
- taskfile.sector_count = sectors;
+ if (ar->ar_flags & ATA_AR_QUEUED) {
+ unsigned long flags;
+
+ taskfile.feature = sectors;
+ taskfile.sector_count = ar->ar_tag << 3;
+
+ spin_lock_irqsave(DRIVE_LOCK(drive), flags);
+ blkdev_dequeue_request(rq);
+ spin_unlock_irqrestore(DRIVE_LOCK(drive), flags);
+ } else
+ taskfile.sector_count = sectors;
+
         taskfile.sector_number = block;
         taskfile.low_cylinder = (block >>= 8);
 
@@ -228,22 +261,21 @@
 #ifdef DEBUG
         printk("%s: %sing: ", drive->name,
                 (rq_data_dir(rq)==READ) ? "read" : "writ");
- if (lba) printk("LBAsect=%lld, ", block);
- else printk("CHS=%d/%d/%d, ", cyl, head, sect);
- printk("sectors=%ld, ", rq->nr_sectors);
+ printk("sector=%lx, sectors=%ld, ", block, rq->nr_sectors);
         printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
 #endif
 
- args.taskfile = taskfile;
- args.hobfile = hobfile;
- ide_cmd_type_parser(&args);
- rq->special = &args;
+ memcpy(&args->taskfile, &taskfile, sizeof(struct hd_drive_task_hdr));
+ memcpy(&args->hobfile, &hobfile, sizeof(struct hd_drive_hob_hdr));
+ ide_cmd_type_parser(args);
+ args->ar = ar;
+ rq->special = ar;
 
         return ata_taskfile(drive,
- &args.taskfile,
- &args.hobfile,
- args.handler,
- args.prehandler,
+ &args->taskfile,
+ &args->hobfile,
+ args->handler,
+ args->prehandler,
                         rq);
 }
 
@@ -253,26 +285,33 @@
  * 1073741822 == 549756 MB or 48bit addressing fake drive
  */
 
-static ide_startstop_t lba48_do_request(ide_drive_t *drive, struct request *rq, unsigned long long block)
+static ide_startstop_t lba48_do_request(ide_drive_t *drive, ata_request_t *ar, sector_t block)
 {
         struct hd_drive_task_hdr taskfile;
         struct hd_drive_hob_hdr hobfile;
- ide_task_t args;
- int sectors;
+ ide_task_t *args = &ar->ar_task;
+ struct request *rq = ar->ar_rq;
+ int sectors = rq->nr_sectors;
 
         memset(&taskfile, 0, sizeof(struct hd_drive_task_hdr));
         memset(&hobfile, 0, sizeof(struct hd_drive_hob_hdr));
 
- sectors = rq->nr_sectors;
         if (sectors == 65536)
                 sectors = 0;
 
- taskfile.sector_count = sectors;
- hobfile.sector_count = sectors >> 8;
+ if (ar->ar_flags & ATA_AR_QUEUED) {
+ unsigned long flags;
 
- if (rq->nr_sectors == 65536) {
- taskfile.sector_count = 0x00;
- hobfile.sector_count = 0x00;
+ taskfile.feature = sectors;
+ hobfile.feature = sectors >> 8;
+ taskfile.sector_count = ar->ar_tag << 3;
+
+ spin_lock_irqsave(DRIVE_LOCK(drive), flags);
+ blkdev_dequeue_request(rq);
+ spin_unlock_irqrestore(DRIVE_LOCK(drive), flags);
+ } else {
+ taskfile.sector_count = sectors;
+ hobfile.sector_count = sectors >> 8;
         }
 
         taskfile.sector_number = block; /* low lba */
@@ -291,22 +330,21 @@
 #ifdef DEBUG
         printk("%s: %sing: ", drive->name,
                 (rq_data_dir(rq)==READ) ? "read" : "writ");
- if (lba) printk("LBAsect=%lld, ", block);
- else printk("CHS=%d/%d/%d, ", cyl, head, sect);
- printk("sectors=%ld, ", rq->nr_sectors);
+ printk("sector=%lx, sectors=%ld, ", block, rq->nr_sectors);
         printk("buffer=0x%08lx\n", (unsigned long) rq->buffer);
 #endif
 
- args.taskfile = taskfile;
- args.hobfile = hobfile;
- ide_cmd_type_parser(&args);
- rq->special = &args;
+ memcpy(&args->taskfile, &taskfile, sizeof(struct hd_drive_task_hdr));
+ memcpy(&args->taskfile, &hobfile, sizeof(struct hd_drive_hob_hdr));
+ ide_cmd_type_parser(args);
+ args->ar = ar;
+ rq->special = ar;
 
         return ata_taskfile(drive,
- &args.taskfile,
- &args.hobfile,
- args.handler,
- args.prehandler,
+ &args->taskfile,
+ &args->hobfile,
+ args->handler,
+ args->prehandler,
                         rq);
 }
 
@@ -315,8 +353,11 @@
  * otherwise, to address sectors. It also takes care of issuing special
  * DRIVE_CMDs.
  */
-static ide_startstop_t idedisk_do_request(ide_drive_t *drive, struct request *rq, unsigned long block)
+static ide_startstop_t idedisk_do_request(ide_drive_t *drive, struct request *rq, sector_t block)
 {
+ unsigned long flags;
+ ata_request_t *ar;
+
         /*
          * Wait until all request have bin finished.
          */
@@ -338,16 +379,42 @@
                 return promise_rw_disk(drive, rq, block);
         }
 
+ /*
+ * get a new command (push ar further down to avoid grabbing lock here
+ */
+ spin_lock_irqsave(DRIVE_LOCK(drive), flags);
+
+ ar = ata_ar_get(drive);
+
+ /*
+ * we've reached maximum queue depth, bail
+ */
+ if (!ar) {
+ spin_unlock_irqrestore(DRIVE_LOCK(drive), flags);
+ return ide_started;
+ }
+
+ ar->ar_rq = rq;
+
+ if (drive->using_tcq) {
+ int tag = ide_get_tag(drive);
+
+ BUG_ON(drive->tcq->active_tag != -1);
+ IDE_SET_TAG(drive, ar, tag);
+ }
+
+ spin_unlock_irqrestore(DRIVE_LOCK(drive), flags);
+
         /* 48-bit LBA */
         if ((drive->id->cfs_enable_2 & 0x0400) && (drive->addressing))
- return lba48_do_request(drive, rq, block);
+ return lba48_do_request(drive, ar, block);
 
         /* 28-bit LBA */
         if (drive->select.b.lba)
- return lba28_do_request(drive, rq, block);
+ return lba28_do_request(drive, ar, block);
 
         /* 28-bit CHS */
- return chs_do_request(drive, rq, block);
+ return chs_do_request(drive, ar, block);
 }
 
 static int idedisk_open (struct inode *inode, struct file *filp, ide_drive_t *drive)
@@ -830,11 +897,71 @@
         PROC_IDE_READ_RETURN(page,start,off,count,eof,len);
 }
 
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+static int proc_idedisk_read_tcq
+ (char *page, char **start, off_t off, int count, int *eof, void *data)
+{
+ ide_drive_t *drive = (ide_drive_t *) data;
+ char *out = page;
+ int len, cmds, i;
+ unsigned long tag_mask = 0, flags, cur_jif = jiffies, max_jif;
+
+ if (!drive->tcq) {
+ len = sprintf(out, "not configured\n");
+ PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
+ }
+
+ spin_lock_irqsave(&ide_lock, flags);
+
+ len = sprintf(out, "TCQ currently on:\t%s\n", drive->using_tcq ? "yes" : "no");
+ len += sprintf(out+len, "Max queue depth:\t%d\n",drive->queue_depth);
+ len += sprintf(out+len, "Max achieved depth:\t%d\n",drive->tcq->max_depth);
+ len += sprintf(out+len, "Max depth since last:\t%d\n",drive->tcq->max_last_depth);
+ len += sprintf(out+len, "Current depth:\t\t%d\n", drive->tcq->queued);
+ max_jif = 0;
+ len += sprintf(out+len, "Active tags:\t\t[ ");
+ for (i = 0, cmds = 0; i < drive->queue_depth; i++) {
+ ata_request_t *ar = IDE_GET_AR(drive, i);
+
+ if (!ar)
+ continue;
+
+ __set_bit(i, &tag_mask);
+ len += sprintf(out+len, "%d, ", i);
+ if (ar->ar_time > max_jif)
+ max_jif = ar->ar_time;
+ cmds++;
+ }
+ len += sprintf(out+len, "]\n");
+
+ if (drive->tcq->queued != cmds)
+ len += sprintf(out+len, "pending request and queue count mismatch (%d)\n", cmds);
+
+ if (tag_mask != drive->tcq->tag_mask)
+ len += sprintf(out+len, "tag masks differ (counted %lx != %lx\n", tag_mask, drive->tcq->tag_mask);
+
+ len += sprintf(out+len, "DMA status:\t\t%srunning\n", test_bit(IDE_DMA, &HWGROUP(drive)->flags) ? "" : "not ");
+
+ if (max_jif)
+ len += sprintf(out+len, "Oldest command:\t\t%lu\n", cur_jif - max_jif);
+
+ len += sprintf(out+len, "immed rel %d, immed comp %d\n", drive->tcq->immed_rel, drive->tcq->immed_comp);
+
+ drive->tcq->max_last_depth = 0;
+
+ spin_unlock_irqrestore(&ide_lock, flags);
+ PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
+}
+#endif
+
 static ide_proc_entry_t idedisk_proc[] = {
         { "cache", S_IFREG|S_IRUGO, proc_idedisk_read_cache, NULL },
         { "geometry", S_IFREG|S_IRUGO, proc_ide_read_geometry, NULL },
         { "smart_values", S_IFREG|S_IRUSR, proc_idedisk_read_smart_values, NULL },
         { "smart_thresholds", S_IFREG|S_IRUSR, proc_idedisk_read_smart_thresholds, NULL },
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+ { "tcq", S_IFREG|S_IRUSR, proc_idedisk_read_tcq, NULL },
+#endif
         { NULL, 0, NULL, NULL }
 };
 
@@ -914,6 +1041,22 @@
         return 0;
 }
 
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+static int set_using_tcq(ide_drive_t *drive, int arg)
+{
+ if (!drive->driver)
+ return -EPERM;
+ if (!drive->channel->dmaproc)
+ return -EPERM;
+
+ drive->using_tcq = arg;
+ if (drive->channel->dmaproc(arg ? ide_dma_queued_on : ide_dma_queued_off, drive))
+ return -EIO;
+
+ return 0;
+}
+#endif
+
 static int probe_lba_addressing (ide_drive_t *drive, int arg)
 {
         drive->addressing = 0;
@@ -946,6 +1089,9 @@
         ide_add_setting(drive, "acoustic", SETTING_RW, HDIO_GET_ACOUSTIC, HDIO_SET_ACOUSTIC, TYPE_BYTE, 0, 254, 1, 1, &drive->acoustic, set_acoustic);
         ide_add_setting(drive, "failures", SETTING_RW, -1, -1, TYPE_INT, 0, 65535, 1, 1, &drive->failures, NULL);
         ide_add_setting(drive, "max_failures", SETTING_RW, -1, -1, TYPE_INT, 0, 65535, 1, 1, &drive->max_failures, NULL);
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+ ide_add_setting(drive, "using_tcq", SETTING_RW, HDIO_GET_QDMA, HDIO_SET_QDMA, TYPE_BYTE, 0, IDE_MAX_TAG, 1, 1, &drive->using_tcq, set_using_tcq);
+#endif
 }
 
 static int idedisk_suspend(struct device *dev, u32 state, u32 level)
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-dma.c linux/drivers/ide/ide-dma.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-dma.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide-dma.c Mon Apr 8 17:08:08 2002
@@ -82,6 +82,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/ide.h>
+#include <linux/delay.h>
 
 #include <asm/io.h>
 #include <asm/irq.h>
@@ -219,46 +220,49 @@
         return ide_error(drive, "dma_intr", stat);
 }
 
-static int ide_build_sglist(struct ata_channel *hwif, struct request *rq)
+int ide_build_sglist (struct ata_channel *hwif, struct request *rq)
 {
         request_queue_t *q = &hwif->drives[DEVICE_NR(rq->rq_dev) & 1].queue;
- struct scatterlist *sg = hwif->sg_table;
- int nents;
+ ata_request_t *ar = rq->special;
 
- nents = blk_rq_map_sg(q, rq, hwif->sg_table);
+ if (!(ar->ar_flags & ATA_AR_SETUP)) {
+ ar->ar_flags |= ATA_AR_SETUP;
+ ar->ar_sg_nents = blk_rq_map_sg(q, rq, ar->ar_sg_table);
+ }
 
- if (rq->q && nents > rq->nr_phys_segments)
- printk("ide-dma: received %d phys segments, build %d\n", rq->nr_phys_segments, nents);
+ if (rq->q && ar->ar_sg_nents > rq->nr_phys_segments) {
+ printk("ide-dma: received %d phys segments, build %d\n", rq->nr_phys_segments, ar->ar_sg_nents);
+ return 0;
+ } else if (!ar->ar_sg_nents) {
+ printk("ide-dma: zero segments in request\n");
+ return 0;
+ }
 
         if (rq_data_dir(rq) == READ)
- hwif->sg_dma_direction = PCI_DMA_FROMDEVICE;
+ ar->ar_sg_ddir = PCI_DMA_FROMDEVICE;
         else
- hwif->sg_dma_direction = PCI_DMA_TODEVICE;
+ ar->ar_sg_ddir = PCI_DMA_TODEVICE;
 
- return pci_map_sg(hwif->pci_dev, sg, nents, hwif->sg_dma_direction);
+ return pci_map_sg(hwif->pci_dev, ar->ar_sg_table, ar->ar_sg_nents, ar->ar_sg_ddir);
 }
 
+/*
+ * FIXME: taskfiles should be a map of pages, not a long virt address... /jens
+ */
 static int ide_raw_build_sglist(struct ata_channel *hwif, struct request *rq)
 {
- struct scatterlist *sg = hwif->sg_table;
- int nents = 0;
- ide_task_t *args = rq->special;
-#if 1
+ ata_request_t *ar = rq->special;
+ struct scatterlist *sg = ar->ar_sg_table;
+ ide_task_t *args = &ar->ar_task;
         unsigned char *virt_addr = rq->buffer;
         int sector_count = rq->nr_sectors;
-#else
- nents = blk_rq_map_sg(rq->q, rq, hwif->sg_table);
-
- if (nents > rq->nr_segments)
- printk("ide-dma: received %d segments, build %d\n", rq->nr_segments, nents);
-#endif
+ int nents = 0;
 
         if (args->command_type == IDE_DRIVE_TASK_RAW_WRITE)
- hwif->sg_dma_direction = PCI_DMA_TODEVICE;
+ ar->ar_sg_ddir = PCI_DMA_TODEVICE;
         else
- hwif->sg_dma_direction = PCI_DMA_FROMDEVICE;
+ ar->ar_sg_ddir = PCI_DMA_FROMDEVICE;
 
-#if 1
         if (sector_count > 128) {
                 memset(&sg[nents], 0, sizeof(*sg));
                 sg[nents].page = virt_to_page(virt_addr);
@@ -273,9 +277,8 @@
         sg[nents].offset = (unsigned long) virt_addr & ~PAGE_MASK;
         sg[nents].length = sector_count * SECTOR_SIZE;
         nents++;
- #endif
 
- return pci_map_sg(hwif->pci_dev, sg, nents, hwif->sg_dma_direction);
+ return pci_map_sg(hwif->pci_dev, sg, nents, ar->ar_sg_ddir);
 }
 
 /*
@@ -283,10 +286,10 @@
  * Returns 0 if all went okay, returns 1 otherwise.
  * May also be invoked from trm290.c
  */
-int ide_build_dmatable (ide_drive_t *drive, ide_dma_action_t func)
+int ide_build_dmatable(ide_drive_t *drive, struct request *rq,
+ ide_dma_action_t func)
 {
         struct ata_channel *hwif = drive->channel;
- unsigned int *table = hwif->dmatable_cpu;
 #ifdef CONFIG_BLK_DEV_TRM290
         unsigned int is_trm290_chipset = (hwif->chipset == ide_trm290);
 #else
@@ -295,16 +298,19 @@
         unsigned int count = 0;
         int i;
         struct scatterlist *sg;
+ ata_request_t *ar = rq->special;
+ unsigned int *table = ar->ar_dmatable_cpu;
 
- if (HWGROUP(drive)->rq->flags & REQ_DRIVE_TASKFILE) {
- hwif->sg_nents = i = ide_raw_build_sglist(hwif, HWGROUP(drive)->rq);
- } else {
- hwif->sg_nents = i = ide_build_sglist(hwif, HWGROUP(drive)->rq);
- }
- if (!i)
+ if (rq->flags & REQ_DRIVE_TASKFILE)
+ ar->ar_sg_nents = ide_raw_build_sglist(hwif, rq);
+ else
+ ar->ar_sg_nents = ide_build_sglist(hwif, rq);
+
+ if (!ar->ar_sg_nents)
                 return 0;
 
- sg = hwif->sg_table;
+ sg = ar->ar_sg_table;
+ i = ar->ar_sg_nents;
         while (i) {
                 u32 cur_addr;
                 u32 cur_len;
@@ -323,7 +329,7 @@
 
                         if (count++ >= PRD_ENTRIES) {
                                 printk("ide-dma: req %p\n", HWGROUP(drive)->rq);
- printk("count %d, sg_nents %d, cur_len %d, cur_addr %u\n", count, hwif->sg_nents, cur_len, cur_addr);
+ printk("count %d, sg_nents %d, cur_len %d, cur_addr %u\n", count, ar->ar_sg_nents, cur_len, cur_addr);
                                 BUG();
                         }
 
@@ -342,8 +348,8 @@
                          */
                                 if (count++ >= PRD_ENTRIES) {
                                         pci_unmap_sg(hwif->pci_dev, sg,
- hwif->sg_nents,
- hwif->sg_dma_direction);
+ ar->ar_sg_nents,
+ ar->ar_sg_ddir);
                                         return 0;
                                 }
 
@@ -372,10 +378,9 @@
 void ide_destroy_dmatable (ide_drive_t *drive)
 {
         struct pci_dev *dev = drive->channel->pci_dev;
- struct scatterlist *sg = drive->channel->sg_table;
- int nents = drive->channel->sg_nents;
+ ata_request_t *ar = IDE_CUR_AR(drive);
 
- pci_unmap_sg(dev, sg, nents, drive->channel->sg_dma_direction);
+ pci_unmap_sg(dev, ar->ar_sg_table, ar->ar_sg_nents, ar->ar_sg_ddir);
 }
 
 /*
@@ -536,6 +541,32 @@
 }
 
 /*
+ * start DMA engine
+ */
+int ide_start_dma(struct ata_channel *hwif, ide_drive_t *drive, ide_dma_action_t func)
+{
+ unsigned int reading = 0, count;
+ unsigned long dma_base = hwif->dma_base;
+ ata_request_t *ar = IDE_CUR_AR(drive);
+
+ if (rq_data_dir(ar->ar_rq) == READ)
+ reading = 1 << 3;
+
+ if (hwif->rwproc)
+ hwif->rwproc(drive, func);
+
+ if (!(count = ide_build_dmatable(drive, ar->ar_rq, func)))
+ return 1; /* try PIO instead of DMA */
+
+ ar->ar_flags |= ATA_AR_SETUP;
+ outl(ar->ar_dmatable, dma_base + 4); /* PRD table */
+ outb(reading, dma_base); /* specify r/w */
+ outb(inb(dma_base + 2) | 6, dma_base+2);/* clear INTR & ERROR flags */
+ drive->waiting_for_dma = 1;
+ return 0;
+}
+
+/*
  * ide_dmaproc() initiates/aborts DMA read/write operations on a drive.
  *
  * The caller is assumed to have selected the drive and programmed the drive's
@@ -556,14 +587,16 @@
         struct ata_channel *hwif = drive->channel;
         unsigned long dma_base = hwif->dma_base;
         byte unit = (drive->select.b.unit & 0x01);
- unsigned int count, reading = 0, set_high = 1;
+ unsigned int reading = 0, set_high = 1;
+ ata_request_t *ar;
         byte dma_stat;
 
         switch (func) {
                 case ide_dma_off:
                         printk("%s: DMA disabled\n", drive->name);
- set_high = 0;
                 case ide_dma_off_quietly:
+ set_high = 0;
+ drive->using_tcq = 0;
                         outb(inb(dma_base+2) & ~(1<<(5+unit)), dma_base+2);
                 case ide_dma_on:
                         ide_toggle_bounce(drive, set_high);
@@ -573,48 +606,65 @@
                         return 0;
                 case ide_dma_check:
                         return config_drive_for_dma (drive);
+ case ide_dma_begin:
+#ifdef DEBUG
+ printk("ide_dma_begin: from %p\n", __builtin_return_address(0));
+#endif
+ if (test_and_set_bit(IDE_DMA, &HWGROUP(drive)->flags))
+ BUG();
+ /* Note that this is done *after* the cmd has
+ * been issued to the drive, as per the BM-IDE spec.
+ * The Promise Ultra33 doesn't work correctly when
+ * we do this part before issuing the drive cmd.
+ */
+ outb(inb(dma_base)|1, dma_base); /* start DMA */
+ return 0;
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+ case ide_dma_queued_on:
+ case ide_dma_queued_off:
+ case ide_dma_read_queued:
+ case ide_dma_write_queued:
+ case ide_dma_queued_start:
+ return ide_tcq_dmaproc(func, drive);
+#endif /* CONFIG_BLK_DEV_IDE_TCQ */
+
                 case ide_dma_read:
                         reading = 1 << 3;
                 case ide_dma_write:
- /* active tuning based on IO direction */
- if (hwif->rwproc)
- hwif->rwproc(drive, func);
-
- if (!(count = ide_build_dmatable(drive, func)))
- return 1; /* try PIO instead of DMA */
- outl(hwif->dmatable_dma, dma_base + 4); /* PRD table */
- outb(reading, dma_base); /* specify r/w */
- outb(inb(dma_base+2)|6, dma_base+2); /* clear INTR & ERROR flags */
- drive->waiting_for_dma = 1;
+ ar = HWGROUP(drive)->rq->special;
+
+ if (ide_start_dma(hwif, drive, func))
+ return 1;
+
                         if (drive->type != ATA_DISK)
                                 return 0;
-
                         BUG_ON(HWGROUP(drive)->handler);
                         ide_set_handler(drive, &ide_dma_intr, WAIT_CMD, dma_timer_expiry); /* issue cmd to drive */
- if ((HWGROUP(drive)->rq->flags & REQ_DRIVE_TASKFILE) &&
+ if ((ar->ar_rq->flags & REQ_DRIVE_TASKFILE) &&
                             (drive->addressing == 1)) {
- ide_task_t *args = HWGROUP(drive)->rq->special;
+ ide_task_t *args = &ar->ar_task;
                                 OUT_BYTE(args->taskfile.command, IDE_COMMAND_REG);
                         } else if (drive->addressing) {
                                 OUT_BYTE(reading ? WIN_READDMA_EXT : WIN_WRITEDMA_EXT, IDE_COMMAND_REG);
                         } else {
                                 OUT_BYTE(reading ? WIN_READDMA : WIN_WRITEDMA, IDE_COMMAND_REG);
                         }
- return drive->channel->dmaproc(ide_dma_begin, drive);
- case ide_dma_begin:
- /* Note that this is done *after* the cmd has
- * been issued to the drive, as per the BM-IDE spec.
- * The Promise Ultra33 doesn't work correctly when
- * we do this part before issuing the drive cmd.
- */
- outb(inb(dma_base)|1, dma_base); /* start DMA */
- return 0;
+ return hwif->dmaproc(ide_dma_begin, drive);
                 case ide_dma_end: /* returns 1 on error, 0 otherwise */
+#ifdef DEBUG
+ printk("ide_dma_end: from %p\n", __builtin_return_address(0));
+#endif
+ if (!test_and_clear_bit(IDE_DMA, &HWGROUP(drive)->flags)) {
+ printk("ide_dma_end: dma not going? %p\n", __builtin_return_address(0));
+ return 1;
+ }
                         drive->waiting_for_dma = 0;
                         outb(inb(dma_base)&~1, dma_base); /* stop DMA */
- dma_stat = inb(dma_base+2); /* get DMA status */
+ dma_stat = inb(dma_base+2); /* get DMA status */
                         outb(dma_stat|6, dma_base+2); /* clear the INTR & ERROR bits */
                         ide_destroy_dmatable(drive); /* purge DMA mappings */
+ if (drive->tcq)
+ IDE_SET_CUR_TAG(drive, -1);
                         return (dma_stat & 7) != 4 ? (0x10 | dma_stat) : 0; /* verify good DMA status */
                 case ide_dma_test_irq: /* returns 1 if dma irq issued, 0 otherwise */
                         dma_stat = inb(dma_base+2);
@@ -651,17 +701,6 @@
         if (!hwif->dma_base)
                 return;
 
- if (hwif->dmatable_cpu) {
- pci_free_consistent(hwif->pci_dev,
- PRD_ENTRIES * PRD_BYTES,
- hwif->dmatable_cpu,
- hwif->dmatable_dma);
- hwif->dmatable_cpu = NULL;
- }
- if (hwif->sg_table) {
- kfree(hwif->sg_table);
- hwif->sg_table = NULL;
- }
         if ((hwif->dma_extra) && (hwif->unit == 0))
                 release_region((hwif->dma_base + 16), hwif->dma_extra);
         release_region(hwif->dma_base, 8);
@@ -680,19 +719,6 @@
         }
         request_region(dma_base, num_ports, hwif->name);
         hwif->dma_base = dma_base;
- hwif->dmatable_cpu = pci_alloc_consistent(hwif->pci_dev,
- PRD_ENTRIES * PRD_BYTES,
- &hwif->dmatable_dma);
- if (hwif->dmatable_cpu == NULL)
- goto dma_alloc_failure;
-
- hwif->sg_table = kmalloc(sizeof(struct scatterlist) * PRD_ENTRIES,
- GFP_KERNEL);
- if (hwif->sg_table == NULL) {
- pci_free_consistent(hwif->pci_dev, PRD_ENTRIES * PRD_BYTES,
- hwif->dmatable_cpu, hwif->dmatable_dma);
- goto dma_alloc_failure;
- }
 
         hwif->dmaproc = &ide_dmaproc;
 
@@ -704,7 +730,4 @@
         }
         printk("\n");
         return;
-
-dma_alloc_failure:
- printk(" -- ERROR, UNABLE TO ALLOCATE DMA TABLES\n");
 }
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-features.c linux/drivers/ide/ide-features.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-features.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide-features.c Thu Apr 4 08:14:18 2002
@@ -75,10 +75,7 @@
 char *ide_dmafunc_verbose (ide_dma_action_t dmafunc)
 {
         switch (dmafunc) {
- case ide_dma_read: return("ide_dma_read");
- case ide_dma_write: return("ide_dma_write");
                 case ide_dma_begin: return("ide_dma_begin");
- case ide_dma_end: return("ide_dma_end:");
                 case ide_dma_check: return("ide_dma_check");
                 case ide_dma_on: return("ide_dma_on");
                 case ide_dma_off: return("ide_dma_off");
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-probe.c linux/drivers/ide/ide-probe.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-probe.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide-probe.c Tue Apr 9 13:58:09 2002
@@ -189,6 +189,21 @@
         if (drive->channel->quirkproc)
                 drive->quirk_list = drive->channel->quirkproc(drive);
 
+ /*
+ * it's an ata drive, build command list
+ */
+#ifndef CONFIG_BLK_DEV_IDE_TCQ
+ drive->queue_depth = 1;
+#else
+ drive->queue_depth = drive->id->queue_depth + 1;
+ if (drive->queue_depth > CONFIG_BLK_DEV_IDE_TCQ_DEPTH)
+ drive->queue_depth = CONFIG_BLK_DEV_IDE_TCQ_DEPTH;
+ if (drive->queue_depth < 1 || drive->queue_depth > IDE_MAX_TAG)
+ drive->queue_depth = IDE_MAX_TAG;
+#endif
+ if (ide_build_commandlist(drive))
+ goto err_misc;
+
         return;
 
 err_misc:
@@ -593,10 +608,10 @@
         blk_queue_max_sectors(q, max_sectors);
 
         /* IDE DMA can do PRD_ENTRIES number of segments. */
- blk_queue_max_hw_segments(q, PRD_ENTRIES);
+ blk_queue_max_hw_segments(q, PRD_SEGMENTS);
 
         /* This is a driver limit and could be eliminated. */
- blk_queue_max_phys_segments(q, PRD_ENTRIES);
+ blk_queue_max_phys_segments(q, PRD_SEGMENTS);
 }
 
 #if MAX_HWIFS > 1
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-taskfile.c linux/drivers/ide/ide-taskfile.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-taskfile.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide-taskfile.c Mon Apr 8 10:19:33 2002
@@ -291,7 +291,8 @@
 
 static ide_startstop_t pre_task_mulout_intr(ide_drive_t *drive, struct request *rq)
 {
- ide_task_t *args = rq->special;
+ ata_request_t *ar = rq->special;
+ ide_task_t *args = &ar->ar_task;
         ide_startstop_t startstop;
 
         /*
@@ -438,8 +439,32 @@
                 if (prehandler != NULL)
                         return prehandler(drive, rq);
         } else {
- /* for dma commands we down set the handler */
- if (drive->using_dma && !(drive->channel->dmaproc(((taskfile->command == WIN_WRITEDMA) || (taskfile->command == WIN_WRITEDMA_EXT)) ? ide_dma_write : ide_dma_read, drive)));
+ ide_dma_action_t dmaaction;
+
+ if (!drive->using_dma)
+ return ide_started;
+
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+ if (drive->using_tcq) {
+ if (taskfile->command == WIN_READDMA_QUEUED
+ || taskfile->command == WIN_READDMA_QUEUED_EXT
+ || taskfile->command == WIN_WRITEDMA_QUEUED
+ || taskfile->command == WIN_READDMA_QUEUED_EXT)
+ return ide_start_tag(ide_dma_queued_start, drive, rq->special);
+ }
+#endif /* CONFIG_BLK_DEV_IDE_TCQ */
+
+ if (taskfile->command == WIN_WRITEDMA || taskfile->command == WIN_WRITEDMA_EXT)
+ dmaaction = ide_dma_write;
+ else if (taskfile->command == WIN_READDMA || taskfile->command == WIN_READDMA_EXT)
+ dmaaction = ide_dma_read;
+ else
+ return ide_stopped;
+
+ if (!drive->channel->dmaproc(dmaaction, drive))
+ return ide_started;
+
+ return ide_stopped;
         }
 
         return ide_started;
@@ -496,7 +521,8 @@
  */
 ide_startstop_t task_no_data_intr (ide_drive_t *drive)
 {
- ide_task_t *args = HWGROUP(drive)->rq->special;
+ ata_request_t *ar = HWGROUP(drive)->rq->special;
+ ide_task_t *args = &ar->ar_task;
         byte stat = GET_STAT();
 
         ide__sti(); /* local CPU only */
@@ -556,7 +582,8 @@
 
 static ide_startstop_t pre_task_out_intr (ide_drive_t *drive, struct request *rq)
 {
- ide_task_t *args = rq->special;
+ ata_request_t *ar = rq->special;
+ ide_task_t *args = &ar->ar_task;
         ide_startstop_t startstop;
 
         if (ide_wait_stat(&startstop, drive, DATA_READY, drive->bad_wstat, WAIT_DRQ)) {
@@ -645,7 +672,7 @@
 
                 pBuf = ide_map_rq(rq, &flags);
 
- DTF("Multiread: %p, nsect: %d , rq->current_nr_sectors: %ld\n",
+ DTF("Multiread: %p, nsect: %d , rq->current_nr_sectors: %d\n",
                         pBuf, nsect, rq->current_nr_sectors);
                 drive->io_32bit = 0;
                 taskfile_input_data(drive, pBuf, nsect * SECTOR_WORDS);
@@ -859,7 +886,7 @@
 /*
  * This function is intended to be used prior to invoking ide_do_drive_cmd().
  */
-static void init_taskfile_request(struct request *rq)
+void init_taskfile_request(struct request *rq)
 {
         memset(rq, 0, sizeof(*rq));
         rq->flags = REQ_DRIVE_TASKFILE;
@@ -877,22 +904,24 @@
 {
         struct request rq;
         /* FIXME: This is on stack! */
- ide_task_t args;
+ ata_request_t ar;
+ ide_task_t *args = &ar.ar_task;
 
- memset(&args, 0, sizeof(ide_task_t));
+ ATA_AR_INIT(drive, &ar);
 
- args.taskfile = *taskfile;
- args.hobfile = *hobfile;
+ memcpy(&args->taskfile, taskfile, sizeof(*taskfile));
+ if (hobfile)
+ memcpy(&args->hobfile, hobfile, sizeof(*hobfile));
 
         init_taskfile_request(&rq);
 
         /* This is kept for internal use only !!! */
- ide_cmd_type_parser(&args);
- if (args.command_type != IDE_DRIVE_TASK_NO_DATA)
+ ide_cmd_type_parser(args);
+ if (args->command_type != IDE_DRIVE_TASK_NO_DATA)
                 rq.current_nr_sectors = rq.nr_sectors = (hobfile->sector_count << 8) | taskfile->sector_count;
 
         rq.buffer = buf;
- rq.special = &args;
+ rq.special = &ar;
 
         return ide_do_drive_cmd(drive, &rq, ide_wait);
 }
@@ -900,15 +929,19 @@
 int ide_raw_taskfile(ide_drive_t *drive, ide_task_t *args, byte *buf)
 {
         struct request rq;
+ ata_request_t ar;
+
+ ATA_AR_INIT(drive, &ar);
         init_taskfile_request(&rq);
         rq.buffer = buf;
+ memcpy(&ar.ar_task, args, sizeof(*args));
 
         if (args->command_type != IDE_DRIVE_TASK_NO_DATA)
                 rq.current_nr_sectors = rq.nr_sectors
                         = (args->hobfile.sector_count << 8)
                         | args->taskfile.sector_count;
 
- rq.special = args;
+ rq.special = &ar;
 
         return ide_do_drive_cmd(drive, &rq, ide_wait);
 }
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-tcq.c linux/drivers/ide/ide-tcq.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide-tcq.c Thu Jan 1 01:00:00 1970
+++ linux/drivers/ide/ide-tcq.c Tue Apr 9 14:17:42 2002
@@ -0,0 +1,590 @@
+/*
+ * Copyright (C) 2001, 2002 Jens Axboe <axboe@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * Support for the DMA queued protocol, which enables ATA disk drives to
+ * use tagged command queueing
+ */
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ide.h>
+
+#include <asm/delay.h>
+
+/*
+ * warning: it will be _very_ verbose if set to 1
+ */
+#if 0
+#define TCQ_PRINTK printk
+#else
+#define TCQ_PRINTK(x...)
+#endif
+
+/*
+ * use nIEN or not
+ */
+#undef IDE_TCQ_NIEN
+
+/*
+ * we are leaving the SERVICE interrupt alone, IBM drives have it
+ * on per default and it can't be turned off. Doesn't matter, this
+ * is the sane config.
+ */
+#undef IDE_TCQ_FIDDLE_SI
+
+int ide_tcq_end(ide_drive_t *drive);
+ide_startstop_t ide_dmaq_intr(ide_drive_t *drive);
+
+static inline void drive_ctl_nien(ide_drive_t *drive, int clear)
+{
+#ifdef IDE_TCQ_NIEN
+ int mask = clear ? 0 : 2;
+
+ if (IDE_CONTROL_REG)
+ OUT_BYTE(drive->ctl | mask, IDE_CONTROL_REG);
+#endif
+}
+
+/*
+ * if we encounter _any_ error doing I/O to one of the tags, we must
+ * invalidate the pending queue. clear the software busy queue and requeue
+ * on the request queue for restart. issue a WIN_NOP to clear hardware queue
+ */
+static void ide_tcq_invalidate_queue(ide_drive_t *drive)
+{
+ request_queue_t *q = &drive->queue;
+ unsigned long flags;
+ ata_request_t *ar;
+ int i;
+
+ printk("%s: invalidating pending queue\n", drive->name);
+
+ spin_lock_irqsave(&ide_lock, flags);
+
+ del_timer(&HWGROUP(drive)->timer);
+
+ /*
+ * assume oldest commands have the higher tags... doesn't matter
+ * much. shove requests back into request queue.
+ */
+ for (i = drive->queue_depth - 1; i; i--) {
+ ar = drive->tcq->ar[i];
+ if (!ar)
+ continue;
+
+ ar->ar_rq->special = NULL;
+ ar->ar_rq->flags &= ~REQ_STARTED;
+ _elv_add_request(q, ar->ar_rq, 0, 0);
+ ata_ar_put(drive, ar);
+ }
+
+ drive->tcq->queued = 0;
+ drive->using_tcq = 0;
+ drive->queue_depth = 1;
+ clear_bit(IDE_BUSY, &HWGROUP(drive)->flags);
+ clear_bit(IDE_DMA, &HWGROUP(drive)->flags);
+ HWGROUP(drive)->handler = NULL;
+
+ /*
+ * do some internal stuff -- we really need this command to be
+ * executed before any new commands are started. issue a NOP
+ * to clear internal queue on drive
+ */
+ ar = ata_ar_get(drive);
+
+ memset(&ar->ar_task, 0, sizeof(ar->ar_task));
+ AR_TASK_CMD(ar) = WIN_NOP;
+ ide_cmd_type_parser(&ar->ar_task);
+ ar->ar_rq = &HWGROUP(drive)->wrq;
+ init_taskfile_request(ar->ar_rq);
+ ar->ar_rq->rq_dev = mk_kdev(drive->channel->major, (drive->select.b.unit)<<PARTN_BITS);
+ ar->ar_rq->special = ar;
+ ar->ar_flags |= ATA_AR_RETURN;
+ _elv_add_request(q, ar->ar_rq, 0, 0);
+
+ /*
+ * make sure that nIEN is cleared
+ */
+ drive_ctl_nien(drive, 0);
+
+ /*
+ * start doing stuff again
+ */
+ q->request_fn(q);
+ spin_unlock_irqrestore(&ide_lock, flags);
+ printk("ide_tcq_invalidate_queue: done\n");
+}
+
+void ide_tcq_intr_timeout(unsigned long data)
+{
+ ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
+ unsigned long flags;
+ ide_drive_t *drive;
+
+ printk("ide_tcq_intr_timeout: timeout waiting for interrupt...\n");
+
+ spin_lock_irqsave(&ide_lock, flags);
+
+ if (test_bit(IDE_BUSY, &hwgroup->flags))
+ printk("ide_tcq_intr_timeout: hwgroup not busy\n");
+ if (hwgroup->handler == NULL)
+ printk("ide_tcq_intr_timeout: missing isr!\n");
+ if ((drive = hwgroup->drive) == NULL)
+ printk("ide_tcq_intr_timeout: missing drive!\n");
+
+ spin_unlock_irqrestore(&ide_lock, flags);
+
+ if (drive)
+ ide_tcq_invalidate_queue(drive);
+}
+
+void ide_tcq_set_intr(ide_hwgroup_t *hwgroup, ide_handler_t *handler)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ide_lock, flags);
+
+ /*
+ * always just bump the timer for now, the timeout handling will
+ * have to be changed to be per-command
+ */
+ hwgroup->timer.function = ide_tcq_intr_timeout;
+ hwgroup->timer.data = (unsigned long) hwgroup;
+ mod_timer(&hwgroup->timer, jiffies + 5 * HZ);
+
+ hwgroup->handler = handler;
+ spin_unlock_irqrestore(&ide_lock, flags);
+}
+
+/*
+ * wait 400ns, then poll for busy_mask to clear from alt status
+ */
+#define IDE_TCQ_WAIT (10000)
+int ide_tcq_wait_altstat(ide_drive_t *drive, byte *stat, byte busy_mask)
+{
+ int i;
+
+ /*
+ * one initial udelay(1) should be enough, reading alt stat should
+ * provide the required delay...
+ */
+ *stat = 0;
+ i = 0;
+ do {
+ udelay(1);
+
+ if (unlikely(i++ > IDE_TCQ_WAIT))
+ return 1;
+ } while ((*stat = GET_ALTSTAT()) & busy_mask);
+
+ return 0;
+}
+
+/*
+ * issue SERVICE command to drive -- drive must have been selected first,
+ * and it must have reported a need for service (status has SERVICE_STAT set)
+ *
+ * Also, nIEN must be set as not to need protection against ide_dmaq_intr
+ */
+ide_startstop_t ide_service(ide_drive_t *drive)
+{
+ ata_request_t *ar;
+ byte feat, tag, stat;
+
+ if (test_bit(IDE_DMA, &HWGROUP(drive)->flags))
+ printk("ide_service: DMA in progress\n");
+
+ /*
+ * need to select the right drive first...
+ */
+ if (drive != HWGROUP(drive)->drive) {
+ SELECT_DRIVE(drive->channel, drive);
+ udelay(10);
+ }
+
+ drive_ctl_nien(drive, 1);
+
+ /*
+ * send SERVICE, wait 400ns, wait for BUSY_STAT to clear
+ */
+ OUT_BYTE(WIN_QUEUED_SERVICE, IDE_COMMAND_REG);
+
+ if (ide_tcq_wait_altstat(drive, &stat, BUSY_STAT)) {
+ printk("ide_service: BUSY clear took too long\n");
+ ide_tcq_invalidate_queue(drive);
+ return ide_stopped;
+ }
+
+ drive_ctl_nien(drive, 0);
+
+ /*
+ * FIXME, invalidate queue
+ */
+ if (stat & ERR_STAT) {
+ printk("%s: error SERVICING drive (%x)\n", drive->name, stat);
+ ide_dump_status(drive, "ide_service", stat);
+ return ide_tcq_end(drive);
+ }
+
+ /*
+ * should not happen, a buggy device could introduce loop
+ */
+ if ((feat = GET_FEAT()) & NSEC_REL) {
+ printk("%s: release in service\n", drive->name);
+ IDE_SET_CUR_TAG(drive, -1);
+ return ide_stopped;
+ }
+
+ /*
+ * start dma
+ */
+ tag = feat >> 3;
+ IDE_SET_CUR_TAG(drive, tag);
+
+ TCQ_PRINTK("ide_service: stat %x, feat %x\n", stat, feat);
+
+ if ((ar = IDE_CUR_TAG(drive)) == NULL) {
+ printk("ide_service: missing request for tag %d\n", tag);
+ return ide_stopped;
+ }
+
+ /*
+ * we'll start a dma read or write, device will trigger
+ * interrupt to indicate end of transfer, release is not allowed
+ */
+ if (rq_data_dir(ar->ar_rq) == READ) {
+ TCQ_PRINTK("ide_service: starting READ %x\n", stat);
+ drive->channel->dmaproc(ide_dma_read_queued, drive);
+ } else {
+ TCQ_PRINTK("ide_service: starting WRITE %x\n", stat);
+ drive->channel->dmaproc(ide_dma_write_queued, drive);
+ }
+
+ /*
+ * dmaproc set intr handler
+ */
+ return ide_started;
+}
+
+ide_startstop_t ide_check_service(ide_drive_t *drive)
+{
+ byte stat;
+
+ if (!ide_pending_commands(drive))
+ return ide_stopped;
+
+ if ((stat = GET_STAT()) & SERVICE_STAT)
+ return ide_service(drive);
+
+ /*
+ * we have pending commands, wait for interrupt
+ */
+ ide_tcq_set_intr(HWGROUP(drive), ide_dmaq_intr);
+ return ide_started;
+}
+
+int ide_tcq_end(ide_drive_t *drive)
+{
+ byte stat = GET_STAT();
+
+ if (stat & ERR_STAT) {
+ ide_dump_status(drive, "ide_tcq_end", stat);
+ ide_tcq_invalidate_queue(drive);
+ return ide_stopped;
+ } else if (stat & SERVICE_STAT) {
+ TCQ_PRINTK("ide_tcq_end: serv stat=%x\n", stat);
+ return ide_service(drive);
+ }
+
+ TCQ_PRINTK("ide_tcq_end: stat=%x, feat=%x\n", stat, GET_FEAT());
+ return ide_stopped;
+}
+
+ide_startstop_t ide_dmaq_complete(ide_drive_t *drive, byte stat)
+{
+ ata_request_t *ar;
+ byte dma_stat;
+
+#if 0
+ byte feat = GET_FEAT();
+
+ if ((feat & (NSEC_CD | NSEC_IO)) != (NSEC_CD | NSEC_IO))
+ printk("%s: C/D | I/O not set\n", drive->name);
+#endif
+
+ /*
+ * transfer was in progress, stop DMA engine
+ */
+ ar = IDE_CUR_TAG(drive);
+
+ dma_stat = drive->channel->dmaproc(ide_dma_end, drive);
+
+ /*
+ * must be end of I/O, check status and complete as necessary
+ */
+ if (unlikely(!OK_STAT(stat, READY_STAT, drive->bad_wstat | DRQ_STAT))) {
+ printk("ide_dmaq_intr: %s: error status %x\n", drive->name, stat);
+ ide_dump_status(drive, "ide_dmaq_intr", stat);
+ ide_tcq_invalidate_queue(drive);
+ return ide_stopped;
+ }
+
+ if (dma_stat)
+ printk("%s: bad DMA status (dma_stat=%x)\n", drive->name, dma_stat);
+
+ TCQ_PRINTK("ide_dmaq_intr: ending %p, tag %d\n", ar, ar->ar_tag);
+ ide_end_queued_request(drive, !dma_stat, ar->ar_rq);
+
+ IDE_SET_CUR_TAG(drive, -1);
+ return ide_check_service(drive);
+}
+
+/*
+ * intr handler for queued dma operations. this can be entered for two
+ * reasons:
+ *
+ * 1) device has completed dma transfer
+ * 2) service request to start a command
+ *
+ * if the drive has an active tag, we first complete that request before
+ * processing any pending SERVICE.
+ */
+ide_startstop_t ide_dmaq_intr(ide_drive_t *drive)
+{
+ byte stat = GET_STAT();
+
+ TCQ_PRINTK("ide_dmaq_intr: stat=%x, tag %d\n", stat, drive->tcq->active_tag);
+
+ /*
+ * if a command completion interrupt is pending, do that first and
+ * check service afterwards
+ */
+ if (drive->tcq->active_tag != -1)
+ return ide_dmaq_complete(drive, stat);
+
+ /*
+ * service interrupt
+ */
+ if (stat & SERVICE_STAT) {
+ TCQ_PRINTK("ide_dmaq_intr: SERV (stat=%x)\n", stat);
+ return ide_service(drive);
+ }
+
+ printk("ide_dmaq_intr: stat=%x, not expected\n", stat);
+ return ide_check_service(drive);
+}
+
+/*
+ * configure the drive for tcq
+ */
+static int ide_tcq_configure(ide_drive_t *drive)
+{
+ struct hd_drive_task_hdr taskfile;
+ int tcq_supp = 1 << 1 | 1 << 14;
+
+ memset(&taskfile, 0, sizeof(taskfile));
+
+ /*
+ * bit 14 and 1 must be set in word 83 of the device id to indicate
+ * support for dma queued protocol
+ */
+ if ((drive->id->command_set_2 & tcq_supp) != tcq_supp) {
+ printk("%s: queued feature set not supported\n", drive->name);
+ return 1;
+ }
+
+ taskfile.feature = SETFEATURES_EN_WCACHE;
+ taskfile.command = WIN_SETFEATURES;
+ if (ide_wait_taskfile(drive, &taskfile, NULL, NULL)) {
+ printk("%s: failed to enable write cache\n", drive->name);
+ return 1;
+ }
+
+ /*
+ * disable RELease interrupt, it's quicker to poll this after
+ * having sent the command opcode
+ */
+ taskfile.feature = SETFEATURES_DIS_RI;
+ taskfile.command = WIN_SETFEATURES;
+ if (ide_wait_taskfile(drive, &taskfile, NULL, NULL)) {
+ printk("%s: disabling release interrupt fail\n", drive->name);
+ return 1;
+ }
+
+#ifdef IDE_TCQ_FIDDLE_SI
+ /*
+ * enable SERVICE interrupt
+ */
+ taskfile.feature = SETFEATURES_EN_SI;
+ taskfile.command = WIN_SETFEATURES;
+ if (ide_wait_taskfile(drive, &taskfile, NULL, NULL)) {
+ printk("%s: enabling service interrupt fail\n", drive->name);
+ return 1;
+ }
+#endif
+ return 0;
+}
+
+/*
+ * for now assume that command list is always as big as we need and don't
+ * attempt to shrink it on tcq disable
+ */
+static int ide_enable_queued(ide_drive_t *drive, int on)
+{
+ /*
+ * disable or adjust queue depth
+ */
+ if (!on) {
+ printk("%s: TCQ disabled\n", drive->name);
+ drive->using_tcq = 0;
+ return 0;
+ } else if (on && drive->using_tcq) {
+ drive->queue_depth = drive->using_tcq;
+ goto out;
+ }
+
+ if (ide_tcq_configure(drive)) {
+ drive->using_tcq = 0;
+ return 1;
+ }
+
+out:
+ drive->tcq->max_depth = 0;
+
+ printk("%s: tagged command queueing enabled, command queue depth %d\n", drive->name, drive->queue_depth);
+ drive->using_tcq = 1;
+ return 0;
+}
+
+int ide_tcq_dmaproc(ide_dma_action_t func, ide_drive_t *drive)
+{
+ struct ata_channel *hwif = drive->channel;
+ unsigned int reading = 0, enable_tcq = 1;
+ ide_startstop_t startstop;
+ ata_request_t *ar;
+ byte stat, feat;
+
+ switch (func) {
+ /*
+ * invoked from a SERVICE interrupt, command etc already known.
+ * just need to start the dma engine for this tag
+ */
+ case ide_dma_read_queued:
+ reading = 1 << 3;
+ case ide_dma_write_queued:
+ TCQ_PRINTK("ide_dma: setting up queued %d\n", drive->tcq->active_tag);
+ BUG_ON(drive->tcq->active_tag == -1);
+
+ if (!test_bit(IDE_BUSY, &HWGROUP(drive)->flags))
+ printk("queued_rw: IDE_BUSY not set\n");
+
+ if (ide_wait_stat(&startstop, drive, READY_STAT | DRQ_STAT, BUSY_STAT, WAIT_READY)) {
+ printk("%s: timeout waiting for data phase\n", drive->name);
+ return startstop;
+ }
+
+ if (ide_start_dma(hwif, drive, func))
+ return 1;
+
+ ide_tcq_set_intr(HWGROUP(drive), ide_dmaq_intr);
+ return hwif->dmaproc(ide_dma_begin, drive);
+
+ /*
+ * start a queued command from scratch
+ */
+ case ide_dma_queued_start:
+ BUG_ON(drive->tcq->active_tag == -1);
+ ar = IDE_CUR_TAG(drive);
+
+ /*
+ * set nIEN, tag start operation will enable again when
+ * it is safe
+ */
+ drive_ctl_nien(drive, 1);
+
+ OUT_BYTE(AR_TASK_CMD(ar), IDE_COMMAND_REG);
+
+ if (ide_tcq_wait_altstat(drive, &stat, BUSY_STAT)) {
+ printk("ide_dma_queued_start: abort (stat=%x)\n", stat);
+ return ide_stopped;
+ }
+
+ drive_ctl_nien(drive, 0);
+
+ if (stat & ERR_STAT) {
+ printk("ide_dma_queued_start: abort (stat=%x)\n", stat);
+ return ide_stopped;
+ }
+
+ if ((feat = GET_FEAT()) & NSEC_REL) {
+ drive->tcq->immed_rel++;
+ TCQ_PRINTK("REL in queued_start\n");
+ IDE_SET_CUR_TAG(drive, -1);
+
+ if ((stat = GET_STAT()) & SERVICE_STAT)
+ return ide_service(drive);
+
+ ide_tcq_set_intr(HWGROUP(drive), ide_dmaq_intr);
+ return ide_released;
+ }
+
+ drive->tcq->immed_comp++;
+
+ if (ide_wait_stat(&startstop, drive, READY_STAT | DRQ_STAT, BUSY_STAT, WAIT_READY)) {
+ printk("%s: timeout waiting for data phase\n", drive->name);
+ return startstop;
+ }
+
+ if (ide_start_dma(hwif, drive, func))
+ return ide_stopped;
+
+ if (hwif->dmaproc(ide_dma_begin, drive))
+ return ide_stopped;
+
+ /*
+ * wait for SERVICE or completion interrupt
+ */
+ ide_tcq_set_intr(HWGROUP(drive), ide_dmaq_intr);
+ return ide_started;
+
+ case ide_dma_queued_off:
+ enable_tcq = 0;
+ case ide_dma_queued_on:
+ return ide_enable_queued(drive, enable_tcq);
+ default:
+ break;
+ }
+
+ return 1;
+}
+
+int ide_build_sglist (struct ata_channel *hwif, struct request *rq);
+ide_startstop_t ide_start_tag(ide_dma_action_t func, ide_drive_t *drive,
+ ata_request_t *ar)
+{
+ /*
+ * do this now, no need to run that with interrupts disabled
+ */
+ if (!ide_build_sglist(drive->channel, ar->ar_rq))
+ return ide_stopped;
+
+ IDE_SET_CUR_TAG(drive, ar->ar_tag);
+ return ide_tcq_dmaproc(func, drive);
+}
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide.c linux/drivers/ide/ide.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/ide.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/ide.c Tue Apr 9 14:05:35 2002
@@ -368,6 +368,25 @@
         return 0; /* no, it is not a flash memory card */
 }
 
+void ide_end_queued_request(ide_drive_t *drive, int uptodate, struct request *rq)
+{
+ unsigned long flags;
+
+ BUG_ON(!(rq->flags & REQ_STARTED));
+ BUG_ON(!rq->special);
+
+ if (!end_that_request_first(rq, uptodate, rq->hard_nr_sectors)) {
+ ata_request_t *ar = rq->special;
+
+ add_blkdev_randomness(major(rq->rq_dev));
+
+ spin_lock_irqsave(&ide_lock, flags);
+ ata_ar_put(drive, ar);
+ end_that_request_last(rq);
+ spin_unlock_irqrestore(&ide_lock, flags);
+ }
+}
+
 int __ide_end_request(ide_drive_t *drive, int uptodate, int nr_secs)
 {
         struct request *rq;
@@ -396,9 +415,17 @@
         }
 
         if (!end_that_request_first(rq, uptodate, nr_secs)) {
+ ata_request_t *ar = rq->special;
+
                 add_blkdev_randomness(major(rq->rq_dev));
+ /*
+ * request with ATA_AR_QUEUED set have already been
+ * dequeued, but doing it twice is ok
+ */
                 blkdev_dequeue_request(rq);
                 HWGROUP(drive)->rq = NULL;
+ if (ar)
+ ata_ar_put(drive, ar);
                 end_that_request_last(rq);
                 ret = 0;
         }
@@ -422,8 +449,8 @@
 
         spin_lock_irqsave(&ide_lock, flags);
         if (hwgroup->handler != NULL) {
- printk("%s: ide_set_handler: handler not null; old=%p, new=%p\n",
- drive->name, hwgroup->handler, handler);
+ printk("%s: ide_set_handler: handler not null; old=%p, new=%p, from %p\n",
+ drive->name, hwgroup->handler, handler, __builtin_return_address(0));
         }
         hwgroup->handler = handler;
         hwgroup->expiry = expiry;
@@ -738,8 +765,11 @@
                         args[6] = IN_BYTE(IDE_SELECT_REG);
                 }
         } else if (rq->flags & REQ_DRIVE_TASKFILE) {
- ide_task_t *args = (ide_task_t *) rq->special;
+ ata_request_t *ar = rq->special;
+ ide_task_t *args = &ar->ar_task;
                 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
+ if (args && args->taskfile.command == WIN_NOP)
+ printk("ide_end_drive_cmd: NOP completed\n");
                 if (args) {
                         args->taskfile.feature = err;
                         args->taskfile.sector_count = IN_BYTE(IDE_NSECTOR_REG);
@@ -762,6 +792,8 @@
                                 args->hobfile.high_cylinder = IN_BYTE(IDE_HCYL_REG);
                         }
                 }
+ if (ar->ar_flags & ATA_AR_RETURN)
+ ata_ar_put(drive, ar);
         }
 
         blkdev_dequeue_request(rq);
@@ -879,6 +911,11 @@
         struct request *rq;
         byte err;
 
+ /*
+ * FIXME: remember to invalidate tcq queue when drive->using_tcq
+ * and atomic_read(&drive->tcq->queued) /jens
+ */
+
         err = ide_dump_status(drive, msg, stat);
         if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
                 return ide_stopped;
@@ -1063,7 +1100,11 @@
         while ((read_timer() - hwif->last_time) < DISK_RECOVERY_TIME);
 #endif
 
+ if (test_bit(IDE_DMA, &HWGROUP(drive)->flags))
+ printk("start_request: auch, DMA in progress 1\n");
         SELECT_DRIVE(hwif, drive);
+ if (test_bit(IDE_DMA, &HWGROUP(drive)->flags))
+ printk("start_request: auch, DMA in progress 2\n");
         if (ide_wait_stat(&startstop, drive, drive->ready_stat,
                           BUSY_STAT|DRQ_STAT, WAIT_READY)) {
                 printk(KERN_WARNING "%s: drive not ready for command\n", drive->name);
@@ -1083,11 +1124,14 @@
                          */
 
                         if (rq->flags & REQ_DRIVE_TASKFILE) {
- ide_task_t *args = rq->special;
+ ata_request_t *ar = rq->special;
+ ide_task_t *args;
 
- if (!(args))
+ if (!ar)
                                         goto args_error;
 
+ args = &ar->ar_task;
+
                                 ata_taskfile(drive,
                                                 &args->taskfile,
                                                 &args->hobfile,
@@ -1321,16 +1365,37 @@
                 hwgroup->hwif = hwif;
                 hwgroup->drive = drive;
                 drive->PADAM_sleep = 0;
+queue_next:
                 drive->PADAM_service_start = jiffies;
 
- if (blk_queue_plugged(&drive->queue))
- BUG();
+ if (test_bit(IDE_DMA, &hwgroup->flags)) {
+ printk("ide_do_request: DMA in progress...\n");
+ break;
+ }
+
+ /*
+ * there's a small window between where the queue could be
+ * replugged while we are in here when using tcq (in which
+ * case the queue is probably empty anyways...), so check
+ * and leave if appropriate. When not using tcq, this is
+ * still a severe BUG!
+ */
+ if (blk_queue_plugged(&drive->queue)) {
+ BUG_ON(!drive->using_tcq);
+ break;
+ }
 
                 /*
                  * just continuing an interrupted request maybe
                  */
                 rq = hwgroup->rq = elv_next_request(&drive->queue);
 
+ if (!rq) {
+ if (!ide_pending_commands(drive))
+ clear_bit(IDE_BUSY, &HWGROUP(drive)->flags);
+ break;
+ }
+
                 /*
                  * Some systems have trouble with IDE IRQs arriving while
                  * the driver is still setting things up. So, here we disable
@@ -1341,14 +1406,22 @@
                  */
                 if (masked_irq && hwif->irq != masked_irq)
                         disable_irq_nosync(hwif->irq);
+
                 spin_unlock(&ide_lock);
                 ide__sti(); /* allow other IRQs while we start this request */
                 startstop = start_request(drive, rq);
+
                 spin_lock_irq(&ide_lock);
                 if (masked_irq && hwif->irq != masked_irq)
                         enable_irq(hwif->irq);
- if (startstop == ide_stopped)
+
+ if (startstop == ide_released)
+ goto queue_next;
+ else if (startstop == ide_stopped) {
+ if (test_bit(IDE_DMA, &hwgroup->flags))
+ printk("2nd illegal clear\n");
                         clear_bit(IDE_BUSY, &hwgroup->flags);
+ }
         }
 }
 
@@ -1375,21 +1448,39 @@
  * un-busy the hwgroup etc, and clear any pending DMA status. we want to
  * retry the current request in PIO mode instead of risking tossing it
  * all away
+ *
+ * FIXME: needs a bit of tcq work
  */
 void ide_dma_timeout_retry(ide_drive_t *drive)
 {
         struct ata_channel *hwif = drive->channel;
- struct request *rq;
+ struct request *rq = NULL;
+ ata_request_t *ar = NULL;
+
+ if (drive->using_tcq) {
+ if (drive->tcq->active_tag != -1) {
+ ar = IDE_CUR_AR(drive);
+ rq = ar->ar_rq;
+ }
+ } else {
+ rq = HWGROUP(drive)->rq;
+ ar = rq->special;
+ }
 
         /*
          * end current dma transaction
          */
- hwif->dmaproc(ide_dma_end, drive);
+ if (rq)
+ hwif->dmaproc(ide_dma_end, drive);
 
         /*
          * complain a little, later we might remove some of this verbosity
          */
- printk("%s: timeout waiting for DMA\n", drive->name);
+ printk("%s: timeout waiting for DMA", drive->name);
+ if (drive->using_tcq)
+ printk(" queued, active tag %d", drive->tcq->active_tag);
+ printk("\n");
+
         hwif->dmaproc(ide_dma_timeout, drive);
 
         /*
@@ -1405,15 +1496,25 @@
          * un-busy drive etc (hwgroup->busy is cleared on return) and
          * make sure request is sane
          */
- rq = HWGROUP(drive)->rq;
         HWGROUP(drive)->rq = NULL;
 
+ if (!rq)
+ return;
+
         rq->errors = 0;
         if (rq->bio) {
                 rq->sector = rq->bio->bi_sector;
                 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
                 rq->buffer = NULL;
         }
+
+ /*
+ * this request was not on the queue any more
+ */
+ if (ar->ar_flags & ATA_AR_QUEUED) {
+ ata_ar_put(drive, ar);
+ _elv_add_request(&drive->queue, rq, 0, 0);
+ }
 }
 
 /*
@@ -1643,8 +1744,10 @@
         set_recovery_timer(drive->channel);
         drive->PADAM_service_time = jiffies - drive->PADAM_service_start;
         if (startstop == ide_stopped) {
- if (hwgroup->handler == NULL) { /* paranoia */
+ if (hwgroup->handler == NULL) { /* paranoia */
                         clear_bit(IDE_BUSY, &hwgroup->flags);
+ if (test_bit(IDE_DMA, &hwgroup->flags))
+ printk("ide_intr: illegal clear\n");
                         ide_do_request(hwgroup, hwif->irq);
                 } else {
                         printk("%s: ide_intr: huh? expected NULL handler on exit\n", drive->name);
@@ -1724,6 +1827,7 @@
         if (drive->channel->chipset == ide_pdc4030 && rq->buffer != NULL)
                 return -ENOSYS; /* special drive cmds not supported */
 #endif
+ rq->flags |= REQ_STARTED;
         rq->errors = 0;
         rq->rq_status = RQ_ACTIVE;
         rq->rq_dev = mk_kdev(major,(drive->select.b.unit)<<PARTN_BITS);
@@ -2047,6 +2151,7 @@
                 }
                 drive->present = 0;
                 blk_cleanup_queue(&drive->queue);
+ ide_teardown_commandlist(drive);
         }
         if (d->present)
                 hwgroup->drive = d;
@@ -2597,6 +2702,87 @@
         }
 }
 
+void ide_teardown_commandlist(ide_drive_t *drive)
+{
+ struct pci_dev *pdev= drive->channel->pci_dev;
+ struct list_head *entry;
+
+ list_for_each(entry, &drive->free_req) {
+ ata_request_t *ar = list_ata_entry(entry);
+
+ list_del(&ar->ar_queue);
+ kfree(ar->ar_sg_table);
+ pci_free_consistent(pdev, PRD_SEGMENTS * PRD_BYTES, ar->ar_dmatable_cpu, ar->ar_dmatable);
+ kfree(ar);
+ }
+}
+
+int ide_build_commandlist(ide_drive_t *drive)
+{
+ struct pci_dev *pdev= drive->channel->pci_dev;
+ ata_request_t *ar;
+ ide_tag_info_t *tcq;
+ int i, err;
+
+ tcq = kmalloc(sizeof(ide_tag_info_t), GFP_ATOMIC);
+ if (!tcq)
+ return -ENOMEM;
+
+ drive->tcq = tcq;
+ memset(drive->tcq, 0, sizeof(ide_tag_info_t));
+
+ INIT_LIST_HEAD(&drive->free_req);
+ drive->using_tcq = 0;
+
+ err = -ENOMEM;
+ for (i = 0; i < drive->queue_depth; i++) {
+ ar = kmalloc(sizeof(ata_request_t), GFP_ATOMIC);
+ if (!ar)
+ break;
+
+ memset(ar, 0, sizeof(ar));
+ INIT_LIST_HEAD(&ar->ar_queue);
+
+ ar->ar_sg_table = kmalloc(PRD_SEGMENTS * sizeof(struct scatterlist), GFP_ATOMIC);
+ if (!ar->ar_sg_table) {
+ kfree(ar);
+ break;
+ }
+
+ ar->ar_dmatable_cpu = pci_alloc_consistent(pdev, PRD_SEGMENTS * PRD_BYTES, &ar->ar_dmatable);
+ if (!ar->ar_dmatable_cpu) {
+ kfree(ar->ar_sg_table);
+ kfree(ar);
+ break;
+ }
+
+
+
+ /*
+ * pheew, all done, add to list
+ */
+ list_add_tail(&ar->ar_queue, &drive->free_req);
+ }
+
+ if (i) {
+ drive->queue_depth = i;
+ if (i >= 1) {
+ drive->using_tcq = 1;
+ drive->tcq->queued = 0;
+ drive->tcq->active_tag = -1;
+ return 0;
+ }
+
+ kfree(drive->tcq);
+ drive->tcq = NULL;
+ err = 0;
+ }
+
+ kfree(drive->tcq);
+ drive->tcq = NULL;
+ return err;
+}
+
 static int ide_check_media_change (kdev_t i_rdev)
 {
         ide_drive_t *drive;
@@ -3154,6 +3340,9 @@
 
                         drive->channel->dmaproc(ide_dma_off_quietly, drive);
                         drive->channel->dmaproc(ide_dma_check, drive);
+#ifdef CONFIG_BLK_DEV_IDE_TCQ_DEFAULT
+ drive->channel->dmaproc(ide_dma_queued_on, drive);
+#endif /* CONFIG_BLK_DEV_IDE_TCQ_DEFAULT */
                 }
                 /* Only CD-ROMs and tape drives support DSC overlap. */
                 drive->dsc_overlap = (drive->next != drive
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/drivers/ide/pdc202xx.c linux/drivers/ide/pdc202xx.c
--- /opt/kernel/linux-2.5.8-pre2/drivers/ide/pdc202xx.c Tue Apr 9 11:41:13 2002
+++ linux/drivers/ide/pdc202xx.c Thu Apr 4 09:39:18 2002
@@ -1057,6 +1057,12 @@
                 case ide_dma_timeout:
                         if (drive->channel->resetproc != NULL)
                                 drive->channel->resetproc(drive);
+ /*
+ * we cannot support queued operations on promise, so fail to
+ * to enable it...
+ */
+ case ide_dma_queued_on:
+ return 1;
                 default:
                         break;
         }
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/include/linux/hdreg.h linux/include/linux/hdreg.h
--- /opt/kernel/linux-2.5.8-pre2/include/linux/hdreg.h Tue Apr 9 11:41:13 2002
+++ linux/include/linux/hdreg.h Thu Apr 4 08:14:18 2002
@@ -34,6 +34,7 @@
 #define ECC_STAT 0x04 /* Corrected error */
 #define DRQ_STAT 0x08
 #define SEEK_STAT 0x10
+#define SERVICE_STAT SEEK_STAT
 #define WRERR_STAT 0x20
 #define READY_STAT 0x40
 #define BUSY_STAT 0x80
@@ -50,6 +51,13 @@
 #define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */
 
 /*
+ * bits of NSECTOR reg
+ */
+#define NSEC_CD 0x1
+#define NSEC_IO 0x2
+#define NSEC_REL 0x4
+
+/*
  * Command Header sizes for IOCTL commands
  * HDIO_DRIVE_CMD and HDIO_DRIVE_TASK
  */
diff -urN -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.5.8-pre2/include/linux/ide.h linux/include/linux/ide.h
--- /opt/kernel/linux-2.5.8-pre2/include/linux/ide.h Tue Apr 9 11:41:13 2002
+++ linux/include/linux/ide.h Tue Apr 9 14:14:02 2002
@@ -13,7 +13,9 @@
 #include <linux/proc_fs.h>
 #include <linux/device.h>
 #include <linux/devfs_fs_kernel.h>
+#include <linux/interrupt.h>
 #include <asm/hdreg.h>
+#include <asm/bitops.h>
 
 /*
  * This is the multiple IDE interface driver, as evolved from hd.c.
@@ -111,6 +113,7 @@
 #define GET_ERR() IN_BYTE(IDE_ERROR_REG)
 #define GET_STAT() IN_BYTE(IDE_STATUS_REG)
 #define GET_ALTSTAT() IN_BYTE(IDE_CONTROL_REG)
+#define GET_FEAT() IN_BYTE(IDE_NSECTOR_REG)
 #define OK_STAT(stat,good,bad) (((stat)&((good)|(bad)))==(good))
 #define BAD_R_STAT (BUSY_STAT | ERR_STAT)
 #define BAD_W_STAT (BAD_R_STAT | WRERR_STAT)
@@ -132,6 +135,7 @@
  */
 #define PRD_BYTES 8
 #define PRD_ENTRIES (PAGE_SIZE / (2 * PRD_BYTES))
+#define PRD_SEGMENTS 32
 
 /*
  * Some more useful definitions
@@ -266,6 +270,39 @@
         } b;
 } special_t;
 
+#define IDE_MAX_TAG 32 /* spec says 32 max */
+
+struct ata_request_s;
+typedef struct ide_tag_info_s {
+ unsigned long tag_mask; /* next tag bit mask */
+ struct ata_request_s *ar[IDE_MAX_TAG]; /* in-progress requests */
+ int active_tag; /* current active tag */
+
+ int queued; /* current depth */
+
+ /*
+ * stats ->
+ */
+ int max_depth; /* max depth ever */
+
+ int max_last_depth; /* max since last check */
+
+ /*
+ * either the command complete immediately after being started
+ * (immed_comp), or the device did a bus release before dma was
+ * started (immed_rel)
+ */
+ int immed_rel;
+ int immed_comp;
+} ide_tag_info_t;
+
+#define IDE_GET_AR(drive, tag) ((drive)->tcq->ar[(tag)])
+#define IDE_CUR_TAG(drive) (IDE_GET_AR((drive), (drive)->tcq->active_tag))
+#define IDE_SET_CUR_TAG(drive, tag) ((drive)->tcq->active_tag = (tag))
+
+#define IDE_CUR_AR(drive) \
+ ((drive)->using_tcq ? IDE_CUR_TAG((drive)) : HWGROUP((drive))->rq->special)
+
 struct ide_settings_s;
 
 typedef struct ide_drive_s {
@@ -275,11 +312,13 @@
         char type; /* distingiush different devices: disk, cdrom, tape, floppy, ... */
 
         /* NOTE: If we had proper separation between channel and host chip, we
- * could move this to the chanell and many sync problems would
+ * could move this to the channel and many sync problems would
          * magically just go away.
          */
         request_queue_t queue; /* per device request queue */
 
+ struct list_head free_req; /* free ata requests */
+
         struct ide_drive_s *next; /* circular list of hwgroup drives */
 
         /* Those are directly injected jiffie values. They should go away and
@@ -294,6 +333,7 @@
         special_t special; /* special action flags */
         byte keep_settings; /* restore settings after drive reset */
         byte using_dma; /* disk is using dma for read/write */
+ byte using_tcq; /* disk is using queued dma operations*/
         byte retry_pio; /* retrying dma capable host in pio */
         byte state; /* retry state */
         byte unmask; /* flag: okay to unmask other irqs */
@@ -369,6 +409,8 @@
         unsigned int failures; /* current failure count */
         unsigned int max_failures; /* maximum allowed failure count */
         struct device device; /* global device tree handle */
+ unsigned int queue_depth;
+ ide_tag_info_t *tcq;
 } ide_drive_t;
 
 /*
@@ -387,7 +429,10 @@
                 ide_dma_off, ide_dma_off_quietly, ide_dma_test_irq,
                 ide_dma_bad_drive, ide_dma_good_drive,
                 ide_dma_verbose, ide_dma_retune,
- ide_dma_lostirq, ide_dma_timeout
+ ide_dma_lostirq, ide_dma_timeout,
+ ide_dma_read_queued, ide_dma_write_queued,
+ ide_dma_queued_start, ide_dma_queued_on,
+ ide_dma_queued_off,
 } ide_dma_action_t;
 
 typedef int (ide_dmaproc_t)(ide_dma_action_t, ide_drive_t *);
@@ -462,11 +507,6 @@
         ide_rw_proc_t *rwproc; /* adjust timing based upon rq->cmd direction */
         ide_ideproc_t *ideproc; /* CPU-polled transfer routine */
         ide_dmaproc_t *dmaproc; /* dma read/write/abort routine */
- unsigned int *dmatable_cpu; /* dma physical region descriptor table (cpu view) */
- dma_addr_t dmatable_dma; /* dma physical region descriptor table (dma view) */
- struct scatterlist *sg_table; /* Scatter-gather list used to build the above */
- int sg_nents; /* Current number of entries in it */
- int sg_dma_direction; /* dma transfer direction */
         struct ata_channel *mate; /* other hwif from same PCI chip */
         unsigned long dma_base; /* base addr for dma ports */
         unsigned dma_extra; /* extra addr for dma ports */
@@ -505,12 +545,14 @@
  */
 typedef enum {
         ide_stopped, /* no drive operation was started */
- ide_started /* a drive operation was started, and a handler was set */
+ ide_started, /* a drive operation was started, and a handler was set */
+ ide_released, /* started and released bus */
 } ide_startstop_t;
 
 /*
  * internal ide interrupt handler type
  */
+struct ide_task_s;
 typedef ide_startstop_t (ide_pre_handler_t)(ide_drive_t *, struct request *);
 typedef ide_startstop_t (ide_handler_t)(ide_drive_t *);
 typedef ide_startstop_t (ide_post_handler_t)(ide_drive_t *);
@@ -521,8 +563,9 @@
  */
 typedef int (ide_expiry_t)(ide_drive_t *);
 
-#define IDE_BUSY 0
+#define IDE_BUSY 0 /* hwgroup busy */
 #define IDE_SLEEP 1
+#define IDE_DMA 2 /* DMA in progress */
 
 typedef struct hwgroup_s {
         ide_handler_t *handler;/* irq handler, if active */
@@ -674,6 +717,7 @@
 
 extern int __ide_end_request(ide_drive_t *drive, int uptodate, int nr_secs);
 extern int ide_end_request(ide_drive_t *drive, int uptodate);
+extern void ide_end_queued_request(ide_drive_t *drive, int, struct request *);
 
 /*
  * This is used on exit from the driver, to designate the next irq handler
@@ -739,6 +783,7 @@
  * This function is intended to be used prior to invoking ide_do_drive_cmd().
  */
 void ide_init_drive_cmd (struct request *rq);
+void init_taskfile_request(struct request *rq);
 
 /*
  * "action" parameter type for ide_do_drive_cmd() below.
@@ -768,8 +813,37 @@
         int command_type;
         ide_pre_handler_t *prehandler;
         ide_handler_t *handler;
+ struct ata_request_s *ar;
 } ide_task_t;
 
+/*
+ * wrap this on top of struct request
+ */
+typedef struct ata_request_s {
+ struct request *ar_rq; /* real request */
+ struct ide_drive_s *ar_drive; /* associated drive */
+ unsigned long ar_flags; /* ATA_AR_* flags */
+ int ar_tag; /* tag number, if any */
+ struct list_head ar_queue; /* pending list */
+ ide_task_t ar_task; /* associated taskfile */
+ unsigned long ar_time;
+
+ /*
+ * dma stuff, pci layer
+ */
+ struct scatterlist *ar_sg_table;
+ int ar_sg_nents;
+ int ar_sg_ddir;
+
+ /*
+ * cpu dma stuff
+ */
+ unsigned int *ar_dmatable_cpu;
+ dma_addr_t ar_dmatable;
+} ata_request_t;
+
+#define AR_TASK_CMD(ar) ((ar)->ar_task.taskfile.command)
+
 void ata_input_data (ide_drive_t *drive, void *buffer, unsigned int wcount);
 void ata_output_data (ide_drive_t *drive, void *buffer, unsigned int wcount);
 void atapi_input_bytes (ide_drive_t *drive, void *buffer, unsigned int bytecount);
@@ -886,8 +960,9 @@
 void __init ide_scan_pcibus(int scan_direction);
 #endif
 #ifdef CONFIG_BLK_DEV_IDEDMA
-int ide_build_dmatable (ide_drive_t *drive, ide_dma_action_t func);
+int ide_build_dmatable (ide_drive_t *drive, struct request *rq, ide_dma_action_t func);
 void ide_destroy_dmatable (ide_drive_t *drive);
+int ide_start_dma(struct ata_channel *, ide_drive_t *, ide_dma_action_t);
 ide_startstop_t ide_dma_intr (ide_drive_t *drive);
 int check_drive_lists (ide_drive_t *drive, int good_bad);
 int ide_dmaproc (ide_dma_action_t func, ide_drive_t *drive);
@@ -898,7 +973,102 @@
 
 extern spinlock_t ide_lock;
 
+#define DRIVE_LOCK(drive) ((drive)->queue.queue_lock)
+
 extern int drive_is_ready(ide_drive_t *drive);
 extern void revalidate_drives(void);
 
+/*
+ * TCQ stuff...
+ */
+/*
+ * ata_request_ flag bits
+ */
+#define ATA_AR_QUEUED 1
+#define ATA_AR_SETUP 2
+#define ATA_AR_RETURN 4
+
+#define list_ata_entry(entry) list_entry((entry), ata_request_t, ar_queue)
+
+#define IDE_SET_TAG(drive, ar, tag) do { \
+ (ar)->ar_flags |= ATA_AR_QUEUED; \
+ (ar)->ar_tag = (tag); \
+ (drive)->tcq->ar[(tag)] = (ar); \
+ (drive)->tcq->active_tag = (tag); \
+ (ar)->ar_time = jiffies; \
+ (drive)->tcq->queued++; \
+} while (0)
+
+#define IDE_CLEAR_TAG(drive, tag) do { \
+ (drive)->tcq->ar[(tag)] = NULL; \
+ __clear_bit((tag), &(drive)->tcq->tag_mask); \
+ (drive)->tcq->queued--; \
+} while (0)
+
+#define ATA_AR_INIT(drive, ar) do { \
+ (ar)->ar_rq = NULL; \
+ (ar)->ar_drive = (drive); \
+ (ar)->ar_flags = 0; \
+ (ar)->ar_tag = 0; \
+ memset(&(ar)->ar_task, 0, sizeof(ide_task_t)); \
+ (ar)->ar_sg_nents = 0; \
+ (ar)->ar_sg_ddir = 0; \
+} while (0)
+
+/*
+ * return a free command, automatically add it to busy list
+ */
+extern inline ata_request_t *ata_ar_get(ide_drive_t *drive)
+{
+ ata_request_t *ar = NULL;
+
+ if (drive->tcq && drive->tcq->queued >= drive->queue_depth)
+ return NULL;
+
+ if (!list_empty(&drive->free_req)) {
+ ar = list_ata_entry(drive->free_req.next);
+ list_del(&ar->ar_queue);
+ ATA_AR_INIT(drive, ar);
+ }
+
+ return ar;
+}
+
+extern inline void ata_ar_put(ide_drive_t *drive, ata_request_t *ar)
+{
+ list_add(&ar->ar_queue, &drive->free_req);
+
+ if (ar->ar_flags & ATA_AR_QUEUED)
+ IDE_CLEAR_TAG(drive, ar->ar_tag);
+
+ ar->ar_rq = NULL;
+}
+
+extern inline int ide_get_tag(ide_drive_t *drive)
+{
+ int tag = ffz(drive->tcq->tag_mask);
+
+ BUG_ON(drive->tcq->tag_mask == 0xffffffff);
+
+ __set_bit(tag, &drive->tcq->tag_mask);
+
+ if (tag + 1 > drive->tcq->max_depth)
+ drive->tcq->max_depth = tag + 1;
+ if (tag + 1 > drive->tcq->max_last_depth)
+ drive->tcq->max_last_depth = tag + 1;
+
+ return tag;
+}
+
+#ifdef CONFIG_BLK_DEV_IDE_TCQ
+#define ide_pending_commands(drive) ((drive)->using_tcq && (drive)->tcq->queued)
+#else
+#define ide_pending_commands(drive) 0
+#endif
+
+int ide_build_commandlist(ide_drive_t *);
+void ide_teardown_commandlist(ide_drive_t *);
+int ide_tcq_dmaproc(ide_dma_action_t, ide_drive_t *);
+ide_startstop_t ide_start_tag(ide_dma_action_t, ide_drive_t *, ata_request_t *);
+
 #endif /* _IDE_H */

-- 
Jens Axboe

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This archive was generated by hypermail 2b29 : Mon Apr 15 2002 - 22:00:13 EST