29 files changed, 226 insertions, 78 deletions

diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index a7a099027fca..014e72121b5a 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -31,4 +31,4 @@ obj-$(CONFIG_BLK_DEV_SX8)	+= sx8.o
 obj-$(CONFIG_BLK_DEV_UB)	+= ub.o
 
 obj-$(CONFIG_XEN_BLKDEV_FRONTEND)	+= xen-blkfront.o
-obj-$(CONFIG_LGUEST_GUEST)	+= lguest_blk.o
+obj-$(CONFIG_LGUEST_BLOCK)	+= lguest_blk.o
diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 6ce8b897e262..c9751b2b57e6 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -1422,7 +1422,7 @@ static void redo_fd_request(void)
 	goto repeat;
 }
 
-static void do_fd_request(request_queue_t * q)
+static void do_fd_request(struct request_queue * q)
 {
 	redo_fd_request();
 }
diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 1d8466817943..ba07f762c4cb 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -138,7 +138,7 @@ struct aoedev {
 	u16 maxbcnt;
 	struct work_struct work;/* disk create work struct */
 	struct gendisk *gd;
-	request_queue_t blkq;
+	struct request_queue blkq;
 	struct hd_geometry geo; 
 	sector_t ssize;
 	struct timer_list timer;
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 4f598270fa31..007faaf008e7 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -125,7 +125,7 @@ aoeblk_release(struct inode *inode, struct file *filp)
 }
 
 static int
-aoeblk_make_request(request_queue_t *q, struct bio *bio)
+aoeblk_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct aoedev *d;
 	struct buf *buf;
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 14d6b9492750..94268c75d04f 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1466,7 +1466,7 @@ repeat:
 }
 
 
-void do_fd_request(request_queue_t * q)
+void do_fd_request(struct request_queue * q)
 {
  	unsigned long flags;
 
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index a2d6612b80d2..a11b2bd54bbe 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -139,7 +139,7 @@ static struct board_type products[] = {
 
 static ctlr_info_t *hba[MAX_CTLR];
 
-static void do_cciss_request(request_queue_t *q);
+static void do_cciss_request(struct request_queue *q);
 static irqreturn_t do_cciss_intr(int irq, void *dev_id);
 static int cciss_open(struct inode *inode, struct file *filep);
 static int cciss_release(struct inode *inode, struct file *filep);
@@ -1584,7 +1584,7 @@ static int deregister_disk(struct gendisk *disk, drive_info_struct *drv,
 	 */
 	if (h->gendisk[0] != disk) {
 		if (disk) {
-			request_queue_t *q = disk->queue;
+			struct request_queue *q = disk->queue;
 			if (disk->flags & GENHD_FL_UP)
 				del_gendisk(disk);
 			if (q) {
@@ -2511,7 +2511,7 @@ after_error_processing:
 /*
  * Get a request and submit it to the controller.
  */
-static void do_cciss_request(request_queue_t *q)
+static void do_cciss_request(struct request_queue *q)
 {
 	ctlr_info_t *h = q->queuedata;
 	CommandList_struct *c;
@@ -3227,12 +3227,15 @@ static int alloc_cciss_hba(void)
 	for (i = 0; i < MAX_CTLR; i++) {
 		if (!hba[i]) {
 			ctlr_info_t *p;
+
 			p = kzalloc(sizeof(ctlr_info_t), GFP_KERNEL);
 			if (!p)
 				goto Enomem;
 			p->gendisk[0] = alloc_disk(1 << NWD_SHIFT);
-			if (!p->gendisk[0])
+			if (!p->gendisk[0]) {
+				kfree(p);
 				goto Enomem;
+			}
 			hba[i] = p;
 			return i;
 		}
@@ -3380,7 +3383,7 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
 	do {
 		drive_info_struct *drv = &(hba[i]->drv[j]);
 		struct gendisk *disk = hba[i]->gendisk[j];
-		request_queue_t *q;
+		struct request_queue *q;
 
 		/* Check if the disk was allocated already */
 		if (!disk){
@@ -3523,7 +3526,7 @@ static void __devexit cciss_remove_one(struct pci_dev *pdev)
 	for (j = 0; j < CISS_MAX_LUN; j++) {
 		struct gendisk *disk = hba[i]->gendisk[j];
 		if (disk) {
-			request_queue_t *q = disk->queue;
+			struct request_queue *q = disk->queue;
 
 			if (disk->flags & GENHD_FL_UP)
 				del_gendisk(disk);
diff --git a/drivers/block/cpqarray.c b/drivers/block/cpqarray.c
index b94cd1c32131..be4e3477d83b 100644
--- a/drivers/block/cpqarray.c
+++ b/drivers/block/cpqarray.c
@@ -161,7 +161,7 @@ static int ida_ioctl(struct inode *inode, struct file *filep, unsigned int cmd,
 static int ida_getgeo(struct block_device *bdev, struct hd_geometry *geo);
 static int ida_ctlr_ioctl(ctlr_info_t *h, int dsk, ida_ioctl_t *io);
 
-static void do_ida_request(request_queue_t *q);
+static void do_ida_request(struct request_queue *q);
 static void start_io(ctlr_info_t *h);
 
 static inline void addQ(cmdlist_t **Qptr, cmdlist_t *c);
@@ -391,7 +391,7 @@ static void __devexit cpqarray_remove_one_eisa (int i)
 /* pdev is NULL for eisa */
 static int __init cpqarray_register_ctlr( int i, struct pci_dev *pdev)
 {
-	request_queue_t *q;
+	struct request_queue *q;
 	int j;
 
 	/* 
@@ -886,7 +886,7 @@ static inline cmdlist_t *removeQ(cmdlist_t **Qptr, cmdlist_t *c)
  * are in here (either via the dummy do_ida_request functions or by being
  * called from the interrupt handler
  */
-static void do_ida_request(request_queue_t *q)
+static void do_ida_request(struct request_queue *q)
 {
 	ctlr_info_t *h = q->queuedata;
 	cmdlist_t *c;
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index fe088045dd08..085b7794fb3e 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -251,7 +251,7 @@ static int irqdma_allocated;
 
 static struct request *current_req;
 static struct request_queue *floppy_queue;
-static void do_fd_request(request_queue_t * q);
+static void do_fd_request(struct request_queue * q);
 
 #ifndef fd_get_dma_residue
 #define fd_get_dma_residue() get_dma_residue(FLOPPY_DMA)
@@ -2981,7 +2981,7 @@ static void process_fd_request(void)
 	schedule_bh(redo_fd_request);
 }
 
-static void do_fd_request(request_queue_t * q)
+static void do_fd_request(struct request_queue * q)
 {
 	if (max_buffer_sectors == 0) {
 		printk("VFS: do_fd_request called on non-open device\n");
diff --git a/drivers/block/lguest_blk.c b/drivers/block/lguest_blk.c
index 1634c2dd25ec..93e3c4001bf5 100644
--- a/drivers/block/lguest_blk.c
+++ b/drivers/block/lguest_blk.c
@@ -1,6 +1,12 @@
-/* A simple block driver for lguest.
+/*D:400
+ * The Guest block driver
  *
- * Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
+ * This is a simple block driver, which appears as /dev/lgba, lgbb, lgbc etc.
+ * The mechanism is simple: we place the information about the request in the
+ * device page, then use SEND_DMA (containing the data for a write, or an empty
+ * "ping" DMA for a read).
+ :*/
+/* Copyright 2006 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,27 +31,50 @@
 
 static char next_block_index = 'a';
 
+/*D:420 Here is the structure which holds all the information we need about
+ * each Guest block device.
+ *
+ * I'm sure at this stage, you're wondering "hey, where was the adventure I was
+ * promised?" and thinking "Rusty sucks, I shall say nasty things about him on
+ * my blog".  I think Real adventures have boring bits, too, and you're in the
+ * middle of one.  But it gets better.  Just not quite yet. */
 struct blockdev
 {
+	/* The block queue infrastructure wants a spinlock: it is held while it
+	 * calls our block request function.  We grab it in our interrupt
+	 * handler so the responses don't mess with new requests. */
 	spinlock_t lock;
 
-	/* The disk structure for the kernel. */
+	/* The disk structure registered with kernel. */
 	struct gendisk *disk;
 
-	/* The major number for this disk. */
+	/* The major device number for this disk, and the interrupt.  We only
+	 * really keep them here for completeness; we'd need them if we
+	 * supported device unplugging. */
 	int major;
 	int irq;
 
+	/* The physical address of this device's memory page */
 	unsigned long phys_addr;
-	/* The mapped block page. */
+	/* The mapped memory page for convenient acces. */
 	struct lguest_block_page *lb_page;
 
-	/* We only have a single request outstanding at a time. */
+	/* We only have a single request outstanding at a time: this is it. */
 	struct lguest_dma dma;
 	struct request *req;
 };
 
-/* Jens gave me this nice helper to end all chunks of a request. */
+/*D:495 We originally used end_request() throughout the driver, but it turns
+ * out that end_request() is deprecated, and doesn't actually end the request
+ * (which seems like a good reason to deprecate it!).  It simply ends the first
+ * bio.  So if we had 3 bios in a "struct request" we would do all 3,
+ * end_request(), do 2, end_request(), do 1 and end_request(): twice as much
+ * work as we needed to do.
+ *
+ * This reinforced to me that I do not understand the block layer.
+ *
+ * Nonetheless, Jens Axboe gave me this nice helper to end all chunks of a
+ * request.  This improved disk speed by 130%. */
 static void end_entire_request(struct request *req, int uptodate)
 {
 	if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
@@ -55,30 +84,62 @@ static void end_entire_request(struct request *req, int uptodate)
 	end_that_request_last(req, uptodate);
 }
 
+/* I'm told there are only two stories in the world worth telling: love and
+ * hate.  So there used to be a love scene here like this:
+ *
+ *  Launcher:	We could make beautiful I/O together, you and I.
+ *  Guest:	My, that's a big disk!
+ *
+ * Unfortunately, it was just too raunchy for our otherwise-gentle tale. */
+
+/*D:490 This is the interrupt handler, called when a block read or write has
+ * been completed for us. */
 static irqreturn_t lgb_irq(int irq, void *_bd)
 {
+	/* We handed our "struct blockdev" as the argument to request_irq(), so
+	 * it is passed through to us here.  This tells us which device we're
+	 * dealing with in case we have more than one. */
 	struct blockdev *bd = _bd;
 	unsigned long flags;
 
+	/* We weren't doing anything?  Strange, but could happen if we shared
+	 * interrupts (we don't!). */
 	if (!bd->req) {
 		pr_debug("No work!\n");
 		return IRQ_NONE;
 	}
 
+	/* Not done yet?  That's equally strange. */
 	if (!bd->lb_page->result) {
 		pr_debug("No result!\n");
 		return IRQ_NONE;
 	}
 
+	/* We have to grab the lock before ending the request. */
 	spin_lock_irqsave(&bd->lock, flags);
+	/* "result" is 1 for success, 2 for failure: end_entire_request() wants
+	 * to know whether this succeeded or not. */
 	end_entire_request(bd->req, bd->lb_page->result == 1);
+	/* Clear out request, it's done. */
 	bd->req = NULL;
+	/* Reset incoming DMA for next time. */
 	bd->dma.used_len = 0;
+	/* Ready for more reads or writes */
 	blk_start_queue(bd->disk->queue);
 	spin_unlock_irqrestore(&bd->lock, flags);
+
+	/* The interrupt was for us, we dealt with it. */
 	return IRQ_HANDLED;
 }
 
+/*D:480 The block layer's "struct request" contains a number of "struct bio"s,
+ * each of which contains "struct bio_vec"s, each of which contains a page, an
+ * offset and a length.
+ *
+ * Fortunately there are iterators to help us walk through the "struct
+ * request".  Even more fortunately, there were plenty of places to steal the
+ * code from.  We pack the "struct request" into our "struct lguest_dma" and
+ * return the total length. */
 static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
 {
 	unsigned int i = 0, idx, len = 0;
@@ -87,8 +148,13 @@ static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
 	rq_for_each_bio(bio, req) {
 		struct bio_vec *bvec;
 		bio_for_each_segment(bvec, bio, idx) {
+			/* We told the block layer not to give us too many. */
 			BUG_ON(i == LGUEST_MAX_DMA_SECTIONS);
+			/* If we had a zero-length segment, it would look like
+			 * the end of the data referred to by the "struct
+			 * lguest_dma", so make sure that doesn't happen. */
 			BUG_ON(!bvec->bv_len);
+			/* Convert page & offset to a physical address */
 			dma->addr[i] = page_to_phys(bvec->bv_page)
 				+ bvec->bv_offset;
 			dma->len[i] = bvec->bv_len;
@@ -96,26 +162,39 @@ static unsigned int req_to_dma(struct request *req, struct lguest_dma *dma)
 			i++;
 		}
 	}
+	/* If the array isn't full, we mark the end with a 0 length */
 	if (i < LGUEST_MAX_DMA_SECTIONS)
 		dma->len[i] = 0;
 	return len;
 }
 
+/* This creates an empty DMA, useful for prodding the Host without sending data
+ * (ie. when we want to do a read) */
 static void empty_dma(struct lguest_dma *dma)
 {
 	dma->len[0] = 0;
 }
 
+/*D:470 Setting up a request is fairly easy: */
 static void setup_req(struct blockdev *bd,
 		      int type, struct request *req, struct lguest_dma *dma)
 {
+	/* The type is 1 (write) or 0 (read). */
 	bd->lb_page->type = type;
+	/* The sector on disk where the read or write starts. */
 	bd->lb_page->sector = req->sector;
+	/* The result is initialized to 0 (unfinished). */
 	bd->lb_page->result = 0;
+	/* The current request (so we can end it in the interrupt handler). */
 	bd->req = req;
+	/* The number of bytes: returned as a side-effect of req_to_dma(),
+	 * which packs the block layer's "struct request" into our "struct
+	 * lguest_dma" */
 	bd->lb_page->bytes = req_to_dma(req, dma);
 }
 
+/*D:450 Write is pretty straightforward: we pack the request into a "struct
+ * lguest_dma", then use SEND_DMA to send the request. */
 static void do_write(struct blockdev *bd, struct request *req)
 {
 	struct lguest_dma send;
@@ -126,6 +205,9 @@ static void do_write(struct blockdev *bd, struct request *req)
 	lguest_send_dma(bd->phys_addr, &send);
 }
 
+/* Read is similar to write, except we pack the request into our receive
+ * "struct lguest_dma" and send through an empty DMA just to tell the Host that
+ * there's a request pending. */
 static void do_read(struct blockdev *bd, struct request *req)
 {
 	struct lguest_dma ping;
@@ -137,21 +219,30 @@ static void do_read(struct blockdev *bd, struct request *req)
 	lguest_send_dma(bd->phys_addr, &ping);
 }
 
-static void do_lgb_request(request_queue_t *q)
+/*D:440 This where requests come in: we get handed the request queue and are
+ * expected to pull a "struct request" off it until we've finished them or
+ * we're waiting for a reply: */
+static void do_lgb_request(struct request_queue *q)
 {
 	struct blockdev *bd;
 	struct request *req;
 
 again:
+	/* This sometimes returns NULL even on the very first time around.  I
+	 * wonder if it's something to do with letting elves handle the request
+	 * queue... */
 	req = elv_next_request(q);
 	if (!req)
 		return;
 
+	/* We attached the struct blockdev to the disk: get it back */
 	bd = req->rq_disk->private_data;
-	/* Sometimes we get repeated requests after blk_stop_queue. */
+	/* Sometimes we get repeated requests after blk_stop_queue(), but we
+	 * can only handle one at a time. */
 	if (bd->req)
 		return;
 
+	/* We only do reads and writes: no tricky business! */
 	if (!blk_fs_request(req)) {
 		pr_debug("Got non-command 0x%08x\n", req->cmd_type);
 		req->errors++;
@@ -164,20 +255,31 @@ again:
 	else
 		do_read(bd, req);
 
-	/* Wait for interrupt to tell us it's done. */
+	/* We've put out the request, so stop any more coming in until we get
+	 * an interrupt, which takes us to lgb_irq() to re-enable the queue. */
 	blk_stop_queue(q);
 }
 
+/*D:430 This is the "struct block_device_operations" we attach to the disk at
+ * the end of lguestblk_probe().  It doesn't seem to want much. */
 static struct block_device_operations lguestblk_fops = {
 	.owner = THIS_MODULE,
 };
 
+/*D:425 Setting up a disk device seems to involve a lot of code.  I'm not sure
+ * quite why.  I do know that the IDE code sent two or three of the maintainers
+ * insane, perhaps this is the fringe of the same disease?
+ *
+ * As in the console code, the probe function gets handed the generic
+ * lguest_device from lguest_bus.c: */
 static int lguestblk_probe(struct lguest_device *lgdev)
 {
 	struct blockdev *bd;
 	int err;
 	int irqflags = IRQF_SHARED;
 
+	/* First we allocate our own "struct blockdev" and initialize the easy
+	 * fields. */
 	bd = kmalloc(sizeof(*bd), GFP_KERNEL);
 	if (!bd)
 		return -ENOMEM;
@@ -187,59 +289,100 @@ static int lguestblk_probe(struct lguest_device *lgdev)
 	bd->req = NULL;
 	bd->dma.used_len = 0;
 	bd->dma.len[0] = 0;
+	/* The descriptor in the lguest_devices array provided by the Host
+	 * gives the Guest the physical page number of the device's page. */
 	bd->phys_addr = (lguest_devices[lgdev->index].pfn << PAGE_SHIFT);
 
+	/* We use lguest_map() to get a pointer to the device page */
 	bd->lb_page = lguest_map(bd->phys_addr, 1);
 	if (!bd->lb_page) {
 		err = -ENOMEM;
 		goto out_free_bd;
 	}
 
+	/* We need a major device number: 0 means "assign one dynamically". */
 	bd->major = register_blkdev(0, "lguestblk");
 	if (bd->major < 0) {
 		err = bd->major;
 		goto out_unmap;
 	}
 
+	/* This allocates a "struct gendisk" where we pack all the information
+	 * about the disk which the rest of Linux sees.  We ask for one minor
+	 * number; I do wonder if we should be asking for more. */
 	bd->disk = alloc_disk(1);
 	if (!bd->disk) {
 		err = -ENOMEM;
 		goto out_unregister_blkdev;
 	}
 
+	/* Every disk needs a queue for requests to come in: we set up the
+	 * queue with a callback function (the core of our driver) and the lock
+	 * to use. */
 	bd->disk->queue = blk_init_queue(do_lgb_request, &bd->lock);
 	if (!bd->disk->queue) {
 		err = -ENOMEM;
 		goto out_put_disk;
 	}
 
-	/* We can only handle a certain number of sg entries */
+	/* We can only handle a certain number of pointers in our SEND_DMA
+	 * call, so we set that with blk_queue_max_hw_segments().  This is not
+	 * to be confused with blk_queue_max_phys_segments() of course!  I
+	 * know, who could possibly confuse the two?
+	 *
+	 * Well, it's simple to tell them apart: this one seems to work and the
+	 * other one didn't. */
 	blk_queue_max_hw_segments(bd->disk->queue, LGUEST_MAX_DMA_SECTIONS);
-	/* Buffers must not cross page boundaries */
+
+	/* Due to technical limitations of our Host (and simple coding) we
+	 * can't have a single buffer which crosses a page boundary.  Tell it
+	 * here.  This means that our maximum request size is 16
+	 * (LGUEST_MAX_DMA_SECTIONS) pages. */
 	blk_queue_segment_boundary(bd->disk->queue, PAGE_SIZE-1);
 
+	/* We name our disk: this becomes the device name when udev does its
+	 * magic thing and creates the device node, such as /dev/lgba.
+	 * next_block_index is a global which starts at 'a'.  Unfortunately
+	 * this simple increment logic means that the 27th disk will be called
+	 * "/dev/lgb{".  In that case, I recommend having at least 29 disks, so
+	 * your /dev directory will be balanced. */
 	sprintf(bd->disk->disk_name, "lgb%c", next_block_index++);
+
+	/* We look to the device descriptor again to see if this device's
+	 * interrupts are expected to be random.  If they are, we tell the irq
+	 * subsystem.  At the moment this bit is always set. */
 	if (lguest_devices[lgdev->index].features & LGUEST_DEVICE_F_RANDOMNESS)
 		irqflags |= IRQF_SAMPLE_RANDOM;
+
+	/* Now we have the name and irqflags, we can request the interrupt; we
+	 * give it the "struct blockdev" we have set up to pass to lgb_irq()
+	 * when there is an interrupt. */
 	err = request_irq(bd->irq, lgb_irq, irqflags, bd->disk->disk_name, bd);
 	if (err)
 		goto out_cleanup_queue;
 
+	/* We bind our one-entry DMA pool to the key for this block device so
+	 * the Host can reply to our requests.  The key is equal to the
+	 * physical address of the device's page, which is conveniently
+	 * unique. */
 	err = lguest_bind_dma(bd->phys_addr, &bd->dma, 1, bd->irq);
 	if (err)
 		goto out_free_irq;
 
+	/* We finish our disk initialization and add the disk to the system. */
 	bd->disk->major = bd->major;
 	bd->disk->first_minor = 0;
 	bd->disk->private_data = bd;
 	bd->disk->fops = &lguestblk_fops;
-	/* This is initialized to the disk size by the other end. */
+	/* This is initialized to the disk size by the Launcher. */
 	set_capacity(bd->disk, bd->lb_page->num_sectors);
 	add_disk(bd->disk);
 
 	printk(KERN_INFO "%s: device %i at major %d\n",
 	       bd->disk->disk_name, lgdev->index, bd->major);
 
+	/* We don't need to keep the "struct blockdev" around, but if we ever
+	 * implemented device removal, we'd need this. */
 	lgdev->private = bd;
 	return 0;
 
@@ -258,6 +401,8 @@ out_free_bd:
 	return err;
 }
 
+/*D:410 The boilerplate code for registering the lguest block driver is just
+ * like the console: */
 static struct lguest_driver lguestblk_drv = {
 	.name = "lguestblk",
 	.owner = THIS_MODULE,
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index e425daa1eac3..9f015fce4135 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -529,7 +529,7 @@ static struct bio *loop_get_bio(struct loop_device *lo)
 	return bio;
 }
 
-static int loop_make_request(request_queue_t *q, struct bio *old_bio)
+static int loop_make_request(struct request_queue *q, struct bio *old_bio)
 {
 	struct loop_device *lo = q->queuedata;
 	int rw = bio_rw(old_bio);
@@ -558,7 +558,7 @@ out:
 /*
  * kick off io on the underlying address space
  */
-static void loop_unplug(request_queue_t *q)
+static void loop_unplug(struct request_queue *q)
 {
 	struct loop_device *lo = q->queuedata;
 
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index c12951024090..be92c658f06e 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -100,7 +100,7 @@ static const char *nbdcmd_to_ascii(int cmd)
 static void nbd_end_request(struct request *req)
 {
 	int uptodate = (req->errors == 0) ? 1 : 0;
-	request_queue_t *q = req->q;
+	struct request_queue *q = req->q;
 	unsigned long flags;
 
 	dprintk(DBG_BLKDEV, "%s: request %p: %s\n", req->rq_disk->disk_name,
@@ -410,7 +410,7 @@ static void nbd_clear_que(struct nbd_device *lo)
  *   { printk( "Warning: Ignoring result!\n"); nbd_end_request( req ); }
  */
 
-static void do_nbd_request(request_queue_t * q)
+static void do_nbd_request(struct request_queue * q)
 {
 	struct request *req;
 	
diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index 1eeb8f2cde71..b8a994a2b013 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -183,7 +183,7 @@ static int pcd_packet(struct cdrom_device_info *cdi,
 static int pcd_detect(void);
 static void pcd_probe_capabilities(void);
 static void do_pcd_read_drq(void);
-static void do_pcd_request(request_queue_t * q);
+static void do_pcd_request(struct request_queue * q);
 static void do_pcd_read(void);
 
 struct pcd_unit {
@@ -713,7 +713,7 @@ static int pcd_detect(void)
 /* I/O request processing */
 static struct request_queue *pcd_queue;
 
-static void do_pcd_request(request_queue_t * q)
+static void do_pcd_request(struct request_queue * q)
 {
 	if (pcd_busy)
 		return;
diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c
index 31e01488eb51..df819f8a95a6 100644
--- a/drivers/block/paride/pd.c
+++ b/drivers/block/paride/pd.c
@@ -698,7 +698,7 @@ static enum action pd_identify(struct pd_unit *disk)
 
 /* end of io request engine */
 
-static void do_pd_request(request_queue_t * q)
+static void do_pd_request(struct request_queue * q)
 {
 	if (pd_req)
 		return;
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c
index 5826508f6731..ceffa6034e20 100644
--- a/drivers/block/paride/pf.c
+++ b/drivers/block/paride/pf.c
@@ -202,7 +202,7 @@ module_param_array(drive3, int, NULL, 0);
 #define ATAPI_WRITE_10		0x2a
 
 static int pf_open(struct inode *inode, struct file *file);
-static void do_pf_request(request_queue_t * q);
+static void do_pf_request(struct request_queue * q);
 static int pf_ioctl(struct inode *inode, struct file *file,
 		    unsigned int cmd, unsigned long arg);
 static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo);
@@ -760,7 +760,7 @@ static void pf_end_request(int uptodate)
 	}
 }
 
-static void do_pf_request(request_queue_t * q)
+static void do_pf_request(struct request_queue * q)
 {
 	if (pf_busy)
 		return;
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 31be33e4f119..fadbfd880bab 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -752,7 +752,7 @@ static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio
  */
 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 {
-	request_queue_t *q = bdev_get_queue(pd->bdev);
+	struct request_queue *q = bdev_get_queue(pd->bdev);
 	struct request *rq;
 	int ret = 0;
 
@@ -979,7 +979,7 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
  * Special care is needed if the underlying block device has a small
  * max_phys_segments value.
  */
-static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
+static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 {
 	if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 		/*
@@ -2314,7 +2314,7 @@ static int pkt_open_dev(struct pktcdvd_device *pd, int write)
 {
 	int ret;
 	long lba;
-	request_queue_t *q;
+	struct request_queue *q;
 
 	/*
 	 * We need to re-open the cdrom device without O_NONBLOCK to be able
@@ -2477,7 +2477,7 @@ static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int
 	return 0;
 }
 
-static int pkt_make_request(request_queue_t *q, struct bio *bio)
+static int pkt_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct pktcdvd_device *pd;
 	char b[BDEVNAME_SIZE];
@@ -2626,7 +2626,7 @@ end_io:
 
 
 
-static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
+static int pkt_merge_bvec(struct request_queue *q, struct bio *bio, struct bio_vec *bvec)
 {
 	struct pktcdvd_device *pd = q->queuedata;
 	sector_t zone = ZONE(bio->bi_sector, pd);
@@ -2647,7 +2647,7 @@ static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *b
 
 static void pkt_init_queue(struct pktcdvd_device *pd)
 {
-	request_queue_t *q = pd->disk->queue;
+	struct request_queue *q = pd->disk->queue;
 
 	blk_queue_make_request(q, pkt_make_request);
 	blk_queue_hardsect_size(q, CD_FRAMESIZE);
diff --git a/drivers/block/ps2esdi.c b/drivers/block/ps2esdi.c
index 688a4fb0dc99..3c796e236253 100644
--- a/drivers/block/ps2esdi.c
+++ b/drivers/block/ps2esdi.c
@@ -64,7 +64,7 @@ static void reset_ctrl(void);
 
 static int ps2esdi_geninit(void);
 
-static void do_ps2esdi_request(request_queue_t * q);
+static void do_ps2esdi_request(struct request_queue * q);
 
 static void ps2esdi_readwrite(int cmd, struct request *req);
 
@@ -473,7 +473,7 @@ static void __init ps2esdi_get_device_cfg(void)
 }
 
 /* strategy routine that handles most of the IO requests */
-static void do_ps2esdi_request(request_queue_t * q)
+static void do_ps2esdi_request(struct request_queue * q)
 {
 	struct request *req;
 	/* since, this routine is called with interrupts cleared - they 
diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
index 170fb33dba97..aa8b890c80d7 100644
--- a/drivers/block/ps3disk.c
+++ b/drivers/block/ps3disk.c
@@ -190,7 +190,7 @@ static int ps3disk_submit_flush_request(struct ps3_storage_device *dev,
 }
 
 static void ps3disk_do_request(struct ps3_storage_device *dev,
-			       request_queue_t *q)
+			       struct request_queue *q)
 {
 	struct request *req;
 
@@ -211,7 +211,7 @@ static void ps3disk_do_request(struct ps3_storage_device *dev,
 	}
 }
 
-static void ps3disk_request(request_queue_t *q)
+static void ps3disk_request(struct request_queue *q)
 {
 	struct ps3_storage_device *dev = q->queuedata;
 	struct ps3disk_private *priv = dev->sbd.core.driver_data;
@@ -404,7 +404,7 @@ static int ps3disk_identify(struct ps3_storage_device *dev)
 	return 0;
 }
 
-static void ps3disk_prepare_flush(request_queue_t *q, struct request *req)
+static void ps3disk_prepare_flush(struct request_queue *q, struct request *req)
 {
 	struct ps3_storage_device *dev = q->queuedata;
 
@@ -414,7 +414,7 @@ static void ps3disk_prepare_flush(request_queue_t *q, struct request *req)
 	req->cmd_type = REQ_TYPE_FLUSH;
 }
 
-static int ps3disk_issue_flush(request_queue_t *q, struct gendisk *gendisk,
+static int ps3disk_issue_flush(struct request_queue *q, struct gendisk *gendisk,
 			       sector_t *sector)
 {
 	struct ps3_storage_device *dev = q->queuedata;
diff --git a/drivers/block/rd.c b/drivers/block/rd.c
index a1512da32410..65150b548f3a 100644
--- a/drivers/block/rd.c
+++ b/drivers/block/rd.c
@@ -264,7 +264,7 @@ static int rd_blkdev_pagecache_IO(int rw, struct bio_vec *vec, sector_t sector,
  * 19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Added devfs support
  *
  */
-static int rd_make_request(request_queue_t *q, struct bio *bio)
+static int rd_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
 	struct address_space * mapping = bdev->bd_inode->i_mapping;
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index d50b82381155..4dff49256ac2 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -444,7 +444,7 @@ out:
 	return err;
 }
 
-static void do_vdc_request(request_queue_t *q)
+static void do_vdc_request(struct request_queue *q)
 {
 	while (1) {
 		struct request *req = elv_next_request(q);
diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index 1a65979f1f0f..b4e462f154ea 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -225,7 +225,7 @@ static unsigned short write_postamble[] = {
 static void swim3_select(struct floppy_state *fs, int sel);
 static void swim3_action(struct floppy_state *fs, int action);
 static int swim3_readbit(struct floppy_state *fs, int bit);
-static void do_fd_request(request_queue_t * q);
+static void do_fd_request(struct request_queue * q);
 static void start_request(struct floppy_state *fs);
 static void set_timeout(struct floppy_state *fs, int nticks,
 			void (*proc)(unsigned long));
@@ -290,7 +290,7 @@ static int swim3_readbit(struct floppy_state *fs, int bit)
 	return (stat & DATA) == 0;
 }
 
-static void do_fd_request(request_queue_t * q)
+static void do_fd_request(struct request_queue * q)
 {
 	int i;
 	for(i=0;i<floppy_count;i++)
diff --git a/drivers/block/sx8.c b/drivers/block/sx8.c
index 949ae93499e5..402209fec59a 100644
--- a/drivers/block/sx8.c
+++ b/drivers/block/sx8.c
@@ -278,7 +278,7 @@ struct carm_host {
 	unsigned int			state;
 	u32				fw_ver;
 
-	request_queue_t			*oob_q;
+	struct request_queue		*oob_q;
 	unsigned int			n_oob;
 
 	unsigned int			hw_sg_used;
@@ -287,7 +287,7 @@ struct carm_host {
 
 	unsigned int			wait_q_prod;
 	unsigned int			wait_q_cons;
-	request_queue_t			*wait_q[CARM_MAX_WAIT_Q];
+	struct request_queue		*wait_q[CARM_MAX_WAIT_Q];
 
 	unsigned int			n_msgs;
 	u64				msg_alloc;
@@ -756,7 +756,7 @@ static inline void carm_end_request_queued(struct carm_host *host,
 	assert(rc == 0);
 }
 
-static inline void carm_push_q (struct carm_host *host, request_queue_t *q)
+static inline void carm_push_q (struct carm_host *host, struct request_queue *q)
 {
 	unsigned int idx = host->wait_q_prod % CARM_MAX_WAIT_Q;
 
@@ -768,7 +768,7 @@ static inline void carm_push_q (struct carm_host *host, request_queue_t *q)
 	BUG_ON(host->wait_q_prod == host->wait_q_cons); /* overrun */
 }
 
-static inline request_queue_t *carm_pop_q(struct carm_host *host)
+static inline struct request_queue *carm_pop_q(struct carm_host *host)
 {
 	unsigned int idx;
 
@@ -783,7 +783,7 @@ static inline request_queue_t *carm_pop_q(struct carm_host *host)
 
 static inline void carm_round_robin(struct carm_host *host)
 {
-	request_queue_t *q = carm_pop_q(host);
+	struct request_queue *q = carm_pop_q(host);
 	if (q) {
 		blk_start_queue(q);
 		VPRINTK("STARTED QUEUE %p\n", q);
@@ -802,7 +802,7 @@ static inline void carm_end_rq(struct carm_host *host, struct carm_request *crq,
 	}
 }
 
-static void carm_oob_rq_fn(request_queue_t *q)
+static void carm_oob_rq_fn(struct request_queue *q)
 {
 	struct carm_host *host = q->queuedata;
 	struct carm_request *crq;
@@ -833,7 +833,7 @@ static void carm_oob_rq_fn(request_queue_t *q)
 	}
 }
 
-static void carm_rq_fn(request_queue_t *q)
+static void carm_rq_fn(struct request_queue *q)
 {
 	struct carm_port *port = q->queuedata;
 	struct carm_host *host = port->host;
@@ -1494,7 +1494,7 @@ static int carm_init_disks(struct carm_host *host)
 
 	for (i = 0; i < CARM_MAX_PORTS; i++) {
 		struct gendisk *disk;
-		request_queue_t *q;
+		struct request_queue *q;
 		struct carm_port *port;
 
 		port = &host->port[i];
@@ -1538,7 +1538,7 @@ static void carm_free_disks(struct carm_host *host)
 	for (i = 0; i < CARM_MAX_PORTS; i++) {
 		struct gendisk *disk = host->port[i].disk;
 		if (disk) {
-			request_queue_t *q = disk->queue;
+			struct request_queue *q = disk->queue;
 
 			if (disk->flags & GENHD_FL_UP)
 				del_gendisk(disk);
@@ -1571,7 +1571,7 @@ static int carm_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
 	struct carm_host *host;
 	unsigned int pci_dac;
 	int rc;
-	request_queue_t *q;
+	struct request_queue *q;
 	unsigned int i;
 
 	if (!printed_version++)
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index 8b13d7d2cb63..c57dd2b3a0c8 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -503,7 +503,7 @@ static void ub_cleanup(struct ub_dev *sc)
 {
 	struct list_head *p;
 	struct ub_lun *lun;
-	request_queue_t *q;
+	struct request_queue *q;
 
 	while (!list_empty(&sc->luns)) {
 		p = sc->luns.next;
@@ -619,7 +619,7 @@ static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
  * The request function is our main entry point
  */
 
-static void ub_request_fn(request_queue_t *q)
+static void ub_request_fn(struct request_queue *q)
 {
 	struct ub_lun *lun = q->queuedata;
 	struct request *rq;
@@ -2273,7 +2273,7 @@ err_core:
 static int ub_probe_lun(struct ub_dev *sc, int lnum)
 {
 	struct ub_lun *lun;
-	request_queue_t *q;
+	struct request_queue *q;
 	struct gendisk *disk;
 	int rc;
 
diff --git a/drivers/block/umem.c b/drivers/block/umem.c
index dec74bd23496..6b7c02d6360d 100644
--- a/drivers/block/umem.c
+++ b/drivers/block/umem.c
@@ -114,7 +114,7 @@ struct cardinfo {
 				    */
 	struct bio	*bio, *currentbio, **biotail;
 
-	request_queue_t *queue;
+	struct request_queue *queue;
 
 	struct mm_page {
 		dma_addr_t		page_dma;
@@ -357,7 +357,7 @@ static inline void reset_page(struct mm_page *page)
 	page->biotail = & page->bio;
 }
 
-static void mm_unplug_device(request_queue_t *q)
+static void mm_unplug_device(struct request_queue *q)
 {
 	struct cardinfo *card = q->queuedata;
 	unsigned long flags;
@@ -541,7 +541,7 @@ static void process_page(unsigned long data)
 --                              mm_make_request
 -----------------------------------------------------------------------------------
 */
-static int mm_make_request(request_queue_t *q, struct bio *bio)
+static int mm_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct cardinfo *card = q->queuedata;
 	pr_debug("mm_make_request %llu %u\n",
diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c
index dae39911a11d..85916e2665d4 100644
--- a/drivers/block/viodasd.c
+++ b/drivers/block/viodasd.c
@@ -400,7 +400,7 @@ error_ret:
 /*
  * This is the external request processing routine
  */
-static void do_viodasd_request(request_queue_t *q)
+static void do_viodasd_request(struct request_queue *q)
 {
 	struct request *req;
 
diff --git a/drivers/block/xd.c b/drivers/block/xd.c
index 0d97b7eb818a..624d30f7da3f 100644
--- a/drivers/block/xd.c
+++ b/drivers/block/xd.c
@@ -298,7 +298,7 @@ static u_char __init xd_detect (u_char *controller, unsigned int *address)
 }
 
 /* do_xd_request: handle an incoming request */
-static void do_xd_request (request_queue_t * q)
+static void do_xd_request (struct request_queue * q)
 {
 	struct request *req;
 
diff --git a/drivers/block/xd.h b/drivers/block/xd.h
index 82e090fea957..cffd44a20383 100644
--- a/drivers/block/xd.h
+++ b/drivers/block/xd.h
@@ -104,7 +104,7 @@ static int xd_manual_geo_init (char *command);
 static u_char xd_detect (u_char *controller, unsigned int *address);
 static u_char xd_initdrives (void (*init_drive)(u_char drive));
 
-static void do_xd_request (request_queue_t * q);
+static void do_xd_request (struct request_queue * q);
 static int xd_ioctl (struct inode *inode,struct file *file,unsigned int cmd,unsigned long arg);
 static int xd_readwrite (u_char operation,XD_INFO *disk,char *buffer,u_int block,u_int count);
 static void xd_recalibrate (u_char drive);
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 6746c29181f8..964e51634f2d 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -241,7 +241,7 @@ static inline void flush_requests(struct blkfront_info *info)
  * do_blkif_request
  *  read a block; request is in a request queue
  */
-static void do_blkif_request(request_queue_t *rq)
+static void do_blkif_request(struct request_queue *rq)
 {
 	struct blkfront_info *info = NULL;
 	struct request *req;
@@ -287,7 +287,7 @@ wait:
 
 static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
 {
-	request_queue_t *rq;
+	struct request_queue *rq;
 
 	rq = blk_init_queue(do_blkif_request, &blkif_io_lock);
 	if (rq == NULL)
diff --git a/drivers/block/xsysace.c b/drivers/block/xsysace.c
index 732ec63b6e9c..cb27e8863d7c 100644
--- a/drivers/block/xsysace.c
+++ b/drivers/block/xsysace.c
@@ -458,7 +458,7 @@ static inline void ace_fsm_yieldirq(struct ace_device *ace)
 }
 
 /* Get the next read/write request; ending requests that we don't handle */
-struct request *ace_get_next_request(request_queue_t * q)
+struct request *ace_get_next_request(struct request_queue * q)
 {
 	struct request *req;
 
@@ -825,7 +825,7 @@ static irqreturn_t ace_interrupt(int irq, void *dev_id)
 /* ---------------------------------------------------------------------
  * Block ops
  */
-static void ace_request(request_queue_t * q)
+static void ace_request(struct request_queue * q)
 {
 	struct request *req;
 	struct ace_device *ace;
diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index e40fa98842e5..2d5853cbd4b0 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -67,7 +67,7 @@ static DEFINE_SPINLOCK(z2ram_lock);
 static struct block_device_operations z2_fops;
 static struct gendisk *z2ram_gendisk;
 
-static void do_z2_request(request_queue_t *q)
+static void do_z2_request(struct request_queue *q)
 {
 	struct request *req;
 	while ((req = elv_next_request(q)) != NULL) {