|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] blkfront cleanup and retab.
# HG changeset patch
# User kaf24@xxxxxxxxxxxxxxxxxxxx
# Node ID fb2fae2cc003e24bbfccedb8f8419ecc759e1a3b
# Parent 15d378281a0b03c0c04b90890c2d07e83e4fecf9
blkfront cleanup and retab.
Signed-off-by: Keir Fraser <keir@xxxxxxxxxxxxx>
diff -r 15d378281a0b -r fb2fae2cc003
linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c
--- a/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c Sat Aug 27
11:49:35 2005
+++ b/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c Sun Aug 28
14:21:08 2005
@@ -32,23 +32,15 @@
*/
#if 1
-#define ASSERT(_p) \
- if ( !(_p) ) { printk("Assertion '%s' failed, line %d, file %s", #_p , \
- __LINE__, __FILE__); *(int*)0=0; }
+#define ASSERT(p) \
+ if (!(p)) { printk("Assertion '%s' failed, line %d, file %s", #p , \
+ __LINE__, __FILE__); *(int*)0=0; }
#else
#define ASSERT(_p)
#endif
#include <linux/version.h>
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
#include "block.h"
-#else
-#include "common.h"
-#include <linux/blk.h>
-#include <linux/tqueue.h>
-#endif
-
#include <linux/cdrom.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
@@ -58,11 +50,6 @@
#include <asm-xen/xen-public/grant_table.h>
#include <asm-xen/gnttab.h>
-typedef unsigned char byte; /* from linux/ide.h */
-
-/* Control whether runtime update of vbds is enabled. */
-#define ENABLE_VBD_UPDATE 1
-
#define BLKIF_STATE_DISCONNECTED 0
#define BLKIF_STATE_CONNECTED 1
@@ -75,9 +62,9 @@
#define GRANTREF_INVALID (1<<15)
static struct blk_shadow {
- blkif_request_t req;
- unsigned long request;
- unsigned long frame[BLKIF_MAX_SEGMENTS_PER_REQUEST];
+ blkif_request_t req;
+ unsigned long request;
+ unsigned long frame[BLKIF_MAX_SEGMENTS_PER_REQUEST];
} blk_shadow[BLK_RING_SIZE];
unsigned long blk_shadow_free;
@@ -85,63 +72,41 @@
static void kick_pending_request_queues(struct blkfront_info *info);
-static int __init xlblk_init(void);
-
static void blkif_completion(struct blk_shadow *s);
static inline int GET_ID_FROM_FREELIST(void)
{
- unsigned long free = blk_shadow_free;
- BUG_ON(free > BLK_RING_SIZE);
- blk_shadow_free = blk_shadow[free].req.id;
- blk_shadow[free].req.id = 0x0fffffee; /* debug */
- return free;
+ unsigned long free = blk_shadow_free;
+ BUG_ON(free > BLK_RING_SIZE);
+ blk_shadow_free = blk_shadow[free].req.id;
+ blk_shadow[free].req.id = 0x0fffffee; /* debug */
+ return free;
}
static inline void ADD_ID_TO_FREELIST(unsigned long id)
{
- blk_shadow[id].req.id = blk_shadow_free;
- blk_shadow[id].request = 0;
- blk_shadow_free = id;
-}
-
-
-/************************ COMMON CODE (inlined) ************************/
-
-/* Kernel-specific definitions used in the common code */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
-#define DISABLE_SCATTERGATHER()
-#else
-static int sg_operation = -1;
-#define DISABLE_SCATTERGATHER() (sg_operation = -1)
-#endif
+ blk_shadow[id].req.id = blk_shadow_free;
+ blk_shadow[id].request = 0;
+ blk_shadow_free = id;
+}
static inline void pickle_request(struct blk_shadow *s, blkif_request_t *r)
{
- s->req = *r;
+ s->req = *r;
}
static inline void unpickle_request(blkif_request_t *r, struct blk_shadow *s)
{
- *r = s->req;
-}
-
+ *r = s->req;
+}
static inline void flush_requests(struct blkfront_info *info)
{
- DISABLE_SCATTERGATHER();
- RING_PUSH_REQUESTS(&info->ring);
- notify_via_evtchn(info->evtchn);
-}
-
-
-/************************** KERNEL VERSION 2.6 **************************/
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
-
-module_init(xlblk_init);
+ RING_PUSH_REQUESTS(&info->ring);
+ notify_via_evtchn(info->evtchn);
+}
static void kick_pending_request_queues(struct blkfront_info *info)
{
@@ -169,50 +134,44 @@
int blkif_open(struct inode *inode, struct file *filep)
{
- // struct gendisk *gd = inode->i_bdev->bd_disk;
- // struct xlbd_disk_info *di = (struct xlbd_disk_info
*)gd->private_data;
-
- /* Update of usage count is protected by per-device semaphore. */
- // di->mi->usage++;
-
return 0;
}
int blkif_release(struct inode *inode, struct file *filep)
{
- /* FIXME: This is where we can actually free up majors, etc. --RR */
- return 0;
+ return 0;
}
int blkif_ioctl(struct inode *inode, struct file *filep,
unsigned command, unsigned long argument)
{
- int i;
-
- DPRINTK_IOCTL("command: 0x%x, argument: 0x%lx, dev: 0x%04x\n",
- command, (long)argument, inode->i_rdev);
-
- switch ( command )
- {
- case HDIO_GETGEO:
- /* return ENOSYS to use defaults */
- return -ENOSYS;
-
- case CDROMMULTISESSION:
- DPRINTK("FIXME: support multisession CDs later\n");
- for ( i = 0; i < sizeof(struct cdrom_multisession); i++ )
- if ( put_user(0, (byte *)(argument + i)) ) return -EFAULT;
- return 0;
-
- default:
- /*printk(KERN_ALERT "ioctl %08x not supported by Xen blkdev\n",
- command);*/
- return -EINVAL; /* same return as native Linux */
- }
-
- return 0;
+ int i;
+
+ DPRINTK_IOCTL("command: 0x%x, argument: 0x%lx, dev: 0x%04x\n",
+ command, (long)argument, inode->i_rdev);
+
+ switch ( command )
+ {
+ case HDIO_GETGEO:
+ /* return ENOSYS to use defaults */
+ return -ENOSYS;
+
+ case CDROMMULTISESSION:
+ DPRINTK("FIXME: support multisession CDs later\n");
+ for (i = 0; i < sizeof(struct cdrom_multisession); i++)
+ if (put_user(0, (char *)(argument + i)))
+ return -EFAULT;
+ return 0;
+
+ default:
+ /*printk(KERN_ALERT "ioctl %08x not supported by Xen blkdev\n",
+ command);*/
+ return -EINVAL; /* same return as native Linux */
+ }
+
+ return 0;
}
@@ -228,76 +187,77 @@
*/
static int blkif_queue_request(struct request *req)
{
- struct blkfront_info *info = req->rq_disk->private_data;
- unsigned long buffer_ma;
- blkif_request_t *ring_req;
- struct bio *bio;
- struct bio_vec *bvec;
- int idx;
- unsigned long id;
- unsigned int fsect, lsect;
- int ref;
- grant_ref_t gref_head;
-
- if (unlikely(info->connected != BLKIF_STATE_CONNECTED))
- return 1;
-
- if (gnttab_alloc_grant_references(BLKIF_MAX_SEGMENTS_PER_REQUEST,
- &gref_head) < 0) {
- gnttab_request_free_callback(&info->callback,
- blkif_restart_queue_callback, info,
- BLKIF_MAX_SEGMENTS_PER_REQUEST);
- return 1;
- }
-
- /* Fill out a communications ring structure. */
- ring_req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt);
- id = GET_ID_FROM_FREELIST();
- blk_shadow[id].request = (unsigned long)req;
-
- ring_req->id = id;
- ring_req->operation = rq_data_dir(req) ? BLKIF_OP_WRITE : BLKIF_OP_READ;
- ring_req->sector_number = (blkif_sector_t)req->sector;
- ring_req->handle = info->handle;
-
- ring_req->nr_segments = 0;
- rq_for_each_bio(bio, req)
- {
- bio_for_each_segment(bvec, bio, idx)
- {
- if ( ring_req->nr_segments == BLKIF_MAX_SEGMENTS_PER_REQUEST )
- BUG();
- buffer_ma = page_to_phys(bvec->bv_page);
- fsect = bvec->bv_offset >> 9;
- lsect = fsect + (bvec->bv_len >> 9) - 1;
- /* install a grant reference. */
- ref = gnttab_claim_grant_reference(&gref_head);
- ASSERT( ref != -ENOSPC );
-
- gnttab_grant_foreign_access_ref(
- ref,
- info->backend_id,
- buffer_ma >> PAGE_SHIFT,
- rq_data_dir(req) );
-
- blk_shadow[id].frame[ring_req->nr_segments] =
- buffer_ma >> PAGE_SHIFT;
-
- ring_req->frame_and_sects[ring_req->nr_segments] =
- blkif_fas_from_gref(ref, fsect, lsect);
-
- ring_req->nr_segments++;
- }
- }
-
- info->ring.req_prod_pvt++;
-
- /* Keep a private copy so we can reissue requests when recovering. */
- pickle_request(&blk_shadow[id], ring_req);
-
- gnttab_free_grant_references(gref_head);
-
- return 0;
+ struct blkfront_info *info = req->rq_disk->private_data;
+ unsigned long buffer_ma;
+ blkif_request_t *ring_req;
+ struct bio *bio;
+ struct bio_vec *bvec;
+ int idx;
+ unsigned long id;
+ unsigned int fsect, lsect;
+ int ref;
+ grant_ref_t gref_head;
+
+ if (unlikely(info->connected != BLKIF_STATE_CONNECTED))
+ return 1;
+
+ if (gnttab_alloc_grant_references(
+ BLKIF_MAX_SEGMENTS_PER_REQUEST, &gref_head) < 0) {
+ gnttab_request_free_callback(
+ &info->callback,
+ blkif_restart_queue_callback,
+ info,
+ BLKIF_MAX_SEGMENTS_PER_REQUEST);
+ return 1;
+ }
+
+ /* Fill out a communications ring structure. */
+ ring_req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt);
+ id = GET_ID_FROM_FREELIST();
+ blk_shadow[id].request = (unsigned long)req;
+
+ ring_req->id = id;
+ ring_req->operation = rq_data_dir(req) ?
+ BLKIF_OP_WRITE : BLKIF_OP_READ;
+ ring_req->sector_number = (blkif_sector_t)req->sector;
+ ring_req->handle = info->handle;
+
+ ring_req->nr_segments = 0;
+ rq_for_each_bio (bio, req) {
+ bio_for_each_segment (bvec, bio, idx) {
+ BUG_ON(ring_req->nr_segments
+ == BLKIF_MAX_SEGMENTS_PER_REQUEST);
+ buffer_ma = page_to_phys(bvec->bv_page);
+ fsect = bvec->bv_offset >> 9;
+ lsect = fsect + (bvec->bv_len >> 9) - 1;
+ /* install a grant reference. */
+ ref = gnttab_claim_grant_reference(&gref_head);
+ ASSERT(ref != -ENOSPC);
+
+ gnttab_grant_foreign_access_ref(
+ ref,
+ info->backend_id,
+ buffer_ma >> PAGE_SHIFT,
+ rq_data_dir(req) );
+
+ blk_shadow[id].frame[ring_req->nr_segments] =
+ buffer_ma >> PAGE_SHIFT;
+
+ ring_req->frame_and_sects[ring_req->nr_segments] =
+ blkif_fas_from_gref(ref, fsect, lsect);
+
+ ring_req->nr_segments++;
+ }
+ }
+
+ info->ring.req_prod_pvt++;
+
+ /* Keep a private copy so we can reissue requests when recovering. */
+ pickle_request(&blk_shadow[id], ring_req);
+
+ gnttab_free_grant_references(gref_head);
+
+ return 0;
}
/*
@@ -306,756 +266,197 @@
*/
void do_blkif_request(request_queue_t *rq)
{
- struct blkfront_info *info = NULL;
- struct request *req;
- int queued;
-
- DPRINTK("Entered do_blkif_request\n");
-
- queued = 0;
-
- while ( (req = elv_next_request(rq)) != NULL )
- {
- info = req->rq_disk->private_data;
-
- if ( !blk_fs_request(req) )
- {
- end_request(req, 0);
- continue;
- }
-
- if (RING_FULL(&info->ring))
- goto wait;
-
- DPRINTK("do_blk_req %p: cmd %p, sec %lx, (%u/%li) buffer:%p [%s]\n",
- req, req->cmd, req->sector, req->current_nr_sectors,
- req->nr_sectors, req->buffer,
- rq_data_dir(req) ? "write" : "read");
-
- blkdev_dequeue_request(req);
- if (blkif_queue_request(req)) {
- blk_requeue_request(rq, req);
- wait:
- /* Avoid pointless unplugs. */
- blk_stop_queue(rq);
- break;
- }
-
- queued++;
- }
-
- if ( queued != 0 )
- flush_requests(info);
+ struct blkfront_info *info = NULL;
+ struct request *req;
+ int queued;
+
+ DPRINTK("Entered do_blkif_request\n");
+
+ queued = 0;
+
+ while ((req = elv_next_request(rq)) != NULL) {
+ info = req->rq_disk->private_data;
+
+ if (!blk_fs_request(req)) {
+ end_request(req, 0);
+ continue;
+ }
+
+ if (RING_FULL(&info->ring))
+ goto wait;
+
+ DPRINTK("do_blk_req %p: cmd %p, sec %lx, "
+ "(%u/%li) buffer:%p [%s]\n",
+ req, req->cmd, req->sector, req->current_nr_sectors,
+ req->nr_sectors, req->buffer,
+ rq_data_dir(req) ? "write" : "read");
+
+ blkdev_dequeue_request(req);
+ if (blkif_queue_request(req)) {
+ blk_requeue_request(rq, req);
+ wait:
+ /* Avoid pointless unplugs. */
+ blk_stop_queue(rq);
+ break;
+ }
+
+ queued++;
+ }
+
+ if (queued != 0)
+ flush_requests(info);
}
static irqreturn_t blkif_int(int irq, void *dev_id, struct pt_regs *ptregs)
{
- struct request *req;
- blkif_response_t *bret;
- RING_IDX i, rp;
- unsigned long flags;
- struct blkfront_info *info = (struct blkfront_info *)dev_id;
-
- spin_lock_irqsave(&blkif_io_lock, flags);
-
- if (unlikely(info->connected != BLKIF_STATE_CONNECTED || recovery)) {
- spin_unlock_irqrestore(&blkif_io_lock, flags);
- return IRQ_HANDLED;
- }
-
- rp = info->ring.sring->rsp_prod;
- rmb(); /* Ensure we see queued responses up to 'rp'. */
-
- for ( i = info->ring.rsp_cons; i != rp; i++ )
- {
- unsigned long id;
-
- bret = RING_GET_RESPONSE(&info->ring, i);
- id = bret->id;
- req = (struct request *)blk_shadow[id].request;
-
- blkif_completion(&blk_shadow[id]);
-
- ADD_ID_TO_FREELIST(id);
-
- switch ( bret->operation )
- {
- case BLKIF_OP_READ:
- case BLKIF_OP_WRITE:
- if ( unlikely(bret->status != BLKIF_RSP_OKAY) )
- DPRINTK("Bad return from blkdev data request: %x\n",
- bret->status);
-
- if ( unlikely(end_that_request_first
- (req,
- (bret->status == BLKIF_RSP_OKAY),
- req->hard_nr_sectors)) )
- BUG();
- end_that_request_last(req);
-
- break;
- default:
- BUG();
- }
- }
-
- info->ring.rsp_cons = i;
-
- kick_pending_request_queues(info);
-
- spin_unlock_irqrestore(&blkif_io_lock, flags);
-
- return IRQ_HANDLED;
-}
-
-#else
-/************************** KERNEL VERSION 2.4 **************************/
-
-static kdev_t sg_dev;
-static unsigned long sg_next_sect;
-
-/*
- * Request queues with outstanding work, but ring is currently full.
- * We need no special lock here, as we always access this with the
- * blkif_io_lock held. We only need a small maximum list.
- */
-#define MAX_PENDING 8
-static request_queue_t *pending_queues[MAX_PENDING];
-static int nr_pending;
-
-
-#define blkif_io_lock io_request_lock
-
-/*============================================================================*/
-static void kick_pending_request_queues(void)
-{
- /* We kick pending request queues if the ring is reasonably empty. */
- if ( (nr_pending != 0) &&
- (RING_PENDING_REQUESTS(&info->ring) < (BLK_RING_SIZE >> 1)) )
- {
- /* Attempt to drain the queue, but bail if the ring becomes full. */
- while ( (nr_pending != 0) && !RING_FULL(&info->ring) )
- do_blkif_request(pending_queues[--nr_pending]);
- }
-}
-
-int blkif_open(struct inode *inode, struct file *filep)
-{
- short xldev = inode->i_rdev;
- struct gendisk *gd = get_gendisk(xldev);
- xl_disk_t *disk = xldev_to_xldisk(inode->i_rdev);
- short minor = MINOR(xldev);
-
- if ( gd->part[minor].nr_sects == 0 )
- {
- /*
- * Device either doesn't exist, or has zero capacity; we use a few
- * cheesy heuristics to return the relevant error code
- */
- if ( (gd->sizes[minor >> gd->minor_shift] != 0) ||
- ((minor & (gd->max_p - 1)) != 0) )
- {
- /*
- * We have a real device, but no such partition, or we just have a
- * partition number so guess this is the problem.
- */
- return -ENXIO; /* no such device or address */
- }
- else if ( gd->flags[minor >> gd->minor_shift] & GENHD_FL_REMOVABLE )
- {
- /* This is a removable device => assume that media is missing. */
- return -ENOMEDIUM; /* media not present (this is a guess) */
- }
- else
- {
- /* Just go for the general 'no such device' error. */
- return -ENODEV; /* no such device */
- }
- }
-
- /* Update of usage count is protected by per-device semaphore. */
- disk->usage++;
-
- return 0;
-}
-
-
-int blkif_release(struct inode *inode, struct file *filep)
-{
- xl_disk_t *disk = xldev_to_xldisk(inode->i_rdev);
-
- /*
- * When usage drops to zero it may allow more VBD updates to occur.
- * Update of usage count is protected by a per-device semaphore.
- */
- if ( --disk->usage == 0 ) {
- vbd_update();
- }
-
- return 0;
-}
-
-
-int blkif_ioctl(struct inode *inode, struct file *filep,
- unsigned command, unsigned long argument)
-{
- kdev_t dev = inode->i_rdev;
- struct hd_geometry *geo = (struct hd_geometry *)argument;
- struct gendisk *gd;
- struct hd_struct *part;
- int i;
- unsigned short cylinders;
- byte heads, sectors;
-
- /* NB. No need to check permissions. That is done for us. */
-
- DPRINTK_IOCTL("command: 0x%x, argument: 0x%lx, dev: 0x%04x\n",
- command, (long) argument, dev);
-
- gd = get_gendisk(dev);
- part = &gd->part[MINOR(dev)];
-
- switch ( command )
- {
- case BLKGETSIZE:
- DPRINTK_IOCTL(" BLKGETSIZE: %x %lx\n", BLKGETSIZE, part->nr_sects);
- return put_user(part->nr_sects, (unsigned long *) argument);
-
- case BLKGETSIZE64:
- DPRINTK_IOCTL(" BLKGETSIZE64: %x %llx\n", BLKGETSIZE64,
- (u64)part->nr_sects * 512);
- return put_user((u64)part->nr_sects * 512, (u64 *) argument);
-
- case BLKRRPART: /* re-read partition table */
- DPRINTK_IOCTL(" BLKRRPART: %x\n", BLKRRPART);
- return blkif_revalidate(dev);
-
- case BLKSSZGET:
- return hardsect_size[MAJOR(dev)][MINOR(dev)];
-
- case BLKBSZGET: /* get block size */
- DPRINTK_IOCTL(" BLKBSZGET: %x\n", BLKBSZGET);
- break;
-
- case BLKBSZSET: /* set block size */
- DPRINTK_IOCTL(" BLKBSZSET: %x\n", BLKBSZSET);
- break;
-
- case BLKRASET: /* set read-ahead */
- DPRINTK_IOCTL(" BLKRASET: %x\n", BLKRASET);
- break;
-
- case BLKRAGET: /* get read-ahead */
- DPRINTK_IOCTL(" BLKRAFET: %x\n", BLKRAGET);
- break;
-
- case HDIO_GETGEO:
- DPRINTK_IOCTL(" HDIO_GETGEO: %x\n", HDIO_GETGEO);
- if (!argument) return -EINVAL;
-
- /* We don't have real geometry info, but let's at least return
- values consistent with the size of the device */
-
- heads = 0xff;
- sectors = 0x3f;
- cylinders = part->nr_sects / (heads * sectors);
-
- if (put_user(0x00, (unsigned long *) &geo->start)) return -EFAULT;
- if (put_user(heads, (byte *)&geo->heads)) return -EFAULT;
- if (put_user(sectors, (byte *)&geo->sectors)) return -EFAULT;
- if (put_user(cylinders, (unsigned short *)&geo->cylinders)) return
-EFAULT;
-
- return 0;
-
- case HDIO_GETGEO_BIG:
- DPRINTK_IOCTL(" HDIO_GETGEO_BIG: %x\n", HDIO_GETGEO_BIG);
- if (!argument) return -EINVAL;
-
- /* We don't have real geometry info, but let's at least return
- values consistent with the size of the device */
-
- heads = 0xff;
- sectors = 0x3f;
- cylinders = part->nr_sects / (heads * sectors);
-
- if (put_user(0x00, (unsigned long *) &geo->start)) return -EFAULT;
- if (put_user(heads, (byte *)&geo->heads)) return -EFAULT;
- if (put_user(sectors, (byte *)&geo->sectors)) return -EFAULT;
- if (put_user(cylinders, (unsigned int *) &geo->cylinders)) return
-EFAULT;
-
- return 0;
-
- case CDROMMULTISESSION:
- DPRINTK("FIXME: support multisession CDs later\n");
- for ( i = 0; i < sizeof(struct cdrom_multisession); i++ )
- if ( put_user(0, (byte *)(argument + i)) ) return -EFAULT;
- return 0;
-
- case SCSI_IOCTL_GET_BUS_NUMBER:
- DPRINTK("FIXME: SCSI_IOCTL_GET_BUS_NUMBER ioctl in XL blkif");
- return -ENOSYS;
-
- default:
- WPRINTK("ioctl %08x not supported by XL blkif\n", command);
- return -ENOSYS;
- }
-
- return 0;
-}
-
-
-
-/* check media change: should probably do something here in some cases :-) */
-int blkif_check(kdev_t dev)
-{
- DPRINTK("blkif_check\n");
- return 0;
-}
-
-int blkif_revalidate(kdev_t dev)
-{
- struct block_device *bd;
- struct gendisk *gd;
- xl_disk_t *disk;
- unsigned long capacity;
- int i, rc = 0;
-
- if ( (bd = bdget(dev)) == NULL )
- return -EINVAL;
-
- /*
- * Update of partition info, and check of usage count, is protected
- * by the per-block-device semaphore.
- */
- down(&bd->bd_sem);
-
- if ( ((gd = get_gendisk(dev)) == NULL) ||
- ((disk = xldev_to_xldisk(dev)) == NULL) ||
- ((capacity = gd->part[MINOR(dev)].nr_sects) == 0) )
- {
- rc = -EINVAL;
- goto out;
- }
-
- if ( disk->usage > 1 )
- {
- rc = -EBUSY;
- goto out;
- }
-
- /* Only reread partition table if VBDs aren't mapped to partitions. */
- if ( !(gd->flags[MINOR(dev) >> gd->minor_shift] & GENHD_FL_VIRT_PARTNS) )
- {
- for ( i = gd->max_p - 1; i >= 0; i-- )
- {
- invalidate_device(dev+i, 1);
- gd->part[MINOR(dev+i)].start_sect = 0;
- gd->part[MINOR(dev+i)].nr_sects = 0;
- gd->sizes[MINOR(dev+i)] = 0;
- }
-
- grok_partitions(gd, MINOR(dev)>>gd->minor_shift, gd->max_p, capacity);
- }
-
- out:
- up(&bd->bd_sem);
- bdput(bd);
- return rc;
-}
-
-
-/*
- * blkif_queue_request
- *
- * request block io
- *
- * id: for guest use only.
- * operation: BLKIF_OP_{READ,WRITE,PROBE}
- * buffer: buffer to read/write into. this should be a
- * virtual address in the guest os.
- */
-static int blkif_queue_request(unsigned long id,
- int operation,
- char * buffer,
- unsigned long sector_number,
- unsigned short nr_sectors,
- kdev_t device,
- blkif_vdev_t handle)
-{
- unsigned long buffer_ma = virt_to_bus(buffer);
- unsigned long xid;
- struct gendisk *gd;
- blkif_request_t *req;
- struct buffer_head *bh;
- unsigned int fsect, lsect;
- int ref;
-
- fsect = (buffer_ma & ~PAGE_MASK) >> 9;
- lsect = fsect + nr_sectors - 1;
-
- /* Buffer must be sector-aligned. Extent mustn't cross a page boundary. */
- if ( unlikely((buffer_ma & ((1<<9)-1)) != 0) )
- BUG();
- if ( lsect > ((PAGE_SIZE/512)-1) )
- BUG();
-
- buffer_ma &= PAGE_MASK;
-
- if (unlikely(info->connected != BLKIF_STATE_CONNECTED))
- return 1;
-
- switch ( operation )
- {
-
- case BLKIF_OP_READ:
- case BLKIF_OP_WRITE:
- gd = get_gendisk(device);
-
- /*
- * Update the sector_number we'll pass down as appropriate; note that
- * we could sanity check that resulting sector will be in this
- * partition, but this will happen in driver backend anyhow.
- */
- sector_number += gd->part[MINOR(device)].start_sect;
-
- /*
- * If this unit doesn't consist of virtual partitions then we clear
- * the partn bits from the device number.
- */
- if ( !(gd->flags[MINOR(device)>>gd->minor_shift] &
- GENHD_FL_VIRT_PARTNS) )
- device &= ~(gd->max_p - 1);
-
- if ( (sg_operation == operation) &&
- (sg_dev == device) &&
- (sg_next_sect == sector_number) )
- {
- req = RING_GET_REQUEST(&info->ring,
- info->ring.req_prod_pvt - 1);
- bh = (struct buffer_head *)id;
-
- bh->b_reqnext = (struct buffer_head *)blk_shadow[req->id].request;
- blk_shadow[req->id].request = (unsigned long)id;
-
- /* install a grant reference. */
- ref = gnttab_claim_grant_reference(&gref_head);
- ASSERT( ref != -ENOSPC );
-
- gnttab_grant_foreign_access_ref(
- ref,
- info->backend_id,
- buffer_ma >> PAGE_SHIFT,
- ( operation == BLKIF_OP_WRITE ? 1 : 0 ) );
-
- blk_shadow[req->id].frame[req->nr_segments] =
- buffer_ma >> PAGE_SHIFT;
-
- req->frame_and_sects[req->nr_segments] =
- blkif_fas_from_gref(ref, fsect, lsect);
- if ( ++req->nr_segments < BLKIF_MAX_SEGMENTS_PER_REQUEST )
- sg_next_sect += nr_sectors;
- else
- DISABLE_SCATTERGATHER();
-
- /* Update the copy of the request in the recovery ring. */
- pickle_request(&blk_shadow[req->id], req );
-
- return 0;
- }
- else if ( RING_FULL(&info->ring) )
- {
- return 1;
- }
- else
- {
- sg_operation = operation;
- sg_dev = device;
- sg_next_sect = sector_number + nr_sectors;
- }
- break;
-
- default:
- panic("unknown op %d\n", operation);
- }
-
- /* Fill out a communications ring structure. */
- req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt);
-
- xid = GET_ID_FROM_FREELIST();
- blk_shadow[xid].request = (unsigned long)id;
-
- req->id = xid;
- req->operation = operation;
- req->sector_number = (blkif_sector_t)sector_number;
- req->handle = handle;
- req->nr_segments = 1;
- /* install a grant reference. */
- ref = gnttab_claim_grant_reference(&gref_head);
- ASSERT( ref != -ENOSPC );
-
- gnttab_grant_foreign_access_ref(
- ref,
- info->backend_id,
- buffer_ma >> PAGE_SHIFT,
- ( operation == BLKIF_OP_WRITE ? 1 : 0 ) );
-
- blk_shadow[xid].frame[0] = buffer_ma >> PAGE_SHIFT;
-
- req->frame_and_sects[0] = blkif_fas_from_gref(ref, fsect, lsect);
-
- /* Keep a private copy so we can reissue requests when recovering. */
- pickle_request(&blk_shadow[xid], req);
-
- info->ring.req_prod_pvt++;
-
- return 0;
-}
-
-
-/*
- * do_blkif_request
- * read a block; request is in a request queue
- */
-void do_blkif_request(request_queue_t *rq)
-{
- struct request *req;
- struct buffer_head *bh, *next_bh;
- int rw, nsect, full, queued = 0;
-
- DPRINTK("Entered do_blkif_request\n");
-
- while ( !rq->plugged && !list_empty(&rq->queue_head))
- {
- if ( (req = blkdev_entry_next_request(&rq->queue_head)) == NULL )
- goto out;
-
- DPRINTK("do_blkif_request %p: cmd %i, sec %lx, (%li/%li) bh:%p\n",
- req, req->cmd, req->sector,
- req->current_nr_sectors, req->nr_sectors, req->bh);
-
- rw = req->cmd;
- if ( rw == READA )
- rw = READ;
- if ( unlikely((rw != READ) && (rw != WRITE)) )
- panic("XenoLinux Virtual Block Device: bad cmd: %d\n", rw);
-
- req->errors = 0;
-
- bh = req->bh;
- while ( bh != NULL )
- {
- next_bh = bh->b_reqnext;
- bh->b_reqnext = NULL;
-
- full = blkif_queue_request(
- (unsigned long)bh,
- (rw == READ) ? BLKIF_OP_READ : BLKIF_OP_WRITE,
- bh->b_data, bh->b_rsector, bh->b_size>>9, bh->b_rdev);
-
- if ( full )
- {
- bh->b_reqnext = next_bh;
- pending_queues[nr_pending++] = rq;
- if ( unlikely(nr_pending >= MAX_PENDING) )
- BUG();
- goto out;
- }
-
- queued++;
-
- /* Dequeue the buffer head from the request. */
- nsect = bh->b_size >> 9;
- bh = req->bh = next_bh;
-
- if ( bh != NULL )
- {
- /* There's another buffer head to do. Update the request. */
- req->hard_sector += nsect;
- req->hard_nr_sectors -= nsect;
- req->sector = req->hard_sector;
- req->nr_sectors = req->hard_nr_sectors;
- req->current_nr_sectors = bh->b_size >> 9;
- req->buffer = bh->b_data;
- }
- else
- {
- /* That was the last buffer head. Finalise the request. */
- if ( unlikely(end_that_request_first(req, 1, "XenBlk")) )
- BUG();
- blkdev_dequeue_request(req);
- end_that_request_last(req);
- }
- }
- }
-
- out:
- if ( queued != 0 )
- flush_requests();
-}
-
-
-static void blkif_int(int irq, void *dev_id, struct pt_regs *ptregs)
-{
- RING_IDX i, rp;
- unsigned long flags;
- struct buffer_head *bh, *next_bh;
-
- spin_lock_irqsave(&io_request_lock, flags);
-
- if ( unlikely(info->connected != BLKIF_STATE_CONNECTED || recovery) )
- {
- spin_unlock_irqrestore(&io_request_lock, flags);
- return;
- }
-
- rp = info->ring.sring->rsp_prod;
- rmb(); /* Ensure we see queued responses up to 'rp'. */
-
- for ( i = info->ring.rsp_cons; i != rp; i++ )
- {
- unsigned long id;
- blkif_response_t *bret;
-
- bret = RING_GET_RESPONSE(&info->ring, i);
- id = bret->id;
- bh = (struct buffer_head *)blk_shadow[id].request;
-
- blkif_completion(&blk_shadow[id]);
-
- ADD_ID_TO_FREELIST(id);
-
- switch ( bret->operation )
- {
- case BLKIF_OP_READ:
- case BLKIF_OP_WRITE:
- if ( unlikely(bret->status != BLKIF_RSP_OKAY) )
- DPRINTK("Bad return from blkdev data request: %lx\n",
- bret->status);
- for ( ; bh != NULL; bh = next_bh )
- {
- next_bh = bh->b_reqnext;
- bh->b_reqnext = NULL;
- bh->b_end_io(bh, bret->status == BLKIF_RSP_OKAY);
- }
-
- break;
- case BLKIF_OP_PROBE:
- memcpy(&blkif_control_rsp, bret, sizeof(*bret));
- blkif_control_rsp_valid = 1;
- break;
- default:
- BUG();
- }
-
- }
- info->ring.rsp_cons = i;
-
- kick_pending_request_queues();
-
- spin_unlock_irqrestore(&io_request_lock, flags);
-}
-
-#endif
-
-/***************************** COMMON CODE *******************************/
+ struct request *req;
+ blkif_response_t *bret;
+ RING_IDX i, rp;
+ unsigned long flags;
+ struct blkfront_info *info = (struct blkfront_info *)dev_id;
+
+ spin_lock_irqsave(&blkif_io_lock, flags);
+
+ if (unlikely(info->connected != BLKIF_STATE_CONNECTED || recovery)) {
+ spin_unlock_irqrestore(&blkif_io_lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ rp = info->ring.sring->rsp_prod;
+ rmb(); /* Ensure we see queued responses up to 'rp'. */
+
+ for (i = info->ring.rsp_cons; i != rp; i++) {
+ unsigned long id;
+
+ bret = RING_GET_RESPONSE(&info->ring, i);
+ id = bret->id;
+ req = (struct request *)blk_shadow[id].request;
+
+ blkif_completion(&blk_shadow[id]);
+
+ ADD_ID_TO_FREELIST(id);
+
+ switch (bret->operation) {
+ case BLKIF_OP_READ:
+ case BLKIF_OP_WRITE:
+ if (unlikely(bret->status != BLKIF_RSP_OKAY))
+ DPRINTK("Bad return from blkdev data "
+ "request: %x\n", bret->status);
+
+ BUG_ON(end_that_request_first(
+ req, (bret->status == BLKIF_RSP_OKAY),
+ req->hard_nr_sectors));
+ end_that_request_last(req);
+ break;
+ default:
+ BUG();
+ }
+ }
+
+ info->ring.rsp_cons = i;
+
+ kick_pending_request_queues(info);
+
+ spin_unlock_irqrestore(&blkif_io_lock, flags);
+
+ return IRQ_HANDLED;
+}
static void blkif_free(struct blkfront_info *info)
{
- /* Prevent new requests being issued until we fix things up. */
- spin_lock_irq(&blkif_io_lock);
- info->connected = BLKIF_STATE_DISCONNECTED;
- spin_unlock_irq(&blkif_io_lock);
-
- /* Free resources associated with old device channel. */
- if ( info->ring.sring != NULL )
- {
- free_page((unsigned long)info->ring.sring);
- info->ring.sring = NULL;
- }
- unbind_evtchn_from_irqhandler(info->evtchn, NULL);
- info->evtchn = 0;
+ /* Prevent new requests being issued until we fix things up. */
+ spin_lock_irq(&blkif_io_lock);
+ info->connected = BLKIF_STATE_DISCONNECTED;
+ spin_unlock_irq(&blkif_io_lock);
+
+ /* Free resources associated with old device channel. */
+ if (info->ring.sring != NULL) {
+ free_page((unsigned long)info->ring.sring);
+ info->ring.sring = NULL;
+ }
+ unbind_evtchn_from_irqhandler(info->evtchn, NULL);
+ info->evtchn = 0;
}
static void blkif_recover(struct blkfront_info *info)
{
- int i;
- blkif_request_t *req;
- struct blk_shadow *copy;
- int j;
-
- /* Stage 1: Make a safe copy of the shadow state. */
- copy = (struct blk_shadow *)kmalloc(sizeof(blk_shadow), GFP_KERNEL);
- BUG_ON(copy == NULL);
- memcpy(copy, blk_shadow, sizeof(blk_shadow));
-
- /* Stage 2: Set up free list. */
- memset(&blk_shadow, 0, sizeof(blk_shadow));
- for ( i = 0; i < BLK_RING_SIZE; i++ )
- blk_shadow[i].req.id = i+1;
- blk_shadow_free = info->ring.req_prod_pvt;
- blk_shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
-
- /* Stage 3: Find pending requests and requeue them. */
- for ( i = 0; i < BLK_RING_SIZE; i++ )
- {
- /* Not in use? */
- if ( copy[i].request == 0 )
- continue;
-
- /* Grab a request slot and unpickle shadow state into it. */
- req = RING_GET_REQUEST(
- &info->ring, info->ring.req_prod_pvt);
- unpickle_request(req, ©[i]);
-
- /* We get a new request id, and must reset the shadow state. */
- req->id = GET_ID_FROM_FREELIST();
- memcpy(&blk_shadow[req->id], ©[i], sizeof(copy[i]));
-
- /* Rewrite any grant references invalidated by suspend/resume. */
- for ( j = 0; j < req->nr_segments; j++ )
- {
- if ( req->frame_and_sects[j] & GRANTREF_INVALID )
- gnttab_grant_foreign_access_ref(
- blkif_gref_from_fas(req->frame_and_sects[j]),
- info->backend_id,
- blk_shadow[req->id].frame[j],
- rq_data_dir((struct request *)
- blk_shadow[req->id].request));
- req->frame_and_sects[j] &= ~GRANTREF_INVALID;
- }
- blk_shadow[req->id].req = *req;
-
- info->ring.req_prod_pvt++;
- }
-
- kfree(copy);
-
- recovery = 0;
-
- /* info->ring->req_prod will be set when we flush_requests().*/
- wmb();
-
- /* Kicks things back into life. */
- flush_requests(info);
-
- /* Now safe to left other people use the interface. */
- info->connected = BLKIF_STATE_CONNECTED;
+ int i;
+ blkif_request_t *req;
+ struct blk_shadow *copy;
+ int j;
+
+ /* Stage 1: Make a safe copy of the shadow state. */
+ copy = (struct blk_shadow *)kmalloc(sizeof(blk_shadow), GFP_KERNEL);
+ BUG_ON(copy == NULL);
+ memcpy(copy, blk_shadow, sizeof(blk_shadow));
+
+ /* Stage 2: Set up free list. */
+ memset(&blk_shadow, 0, sizeof(blk_shadow));
+ for (i = 0; i < BLK_RING_SIZE; i++)
+ blk_shadow[i].req.id = i+1;
+ blk_shadow_free = info->ring.req_prod_pvt;
+ blk_shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
+
+ /* Stage 3: Find pending requests and requeue them. */
+ for (i = 0; i < BLK_RING_SIZE; i++) {
+ /* Not in use? */
+ if (copy[i].request == 0)
+ continue;
+
+ /* Grab a request slot and unpickle shadow state into it. */
+ req = RING_GET_REQUEST(
+ &info->ring, info->ring.req_prod_pvt);
+ unpickle_request(req, ©[i]);
+
+ /* We get a new request id, and must reset the shadow state. */
+ req->id = GET_ID_FROM_FREELIST();
+ memcpy(&blk_shadow[req->id], ©[i], sizeof(copy[i]));
+
+ /* Rewrite any grant references invalidated by susp/resume. */
+ for (j = 0; j < req->nr_segments; j++) {
+ if ( req->frame_and_sects[j] & GRANTREF_INVALID )
+ gnttab_grant_foreign_access_ref(
+ blkif_gref_from_fas(
+ req->frame_and_sects[j]),
+ info->backend_id,
+ blk_shadow[req->id].frame[j],
+ rq_data_dir(
+ (struct request *)
+ blk_shadow[req->id].request));
+ req->frame_and_sects[j] &= ~GRANTREF_INVALID;
+ }
+ blk_shadow[req->id].req = *req;
+
+ info->ring.req_prod_pvt++;
+ }
+
+ kfree(copy);
+
+ recovery = 0;
+
+ /* info->ring->req_prod will be set when we flush_requests().*/
+ wmb();
+
+ /* Kicks things back into life. */
+ flush_requests(info);
+
+ /* Now safe to left other people use the interface. */
+ info->connected = BLKIF_STATE_CONNECTED;
}
static void blkif_connect(struct blkfront_info *info, u16 evtchn)
{
- int err = 0;
-
- info->evtchn = evtchn;
-
- err = bind_evtchn_to_irqhandler(
- info->evtchn, blkif_int, SA_SAMPLE_RANDOM, "blkif", info);
- if ( err != 0 )
- {
- WPRINTK("bind_evtchn_to_irqhandler failed (err=%d)\n", err);
- return;
- }
+ int err = 0;
+
+ info->evtchn = evtchn;
+
+ err = bind_evtchn_to_irqhandler(
+ info->evtchn, blkif_int, SA_SAMPLE_RANDOM, "blkif", info);
+ if (err != 0) {
+ WPRINTK("bind_evtchn_to_irqhandler failed (err=%d)\n", err);
+ return;
+ }
}
@@ -1329,55 +730,65 @@
static int wait_for_blkif(void)
{
- int err = 0;
- int i;
-
- /*
- * We should figure out how many and which devices we need to
- * proceed and only wait for those. For now, continue once the
- * first device is around.
- */
- for ( i=0; blkif_state != BLKIF_STATE_CONNECTED && (i < 10*HZ); i++ )
- {
- set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(1);
- }
-
- if ( blkif_state != BLKIF_STATE_CONNECTED )
- {
- WPRINTK("Timeout connecting to device!\n");
- err = -ENOSYS;
- }
- return err;
+ int err = 0;
+ int i;
+
+ /*
+ * We should figure out how many and which devices we need to
+ * proceed and only wait for those. For now, continue once the
+ * first device is around.
+ */
+ for (i = 0; blkif_state != BLKIF_STATE_CONNECTED && (i < 10*HZ); i++) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+
+ if (blkif_state != BLKIF_STATE_CONNECTED) {
+ WPRINTK("Timeout connecting to device!\n");
+ err = -ENOSYS;
+ }
+ return err;
}
static int __init xlblk_init(void)
{
- int i;
-
- if ( (xen_start_info.flags & SIF_INITDOMAIN) ||
- (xen_start_info.flags & SIF_BLK_BE_DOMAIN) )
- return 0;
-
- IPRINTK("Initialising virtual block device driver\n");
-
- blk_shadow_free = 0;
- memset(blk_shadow, 0, sizeof(blk_shadow));
- for ( i = 0; i < BLK_RING_SIZE; i++ )
- blk_shadow[i].req.id = i+1;
- blk_shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
-
- init_blk_xenbus();
-
- wait_for_blkif();
-
- return 0;
-}
+ int i;
+
+ if ((xen_start_info.flags & SIF_INITDOMAIN)
+ || (xen_start_info.flags & SIF_BLK_BE_DOMAIN) )
+ return 0;
+
+ IPRINTK("Initialising virtual block device driver\n");
+
+ blk_shadow_free = 0;
+ memset(blk_shadow, 0, sizeof(blk_shadow));
+ for (i = 0; i < BLK_RING_SIZE; i++)
+ blk_shadow[i].req.id = i+1;
+ blk_shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
+
+ init_blk_xenbus();
+
+ wait_for_blkif();
+
+ return 0;
+}
+
+module_init(xlblk_init);
static void blkif_completion(struct blk_shadow *s)
{
- int i;
- for ( i = 0; i < s->req.nr_segments; i++ )
- gnttab_free_grant_reference(
- blkif_gref_from_fas(s->req.frame_and_sects[i]));
-}
+ int i;
+ for (i = 0; i < s->req.nr_segments; i++)
+ gnttab_free_grant_reference(
+ blkif_gref_from_fas(s->req.frame_and_sects[i]));
+}
+
+/*
+ * Local variables:
+ * c-file-style: "linux"
+ * indent-tabs-mode: t
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * tab-width: 8
+ * End:
+ */
diff -r 15d378281a0b -r fb2fae2cc003
linux-2.6-xen-sparse/drivers/xen/blkfront/block.h
--- a/linux-2.6-xen-sparse/drivers/xen/blkfront/block.h Sat Aug 27 11:49:35 2005
+++ b/linux-2.6-xen-sparse/drivers/xen/blkfront/block.h Sun Aug 28 14:21:08 2005
@@ -116,9 +116,7 @@
blkif_front_ring_t ring;
unsigned int evtchn;
struct xlbd_major_info *mi;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
request_queue_t *rq;
-#endif
struct work_struct work;
struct gnttab_free_callback callback;
};
_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |