06d381484f
* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: net: xen-netback: use API provided by xenbus module to map rings block: xen-blkback: use API provided by xenbus module to map rings xen: use generic functions instead of xen_{alloc, free}_vm_area()
803 lines
19 KiB
C
803 lines
19 KiB
C
/* Xenbus code for blkif backend
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Copyright (C) 2005 Rusty Russell <rusty@rustcorp.com.au>
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Copyright (C) 2005 XenSource Ltd
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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*/
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#include <stdarg.h>
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#include <linux/module.h>
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#include <linux/kthread.h>
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#include <xen/events.h>
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#include <xen/grant_table.h>
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#include "common.h"
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struct backend_info {
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struct xenbus_device *dev;
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struct xen_blkif *blkif;
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struct xenbus_watch backend_watch;
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unsigned major;
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unsigned minor;
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char *mode;
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};
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static struct kmem_cache *xen_blkif_cachep;
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static void connect(struct backend_info *);
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static int connect_ring(struct backend_info *);
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static void backend_changed(struct xenbus_watch *, const char **,
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unsigned int);
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struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be)
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{
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return be->dev;
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}
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static int blkback_name(struct xen_blkif *blkif, char *buf)
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{
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char *devpath, *devname;
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struct xenbus_device *dev = blkif->be->dev;
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devpath = xenbus_read(XBT_NIL, dev->nodename, "dev", NULL);
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if (IS_ERR(devpath))
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return PTR_ERR(devpath);
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devname = strstr(devpath, "/dev/");
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if (devname != NULL)
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devname += strlen("/dev/");
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else
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devname = devpath;
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snprintf(buf, TASK_COMM_LEN, "blkback.%d.%s", blkif->domid, devname);
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kfree(devpath);
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return 0;
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}
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static void xen_update_blkif_status(struct xen_blkif *blkif)
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{
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int err;
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char name[TASK_COMM_LEN];
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/* Not ready to connect? */
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if (!blkif->irq || !blkif->vbd.bdev)
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return;
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/* Already connected? */
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if (blkif->be->dev->state == XenbusStateConnected)
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return;
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/* Attempt to connect: exit if we fail to. */
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connect(blkif->be);
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if (blkif->be->dev->state != XenbusStateConnected)
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return;
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err = blkback_name(blkif, name);
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if (err) {
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xenbus_dev_error(blkif->be->dev, err, "get blkback dev name");
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return;
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}
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err = filemap_write_and_wait(blkif->vbd.bdev->bd_inode->i_mapping);
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if (err) {
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xenbus_dev_error(blkif->be->dev, err, "block flush");
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return;
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}
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invalidate_inode_pages2(blkif->vbd.bdev->bd_inode->i_mapping);
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blkif->xenblkd = kthread_run(xen_blkif_schedule, blkif, name);
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if (IS_ERR(blkif->xenblkd)) {
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err = PTR_ERR(blkif->xenblkd);
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blkif->xenblkd = NULL;
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xenbus_dev_error(blkif->be->dev, err, "start xenblkd");
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}
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}
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static struct xen_blkif *xen_blkif_alloc(domid_t domid)
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{
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struct xen_blkif *blkif;
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blkif = kmem_cache_alloc(xen_blkif_cachep, GFP_KERNEL);
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if (!blkif)
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return ERR_PTR(-ENOMEM);
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memset(blkif, 0, sizeof(*blkif));
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blkif->domid = domid;
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spin_lock_init(&blkif->blk_ring_lock);
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atomic_set(&blkif->refcnt, 1);
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init_waitqueue_head(&blkif->wq);
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init_completion(&blkif->drain_complete);
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atomic_set(&blkif->drain, 0);
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blkif->st_print = jiffies;
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init_waitqueue_head(&blkif->waiting_to_free);
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return blkif;
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}
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static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page,
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unsigned int evtchn)
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{
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int err;
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/* Already connected through? */
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if (blkif->irq)
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return 0;
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err = xenbus_map_ring_valloc(blkif->be->dev, shared_page, &blkif->blk_ring);
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if (err < 0)
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return err;
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switch (blkif->blk_protocol) {
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case BLKIF_PROTOCOL_NATIVE:
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{
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struct blkif_sring *sring;
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sring = (struct blkif_sring *)blkif->blk_ring;
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BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE);
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break;
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}
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case BLKIF_PROTOCOL_X86_32:
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{
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struct blkif_x86_32_sring *sring_x86_32;
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sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring;
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BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE);
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break;
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}
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case BLKIF_PROTOCOL_X86_64:
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{
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struct blkif_x86_64_sring *sring_x86_64;
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sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring;
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BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE);
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break;
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}
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default:
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BUG();
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}
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err = bind_interdomain_evtchn_to_irqhandler(blkif->domid, evtchn,
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xen_blkif_be_int, 0,
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"blkif-backend", blkif);
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if (err < 0) {
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xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring);
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blkif->blk_rings.common.sring = NULL;
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return err;
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}
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blkif->irq = err;
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return 0;
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}
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static void xen_blkif_disconnect(struct xen_blkif *blkif)
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{
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if (blkif->xenblkd) {
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kthread_stop(blkif->xenblkd);
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blkif->xenblkd = NULL;
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}
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atomic_dec(&blkif->refcnt);
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wait_event(blkif->waiting_to_free, atomic_read(&blkif->refcnt) == 0);
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atomic_inc(&blkif->refcnt);
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if (blkif->irq) {
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unbind_from_irqhandler(blkif->irq, blkif);
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blkif->irq = 0;
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}
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if (blkif->blk_rings.common.sring) {
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xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring);
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blkif->blk_rings.common.sring = NULL;
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}
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}
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void xen_blkif_free(struct xen_blkif *blkif)
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{
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if (!atomic_dec_and_test(&blkif->refcnt))
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BUG();
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kmem_cache_free(xen_blkif_cachep, blkif);
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}
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int __init xen_blkif_interface_init(void)
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{
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xen_blkif_cachep = kmem_cache_create("blkif_cache",
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sizeof(struct xen_blkif),
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0, 0, NULL);
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if (!xen_blkif_cachep)
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return -ENOMEM;
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return 0;
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}
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/*
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* sysfs interface for VBD I/O requests
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*/
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#define VBD_SHOW(name, format, args...) \
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static ssize_t show_##name(struct device *_dev, \
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struct device_attribute *attr, \
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char *buf) \
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{ \
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struct xenbus_device *dev = to_xenbus_device(_dev); \
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struct backend_info *be = dev_get_drvdata(&dev->dev); \
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\
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return sprintf(buf, format, ##args); \
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} \
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static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
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VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req);
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VBD_SHOW(rd_req, "%d\n", be->blkif->st_rd_req);
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VBD_SHOW(wr_req, "%d\n", be->blkif->st_wr_req);
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VBD_SHOW(f_req, "%d\n", be->blkif->st_f_req);
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VBD_SHOW(ds_req, "%d\n", be->blkif->st_ds_req);
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VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect);
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VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect);
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static struct attribute *xen_vbdstat_attrs[] = {
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&dev_attr_oo_req.attr,
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&dev_attr_rd_req.attr,
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&dev_attr_wr_req.attr,
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&dev_attr_f_req.attr,
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&dev_attr_ds_req.attr,
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&dev_attr_rd_sect.attr,
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&dev_attr_wr_sect.attr,
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NULL
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};
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static struct attribute_group xen_vbdstat_group = {
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.name = "statistics",
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.attrs = xen_vbdstat_attrs,
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};
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VBD_SHOW(physical_device, "%x:%x\n", be->major, be->minor);
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VBD_SHOW(mode, "%s\n", be->mode);
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int xenvbd_sysfs_addif(struct xenbus_device *dev)
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{
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int error;
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error = device_create_file(&dev->dev, &dev_attr_physical_device);
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if (error)
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goto fail1;
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error = device_create_file(&dev->dev, &dev_attr_mode);
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if (error)
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goto fail2;
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error = sysfs_create_group(&dev->dev.kobj, &xen_vbdstat_group);
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if (error)
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goto fail3;
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return 0;
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fail3: sysfs_remove_group(&dev->dev.kobj, &xen_vbdstat_group);
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fail2: device_remove_file(&dev->dev, &dev_attr_mode);
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fail1: device_remove_file(&dev->dev, &dev_attr_physical_device);
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return error;
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}
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void xenvbd_sysfs_delif(struct xenbus_device *dev)
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{
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sysfs_remove_group(&dev->dev.kobj, &xen_vbdstat_group);
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device_remove_file(&dev->dev, &dev_attr_mode);
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device_remove_file(&dev->dev, &dev_attr_physical_device);
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}
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static void xen_vbd_free(struct xen_vbd *vbd)
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{
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if (vbd->bdev)
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blkdev_put(vbd->bdev, vbd->readonly ? FMODE_READ : FMODE_WRITE);
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vbd->bdev = NULL;
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}
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static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
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unsigned major, unsigned minor, int readonly,
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int cdrom)
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{
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struct xen_vbd *vbd;
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struct block_device *bdev;
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struct request_queue *q;
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vbd = &blkif->vbd;
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vbd->handle = handle;
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vbd->readonly = readonly;
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vbd->type = 0;
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vbd->pdevice = MKDEV(major, minor);
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bdev = blkdev_get_by_dev(vbd->pdevice, vbd->readonly ?
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FMODE_READ : FMODE_WRITE, NULL);
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if (IS_ERR(bdev)) {
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DPRINTK("xen_vbd_create: device %08x could not be opened.\n",
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vbd->pdevice);
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return -ENOENT;
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}
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vbd->bdev = bdev;
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if (vbd->bdev->bd_disk == NULL) {
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DPRINTK("xen_vbd_create: device %08x doesn't exist.\n",
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vbd->pdevice);
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xen_vbd_free(vbd);
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return -ENOENT;
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}
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vbd->size = vbd_sz(vbd);
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if (vbd->bdev->bd_disk->flags & GENHD_FL_CD || cdrom)
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vbd->type |= VDISK_CDROM;
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if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
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vbd->type |= VDISK_REMOVABLE;
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q = bdev_get_queue(bdev);
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if (q && q->flush_flags)
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vbd->flush_support = true;
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DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
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handle, blkif->domid);
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return 0;
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}
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static int xen_blkbk_remove(struct xenbus_device *dev)
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{
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struct backend_info *be = dev_get_drvdata(&dev->dev);
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DPRINTK("");
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if (be->major || be->minor)
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xenvbd_sysfs_delif(dev);
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if (be->backend_watch.node) {
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unregister_xenbus_watch(&be->backend_watch);
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kfree(be->backend_watch.node);
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be->backend_watch.node = NULL;
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}
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if (be->blkif) {
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xen_blkif_disconnect(be->blkif);
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xen_vbd_free(&be->blkif->vbd);
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xen_blkif_free(be->blkif);
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be->blkif = NULL;
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}
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kfree(be);
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dev_set_drvdata(&dev->dev, NULL);
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return 0;
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}
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int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
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struct backend_info *be, int state)
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{
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struct xenbus_device *dev = be->dev;
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int err;
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err = xenbus_printf(xbt, dev->nodename, "feature-flush-cache",
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"%d", state);
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if (err)
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xenbus_dev_fatal(dev, err, "writing feature-flush-cache");
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return err;
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}
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int xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info *be)
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{
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struct xenbus_device *dev = be->dev;
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struct xen_blkif *blkif = be->blkif;
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char *type;
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int err;
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int state = 0;
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type = xenbus_read(XBT_NIL, dev->nodename, "type", NULL);
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if (!IS_ERR(type)) {
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if (strncmp(type, "file", 4) == 0) {
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state = 1;
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blkif->blk_backend_type = BLKIF_BACKEND_FILE;
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}
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if (strncmp(type, "phy", 3) == 0) {
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struct block_device *bdev = be->blkif->vbd.bdev;
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struct request_queue *q = bdev_get_queue(bdev);
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if (blk_queue_discard(q)) {
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err = xenbus_printf(xbt, dev->nodename,
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"discard-granularity", "%u",
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q->limits.discard_granularity);
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if (err) {
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xenbus_dev_fatal(dev, err,
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"writing discard-granularity");
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goto kfree;
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}
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err = xenbus_printf(xbt, dev->nodename,
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"discard-alignment", "%u",
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q->limits.discard_alignment);
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if (err) {
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xenbus_dev_fatal(dev, err,
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"writing discard-alignment");
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goto kfree;
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}
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state = 1;
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blkif->blk_backend_type = BLKIF_BACKEND_PHY;
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}
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}
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} else {
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err = PTR_ERR(type);
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xenbus_dev_fatal(dev, err, "reading type");
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goto out;
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}
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err = xenbus_printf(xbt, dev->nodename, "feature-discard",
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"%d", state);
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if (err)
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xenbus_dev_fatal(dev, err, "writing feature-discard");
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kfree:
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kfree(type);
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out:
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return err;
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}
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int xen_blkbk_barrier(struct xenbus_transaction xbt,
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struct backend_info *be, int state)
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{
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struct xenbus_device *dev = be->dev;
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int err;
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err = xenbus_printf(xbt, dev->nodename, "feature-barrier",
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"%d", state);
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if (err)
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xenbus_dev_fatal(dev, err, "writing feature-barrier");
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return err;
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}
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/*
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* Entry point to this code when a new device is created. Allocate the basic
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* structures, and watch the store waiting for the hotplug scripts to tell us
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* the device's physical major and minor numbers. Switch to InitWait.
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*/
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static int xen_blkbk_probe(struct xenbus_device *dev,
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const struct xenbus_device_id *id)
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{
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int err;
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struct backend_info *be = kzalloc(sizeof(struct backend_info),
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GFP_KERNEL);
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if (!be) {
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xenbus_dev_fatal(dev, -ENOMEM,
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"allocating backend structure");
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return -ENOMEM;
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}
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be->dev = dev;
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dev_set_drvdata(&dev->dev, be);
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be->blkif = xen_blkif_alloc(dev->otherend_id);
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if (IS_ERR(be->blkif)) {
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err = PTR_ERR(be->blkif);
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be->blkif = NULL;
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xenbus_dev_fatal(dev, err, "creating block interface");
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goto fail;
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}
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/* setup back pointer */
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be->blkif->be = be;
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err = xenbus_watch_pathfmt(dev, &be->backend_watch, backend_changed,
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"%s/%s", dev->nodename, "physical-device");
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if (err)
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goto fail;
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err = xenbus_switch_state(dev, XenbusStateInitWait);
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if (err)
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goto fail;
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return 0;
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fail:
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DPRINTK("failed");
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xen_blkbk_remove(dev);
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return err;
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}
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/*
|
|
* Callback received when the hotplug scripts have placed the physical-device
|
|
* node. Read it and the mode node, and create a vbd. If the frontend is
|
|
* ready, connect.
|
|
*/
|
|
static void backend_changed(struct xenbus_watch *watch,
|
|
const char **vec, unsigned int len)
|
|
{
|
|
int err;
|
|
unsigned major;
|
|
unsigned minor;
|
|
struct backend_info *be
|
|
= container_of(watch, struct backend_info, backend_watch);
|
|
struct xenbus_device *dev = be->dev;
|
|
int cdrom = 0;
|
|
char *device_type;
|
|
|
|
DPRINTK("");
|
|
|
|
err = xenbus_scanf(XBT_NIL, dev->nodename, "physical-device", "%x:%x",
|
|
&major, &minor);
|
|
if (XENBUS_EXIST_ERR(err)) {
|
|
/*
|
|
* Since this watch will fire once immediately after it is
|
|
* registered, we expect this. Ignore it, and wait for the
|
|
* hotplug scripts.
|
|
*/
|
|
return;
|
|
}
|
|
if (err != 2) {
|
|
xenbus_dev_fatal(dev, err, "reading physical-device");
|
|
return;
|
|
}
|
|
|
|
if ((be->major || be->minor) &&
|
|
((be->major != major) || (be->minor != minor))) {
|
|
pr_warn(DRV_PFX "changing physical device (from %x:%x to %x:%x) not supported.\n",
|
|
be->major, be->minor, major, minor);
|
|
return;
|
|
}
|
|
|
|
be->mode = xenbus_read(XBT_NIL, dev->nodename, "mode", NULL);
|
|
if (IS_ERR(be->mode)) {
|
|
err = PTR_ERR(be->mode);
|
|
be->mode = NULL;
|
|
xenbus_dev_fatal(dev, err, "reading mode");
|
|
return;
|
|
}
|
|
|
|
device_type = xenbus_read(XBT_NIL, dev->otherend, "device-type", NULL);
|
|
if (!IS_ERR(device_type)) {
|
|
cdrom = strcmp(device_type, "cdrom") == 0;
|
|
kfree(device_type);
|
|
}
|
|
|
|
if (be->major == 0 && be->minor == 0) {
|
|
/* Front end dir is a number, which is used as the handle. */
|
|
|
|
char *p = strrchr(dev->otherend, '/') + 1;
|
|
long handle;
|
|
err = strict_strtoul(p, 0, &handle);
|
|
if (err)
|
|
return;
|
|
|
|
be->major = major;
|
|
be->minor = minor;
|
|
|
|
err = xen_vbd_create(be->blkif, handle, major, minor,
|
|
(NULL == strchr(be->mode, 'w')), cdrom);
|
|
if (err) {
|
|
be->major = 0;
|
|
be->minor = 0;
|
|
xenbus_dev_fatal(dev, err, "creating vbd structure");
|
|
return;
|
|
}
|
|
|
|
err = xenvbd_sysfs_addif(dev);
|
|
if (err) {
|
|
xen_vbd_free(&be->blkif->vbd);
|
|
be->major = 0;
|
|
be->minor = 0;
|
|
xenbus_dev_fatal(dev, err, "creating sysfs entries");
|
|
return;
|
|
}
|
|
|
|
/* We're potentially connected now */
|
|
xen_update_blkif_status(be->blkif);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Callback received when the frontend's state changes.
|
|
*/
|
|
static void frontend_changed(struct xenbus_device *dev,
|
|
enum xenbus_state frontend_state)
|
|
{
|
|
struct backend_info *be = dev_get_drvdata(&dev->dev);
|
|
int err;
|
|
|
|
DPRINTK("%s", xenbus_strstate(frontend_state));
|
|
|
|
switch (frontend_state) {
|
|
case XenbusStateInitialising:
|
|
if (dev->state == XenbusStateClosed) {
|
|
pr_info(DRV_PFX "%s: prepare for reconnect\n",
|
|
dev->nodename);
|
|
xenbus_switch_state(dev, XenbusStateInitWait);
|
|
}
|
|
break;
|
|
|
|
case XenbusStateInitialised:
|
|
case XenbusStateConnected:
|
|
/*
|
|
* Ensure we connect even when two watches fire in
|
|
* close successsion and we miss the intermediate value
|
|
* of frontend_state.
|
|
*/
|
|
if (dev->state == XenbusStateConnected)
|
|
break;
|
|
|
|
/*
|
|
* Enforce precondition before potential leak point.
|
|
* xen_blkif_disconnect() is idempotent.
|
|
*/
|
|
xen_blkif_disconnect(be->blkif);
|
|
|
|
err = connect_ring(be);
|
|
if (err)
|
|
break;
|
|
xen_update_blkif_status(be->blkif);
|
|
break;
|
|
|
|
case XenbusStateClosing:
|
|
xenbus_switch_state(dev, XenbusStateClosing);
|
|
break;
|
|
|
|
case XenbusStateClosed:
|
|
xen_blkif_disconnect(be->blkif);
|
|
xenbus_switch_state(dev, XenbusStateClosed);
|
|
if (xenbus_dev_is_online(dev))
|
|
break;
|
|
/* fall through if not online */
|
|
case XenbusStateUnknown:
|
|
/* implies xen_blkif_disconnect() via xen_blkbk_remove() */
|
|
device_unregister(&dev->dev);
|
|
break;
|
|
|
|
default:
|
|
xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
|
|
frontend_state);
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/* ** Connection ** */
|
|
|
|
|
|
/*
|
|
* Write the physical details regarding the block device to the store, and
|
|
* switch to Connected state.
|
|
*/
|
|
static void connect(struct backend_info *be)
|
|
{
|
|
struct xenbus_transaction xbt;
|
|
int err;
|
|
struct xenbus_device *dev = be->dev;
|
|
|
|
DPRINTK("%s", dev->otherend);
|
|
|
|
/* Supply the information about the device the frontend needs */
|
|
again:
|
|
err = xenbus_transaction_start(&xbt);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "starting transaction");
|
|
return;
|
|
}
|
|
|
|
err = xen_blkbk_flush_diskcache(xbt, be, be->blkif->vbd.flush_support);
|
|
if (err)
|
|
goto abort;
|
|
|
|
err = xen_blkbk_discard(xbt, be);
|
|
|
|
/* If we can't advertise it is OK. */
|
|
err = xen_blkbk_barrier(xbt, be, be->blkif->vbd.flush_support);
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
|
|
(unsigned long long)vbd_sz(&be->blkif->vbd));
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "writing %s/sectors",
|
|
dev->nodename);
|
|
goto abort;
|
|
}
|
|
|
|
/* FIXME: use a typename instead */
|
|
err = xenbus_printf(xbt, dev->nodename, "info", "%u",
|
|
be->blkif->vbd.type |
|
|
(be->blkif->vbd.readonly ? VDISK_READONLY : 0));
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "writing %s/info",
|
|
dev->nodename);
|
|
goto abort;
|
|
}
|
|
err = xenbus_printf(xbt, dev->nodename, "sector-size", "%lu",
|
|
(unsigned long)
|
|
bdev_logical_block_size(be->blkif->vbd.bdev));
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "writing %s/sector-size",
|
|
dev->nodename);
|
|
goto abort;
|
|
}
|
|
|
|
err = xenbus_transaction_end(xbt, 0);
|
|
if (err == -EAGAIN)
|
|
goto again;
|
|
if (err)
|
|
xenbus_dev_fatal(dev, err, "ending transaction");
|
|
|
|
err = xenbus_switch_state(dev, XenbusStateConnected);
|
|
if (err)
|
|
xenbus_dev_fatal(dev, err, "%s: switching to Connected state",
|
|
dev->nodename);
|
|
|
|
return;
|
|
abort:
|
|
xenbus_transaction_end(xbt, 1);
|
|
}
|
|
|
|
|
|
static int connect_ring(struct backend_info *be)
|
|
{
|
|
struct xenbus_device *dev = be->dev;
|
|
unsigned long ring_ref;
|
|
unsigned int evtchn;
|
|
char protocol[64] = "";
|
|
int err;
|
|
|
|
DPRINTK("%s", dev->otherend);
|
|
|
|
err = xenbus_gather(XBT_NIL, dev->otherend, "ring-ref", "%lu",
|
|
&ring_ref, "event-channel", "%u", &evtchn, NULL);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err,
|
|
"reading %s/ring-ref and event-channel",
|
|
dev->otherend);
|
|
return err;
|
|
}
|
|
|
|
be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE;
|
|
err = xenbus_gather(XBT_NIL, dev->otherend, "protocol",
|
|
"%63s", protocol, NULL);
|
|
if (err)
|
|
strcpy(protocol, "unspecified, assuming native");
|
|
else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_NATIVE))
|
|
be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE;
|
|
else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_32))
|
|
be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_32;
|
|
else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_64))
|
|
be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_64;
|
|
else {
|
|
xenbus_dev_fatal(dev, err, "unknown fe protocol %s", protocol);
|
|
return -1;
|
|
}
|
|
pr_info(DRV_PFX "ring-ref %ld, event-channel %d, protocol %d (%s)\n",
|
|
ring_ref, evtchn, be->blkif->blk_protocol, protocol);
|
|
|
|
/* Map the shared frame, irq etc. */
|
|
err = xen_blkif_map(be->blkif, ring_ref, evtchn);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "mapping ring-ref %lu port %u",
|
|
ring_ref, evtchn);
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* ** Driver Registration ** */
|
|
|
|
|
|
static const struct xenbus_device_id xen_blkbk_ids[] = {
|
|
{ "vbd" },
|
|
{ "" }
|
|
};
|
|
|
|
|
|
static struct xenbus_driver xen_blkbk = {
|
|
.name = "vbd",
|
|
.owner = THIS_MODULE,
|
|
.ids = xen_blkbk_ids,
|
|
.probe = xen_blkbk_probe,
|
|
.remove = xen_blkbk_remove,
|
|
.otherend_changed = frontend_changed
|
|
};
|
|
|
|
|
|
int xen_blkif_xenbus_init(void)
|
|
{
|
|
return xenbus_register_backend(&xen_blkbk);
|
|
}
|