| Current Path : /sys/dev/xen/blkfront/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/dev/xen/blkfront/block.h |
/*
* XenBSD block device driver
*
* Copyright (c) 2009 Scott Long, Yahoo!
* Copyright (c) 2009 Frank Suchomel, Citrix
* Copyright (c) 2009 Doug F. Rabson, Citrix
* Copyright (c) 2005 Kip Macy
* Copyright (c) 2003-2004, Keir Fraser & Steve Hand
* Modifications by Mark A. Williamson are (c) Intel Research Cambridge
*
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* $FreeBSD: release/9.1.0/sys/dev/xen/blkfront/block.h 231851 2012-02-17 01:45:49Z gibbs $
*/
#ifndef __XEN_DRIVERS_BLOCK_H__
#define __XEN_DRIVERS_BLOCK_H__
#include <xen/blkif.h>
/**
* Given a number of blkif segments, compute the maximum I/O size supported.
*
* \note This calculation assumes that all but the first and last segments
* of the I/O are fully utilized.
*
* \note We reserve a segement from the maximum supported by the transport to
* guarantee we can handle an unaligned transfer without the need to
* use a bounce buffer.
*/
#define XBF_SEGS_TO_SIZE(segs) \
(((segs) - 1) * PAGE_SIZE)
/**
* Compute the maximum number of blkif segments requried to represent
* an I/O of the given size.
*
* \note This calculation assumes that all but the first and last segments
* of the I/O are fully utilized.
*
* \note We reserve a segement to guarantee we can handle an unaligned
* transfer without the need to use a bounce buffer.
*/
#define XBF_SIZE_TO_SEGS(size) \
((size / PAGE_SIZE) + 1)
/**
* The maximum number of outstanding requests blocks (request headers plus
* additional segment blocks) we will allow in a negotiated block-front/back
* communication channel.
*/
#define XBF_MAX_REQUESTS 256
/**
* The maximum mapped region size per request we will allow in a negotiated
* block-front/back communication channel.
*/
#define XBF_MAX_REQUEST_SIZE \
MIN(MAXPHYS, XBF_SEGS_TO_SIZE(BLKIF_MAX_SEGMENTS_PER_REQUEST))
/**
* The maximum number of segments (within a request header and accompanying
* segment blocks) per request we will allow in a negotiated block-front/back
* communication channel.
*/
#define XBF_MAX_SEGMENTS_PER_REQUEST \
(MIN(BLKIF_MAX_SEGMENTS_PER_REQUEST, \
XBF_SIZE_TO_SEGS(XBF_MAX_REQUEST_SIZE)))
/**
* The maximum number of shared memory ring pages we will allow in a
* negotiated block-front/back communication channel. Allow enough
* ring space for all requests to be XBF_MAX_REQUEST_SIZE'd.
*/
#define XBF_MAX_RING_PAGES \
BLKIF_RING_PAGES(BLKIF_SEGS_TO_BLOCKS(XBF_MAX_SEGMENTS_PER_REQUEST) \
* XBF_MAX_REQUESTS)
struct xlbd_type_info
{
int partn_shift;
int disks_per_major;
char *devname;
char *diskname;
};
struct xlbd_major_info
{
int major;
int index;
int usage;
struct xlbd_type_info *type;
};
struct xb_command {
TAILQ_ENTRY(xb_command) cm_link;
struct xb_softc *cm_sc;
u_int cm_flags;
#define XB_CMD_FROZEN (1<<0)
#define XB_CMD_POLLED (1<<1)
#define XB_ON_XBQ_FREE (1<<2)
#define XB_ON_XBQ_READY (1<<3)
#define XB_ON_XBQ_BUSY (1<<4)
#define XB_ON_XBQ_COMPLETE (1<<5)
#define XB_ON_XBQ_MASK ((1<<2)|(1<<3)|(1<<4)|(1<<5))
bus_dmamap_t map;
uint64_t id;
grant_ref_t *sg_refs;
struct bio *bp;
grant_ref_t gref_head;
void *data;
size_t datalen;
u_int nseg;
int operation;
blkif_sector_t sector_number;
int status;
void (* cm_complete)(struct xb_command *);
};
#define XBQ_FREE 0
#define XBQ_BIO 1
#define XBQ_READY 2
#define XBQ_BUSY 3
#define XBQ_COMPLETE 4
#define XBQ_COUNT 5
struct xb_qstat {
uint32_t q_length;
uint32_t q_max;
};
union xb_statrequest {
uint32_t ms_item;
struct xb_qstat ms_qstat;
};
/*
* We have one of these per vbd, whether ide, scsi or 'other'.
*/
struct xb_softc {
device_t xb_dev;
struct disk *xb_disk; /* disk params */
struct bio_queue_head xb_bioq; /* sort queue */
int xb_unit;
int xb_flags;
#define XB_OPEN (1<<0) /* drive is open (can't shut down) */
#define XB_BARRIER (1 << 1) /* backend supports barriers */
#define XB_READY (1 << 2) /* Is ready */
#define XB_FROZEN (1 << 3) /* Waiting for resources */
int vdevice;
int connected;
u_int ring_pages;
uint32_t max_requests;
uint32_t max_request_segments;
uint32_t max_request_blocks;
uint32_t max_request_size;
grant_ref_t ring_ref[XBF_MAX_RING_PAGES];
blkif_front_ring_t ring;
unsigned int irq;
struct gnttab_free_callback callback;
TAILQ_HEAD(,xb_command) cm_free;
TAILQ_HEAD(,xb_command) cm_ready;
TAILQ_HEAD(,xb_command) cm_busy;
TAILQ_HEAD(,xb_command) cm_complete;
struct xb_qstat xb_qstat[XBQ_COUNT];
bus_dma_tag_t xb_io_dmat;
/**
* The number of people holding this device open. We won't allow a
* hot-unplug unless this is 0.
*/
int users;
struct mtx xb_io_lock;
struct xb_command *shadow;
};
int xlvbd_add(struct xb_softc *, blkif_sector_t sectors, int device,
uint16_t vdisk_info, unsigned long sector_size);
void xlvbd_del(struct xb_softc *);
#define XBQ_ADD(sc, qname) \
do { \
struct xb_qstat *qs; \
\
qs = &(sc)->xb_qstat[qname]; \
qs->q_length++; \
if (qs->q_length > qs->q_max) \
qs->q_max = qs->q_length; \
} while (0)
#define XBQ_REMOVE(sc, qname) (sc)->xb_qstat[qname].q_length--
#define XBQ_INIT(sc, qname) \
do { \
sc->xb_qstat[qname].q_length = 0; \
sc->xb_qstat[qname].q_max = 0; \
} while (0)
#define XBQ_COMMAND_QUEUE(name, index) \
static __inline void \
xb_initq_ ## name (struct xb_softc *sc) \
{ \
TAILQ_INIT(&sc->cm_ ## name); \
XBQ_INIT(sc, index); \
} \
static __inline void \
xb_enqueue_ ## name (struct xb_command *cm) \
{ \
if ((cm->cm_flags & XB_ON_XBQ_MASK) != 0) { \
printf("command %p is on another queue, " \
"flags = %#x\n", cm, cm->cm_flags); \
panic("command is on another queue"); \
} \
TAILQ_INSERT_TAIL(&cm->cm_sc->cm_ ## name, cm, cm_link); \
cm->cm_flags |= XB_ON_ ## index; \
XBQ_ADD(cm->cm_sc, index); \
} \
static __inline void \
xb_requeue_ ## name (struct xb_command *cm) \
{ \
if ((cm->cm_flags & XB_ON_XBQ_MASK) != 0) { \
printf("command %p is on another queue, " \
"flags = %#x\n", cm, cm->cm_flags); \
panic("command is on another queue"); \
} \
TAILQ_INSERT_HEAD(&cm->cm_sc->cm_ ## name, cm, cm_link); \
cm->cm_flags |= XB_ON_ ## index; \
XBQ_ADD(cm->cm_sc, index); \
} \
static __inline struct xb_command * \
xb_dequeue_ ## name (struct xb_softc *sc) \
{ \
struct xb_command *cm; \
\
if ((cm = TAILQ_FIRST(&sc->cm_ ## name)) != NULL) { \
if ((cm->cm_flags & XB_ON_XBQ_MASK) != \
XB_ON_ ## index) { \
printf("command %p not in queue, " \
"flags = %#x, bit = %#x\n", cm, \
cm->cm_flags, XB_ON_ ## index); \
panic("command not in queue"); \
} \
TAILQ_REMOVE(&sc->cm_ ## name, cm, cm_link); \
cm->cm_flags &= ~XB_ON_ ## index; \
XBQ_REMOVE(sc, index); \
} \
return (cm); \
} \
static __inline void \
xb_remove_ ## name (struct xb_command *cm) \
{ \
if ((cm->cm_flags & XB_ON_XBQ_MASK) != XB_ON_ ## index){\
printf("command %p not in queue, flags = %#x, " \
"bit = %#x\n", cm, cm->cm_flags, \
XB_ON_ ## index); \
panic("command not in queue"); \
} \
TAILQ_REMOVE(&cm->cm_sc->cm_ ## name, cm, cm_link); \
cm->cm_flags &= ~XB_ON_ ## index; \
XBQ_REMOVE(cm->cm_sc, index); \
} \
struct hack
XBQ_COMMAND_QUEUE(free, XBQ_FREE);
XBQ_COMMAND_QUEUE(ready, XBQ_READY);
XBQ_COMMAND_QUEUE(busy, XBQ_BUSY);
XBQ_COMMAND_QUEUE(complete, XBQ_COMPLETE);
static __inline void
xb_initq_bio(struct xb_softc *sc)
{
bioq_init(&sc->xb_bioq);
XBQ_INIT(sc, XBQ_BIO);
}
static __inline void
xb_enqueue_bio(struct xb_softc *sc, struct bio *bp)
{
bioq_insert_tail(&sc->xb_bioq, bp);
XBQ_ADD(sc, XBQ_BIO);
}
static __inline void
xb_requeue_bio(struct xb_softc *sc, struct bio *bp)
{
bioq_insert_head(&sc->xb_bioq, bp);
XBQ_ADD(sc, XBQ_BIO);
}
static __inline struct bio *
xb_dequeue_bio(struct xb_softc *sc)
{
struct bio *bp;
if ((bp = bioq_first(&sc->xb_bioq)) != NULL) {
bioq_remove(&sc->xb_bioq, bp);
XBQ_REMOVE(sc, XBQ_BIO);
}
return (bp);
}
#endif /* __XEN_DRIVERS_BLOCK_H__ */