linux/drivers/block/aoe/aoe.h
Ed Cashin 896831f590 aoe: kernel thread handles I/O completions for simple locking
Make the frames the aoe driver uses to track the relationship between bios
and packets more flexible and detached, so that they can be passed to an
"aoe_ktio" thread for completion of I/O.

The frames are handled much like skbs, with a capped amount of
preallocation so that real-world use cases are likely to run smoothly and
degenerate gracefully even under memory pressure.

Decoupling I/O completion from the receive path and serializing it in a
process makes it easier to think about the correctness of the locking in
the driver, especially in the case of a remote MAC address becoming
unusable.

[dan.carpenter@oracle.com: cleanup an allocation a bit]
Signed-off-by: Ed Cashin <ecashin@coraid.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:24 +09:00

227 lines
5.4 KiB
C

/* Copyright (c) 2007 Coraid, Inc. See COPYING for GPL terms. */
#define VERSION "47"
#define AOE_MAJOR 152
#define DEVICE_NAME "aoe"
/* set AOE_PARTITIONS to 1 to use whole-disks only
* default is 16, which is 15 partitions plus the whole disk
*/
#ifndef AOE_PARTITIONS
#define AOE_PARTITIONS (16)
#endif
#define SYSMINOR(aoemajor, aoeminor) ((aoemajor) * NPERSHELF + (aoeminor))
#define AOEMAJOR(sysminor) ((sysminor) / NPERSHELF)
#define AOEMINOR(sysminor) ((sysminor) % NPERSHELF)
#define WHITESPACE " \t\v\f\n"
enum {
AOECMD_ATA,
AOECMD_CFG,
AOECMD_VEND_MIN = 0xf0,
AOEFL_RSP = (1<<3),
AOEFL_ERR = (1<<2),
AOEAFL_EXT = (1<<6),
AOEAFL_DEV = (1<<4),
AOEAFL_ASYNC = (1<<1),
AOEAFL_WRITE = (1<<0),
AOECCMD_READ = 0,
AOECCMD_TEST,
AOECCMD_PTEST,
AOECCMD_SET,
AOECCMD_FSET,
AOE_HVER = 0x10,
};
struct aoe_hdr {
unsigned char dst[6];
unsigned char src[6];
__be16 type;
unsigned char verfl;
unsigned char err;
__be16 major;
unsigned char minor;
unsigned char cmd;
__be32 tag;
};
struct aoe_atahdr {
unsigned char aflags;
unsigned char errfeat;
unsigned char scnt;
unsigned char cmdstat;
unsigned char lba0;
unsigned char lba1;
unsigned char lba2;
unsigned char lba3;
unsigned char lba4;
unsigned char lba5;
unsigned char res[2];
};
struct aoe_cfghdr {
__be16 bufcnt;
__be16 fwver;
unsigned char scnt;
unsigned char aoeccmd;
unsigned char cslen[2];
};
enum {
DEVFL_UP = 1, /* device is installed in system and ready for AoE->ATA commands */
DEVFL_TKILL = (1<<1), /* flag for timer to know when to kill self */
DEVFL_EXT = (1<<2), /* device accepts lba48 commands */
DEVFL_CLOSEWAIT = (1<<3), /* device is waiting for all closes to revalidate */
DEVFL_GDALLOC = (1<<4), /* need to alloc gendisk */
DEVFL_KICKME = (1<<5), /* slow polling network card catch */
DEVFL_NEWSIZE = (1<<6), /* need to update dev size in block layer */
BUFFL_FAIL = 1,
};
enum {
DEFAULTBCNT = 2 * 512, /* 2 sectors */
NPERSHELF = 16, /* number of slots per shelf address */
FREETAG = -1,
MIN_BUFS = 16,
NTARGETS = 8,
NAOEIFS = 8,
NSKBPOOLMAX = 128,
NFACTIVE = 17,
TIMERTICK = HZ / 10,
MINTIMER = HZ >> 2,
MAXTIMER = HZ << 1,
HELPWAIT = 20,
};
struct buf {
struct list_head bufs;
ulong stime; /* for disk stats */
ulong flags;
ulong nframesout;
ulong resid;
ulong bv_resid;
ulong bv_off;
sector_t sector;
struct bio *bio;
struct bio_vec *bv;
};
struct frame {
struct list_head head;
u32 tag;
ulong waited;
struct buf *buf;
struct aoetgt *t; /* parent target I belong to */
char *bufaddr;
ulong bcnt;
sector_t lba;
struct sk_buff *skb; /* command skb freed on module exit */
struct sk_buff *r_skb; /* response skb for async processing */
struct bio_vec *bv;
ulong bv_off;
};
struct aoeif {
struct net_device *nd;
unsigned char lost;
unsigned char lostjumbo;
ushort maxbcnt;
};
struct aoetgt {
unsigned char addr[6];
ushort nframes;
struct aoedev *d; /* parent device I belong to */
struct list_head factive[NFACTIVE]; /* hash of active frames */
struct list_head ffree; /* list of free frames */
struct aoeif ifs[NAOEIFS];
struct aoeif *ifp; /* current aoeif in use */
ushort nout;
ushort maxout;
u16 lasttag; /* last tag sent */
u16 useme;
ulong falloc;
ulong lastwadj; /* last window adjustment */
int wpkts, rpkts;
};
struct aoedev {
struct aoedev *next;
ulong sysminor;
ulong aoemajor;
u16 aoeminor;
u16 flags;
u16 nopen; /* (bd_openers isn't available without sleeping) */
u16 rttavg; /* round trip average of requests/responses */
u16 mintimer;
u16 fw_ver; /* version of blade's firmware */
struct work_struct work;/* disk create work struct */
struct gendisk *gd;
struct request_queue *blkq;
struct hd_geometry geo;
sector_t ssize;
struct timer_list timer;
spinlock_t lock;
struct sk_buff_head sendq;
struct sk_buff_head skbpool;
mempool_t *bufpool; /* for deadlock-free Buf allocation */
struct list_head bufq; /* queue of bios to work on */
struct buf *inprocess; /* the one we're currently working on */
struct aoetgt *targets[NTARGETS];
struct aoetgt **tgt; /* target in use when working */
struct aoetgt *htgt; /* target needing rexmit assistance */
ulong ntargets;
ulong kicked;
};
/* kthread tracking */
struct ktstate {
struct completion rendez;
struct task_struct *task;
wait_queue_head_t *waitq;
int (*fn) (void);
char *name;
spinlock_t *lock;
};
int aoeblk_init(void);
void aoeblk_exit(void);
void aoeblk_gdalloc(void *);
void aoedisk_rm_sysfs(struct aoedev *d);
int aoechr_init(void);
void aoechr_exit(void);
void aoechr_error(char *);
void aoecmd_work(struct aoedev *d);
void aoecmd_cfg(ushort aoemajor, unsigned char aoeminor);
struct sk_buff *aoecmd_ata_rsp(struct sk_buff *);
void aoecmd_cfg_rsp(struct sk_buff *);
void aoecmd_sleepwork(struct work_struct *);
void aoecmd_cleanslate(struct aoedev *);
void aoecmd_exit(void);
int aoecmd_init(void);
struct sk_buff *aoecmd_ata_id(struct aoedev *);
void aoe_freetframe(struct frame *);
int aoedev_init(void);
void aoedev_exit(void);
struct aoedev *aoedev_by_aoeaddr(int maj, int min);
struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
void aoedev_downdev(struct aoedev *d);
int aoedev_flush(const char __user *str, size_t size);
void aoe_failbuf(struct aoedev *d, struct buf *buf);
int aoenet_init(void);
void aoenet_exit(void);
void aoenet_xmit(struct sk_buff_head *);
int is_aoe_netif(struct net_device *ifp);
int set_aoe_iflist(const char __user *str, size_t size);