linux-sg2042/fs/nfs/blocklayout/blocklayout.h

212 lines
7.4 KiB
C

/*
* linux/fs/nfs/blocklayout/blocklayout.h
*
* Module for the NFSv4.1 pNFS block layout driver.
*
* Copyright (c) 2006 The Regents of the University of Michigan.
* All rights reserved.
*
* Andy Adamson <andros@citi.umich.edu>
* Fred Isaman <iisaman@umich.edu>
*
* permission is granted to use, copy, create derivative works and
* redistribute this software and such derivative works for any purpose,
* so long as the name of the university of michigan is not used in
* any advertising or publicity pertaining to the use or distribution
* of this software without specific, written prior authorization. if
* the above copyright notice or any other identification of the
* university of michigan is included in any copy of any portion of
* this software, then the disclaimer below must also be included.
*
* this software is provided as is, without representation from the
* university of michigan as to its fitness for any purpose, and without
* warranty by the university of michigan of any kind, either express
* or implied, including without limitation the implied warranties of
* merchantability and fitness for a particular purpose. the regents
* of the university of michigan shall not be liable for any damages,
* including special, indirect, incidental, or consequential damages,
* with respect to any claim arising out or in connection with the use
* of the software, even if it has been or is hereafter advised of the
* possibility of such damages.
*/
#ifndef FS_NFS_NFS4BLOCKLAYOUT_H
#define FS_NFS_NFS4BLOCKLAYOUT_H
#include <linux/device-mapper.h>
#include <linux/nfs_fs.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include "../nfs4_fs.h"
#include "../pnfs.h"
#include "../netns.h"
#define PAGE_CACHE_SECTORS (PAGE_CACHE_SIZE >> SECTOR_SHIFT)
#define PAGE_CACHE_SECTOR_SHIFT (PAGE_CACHE_SHIFT - SECTOR_SHIFT)
#define SECTOR_SIZE (1 << SECTOR_SHIFT)
struct block_mount_id {
spinlock_t bm_lock; /* protects list */
struct list_head bm_devlist; /* holds pnfs_block_dev */
};
struct pnfs_block_dev {
struct list_head bm_node;
struct nfs4_deviceid bm_mdevid; /* associated devid */
struct block_device *bm_mdev; /* meta device itself */
struct net *net;
};
enum exstate4 {
PNFS_BLOCK_READWRITE_DATA = 0,
PNFS_BLOCK_READ_DATA = 1,
PNFS_BLOCK_INVALID_DATA = 2, /* mapped, but data is invalid */
PNFS_BLOCK_NONE_DATA = 3 /* unmapped, it's a hole */
};
#define MY_MAX_TAGS (15) /* tag bitnums used must be less than this */
struct my_tree {
sector_t mtt_step_size; /* Internal sector alignment */
struct list_head mtt_stub; /* Should be a radix tree */
};
struct pnfs_inval_markings {
spinlock_t im_lock;
struct my_tree im_tree; /* Sectors that need LAYOUTCOMMIT */
sector_t im_block_size; /* Server blocksize in sectors */
struct list_head im_extents; /* Short extents for INVAL->RW conversion */
};
struct pnfs_inval_tracking {
struct list_head it_link;
int it_sector;
int it_tags;
};
/* sector_t fields are all in 512-byte sectors */
struct pnfs_block_extent {
struct kref be_refcnt;
struct list_head be_node; /* link into lseg list */
struct nfs4_deviceid be_devid; /* FIXME: could use device cache instead */
struct block_device *be_mdev;
sector_t be_f_offset; /* the starting offset in the file */
sector_t be_length; /* the size of the extent */
sector_t be_v_offset; /* the starting offset in the volume */
enum exstate4 be_state; /* the state of this extent */
struct pnfs_inval_markings *be_inval; /* tracks INVAL->RW transition */
};
/* Shortened extent used by LAYOUTCOMMIT */
struct pnfs_block_short_extent {
struct list_head bse_node;
struct nfs4_deviceid bse_devid;
struct block_device *bse_mdev;
sector_t bse_f_offset; /* the starting offset in the file */
sector_t bse_length; /* the size of the extent */
};
static inline void
BL_INIT_INVAL_MARKS(struct pnfs_inval_markings *marks, sector_t blocksize)
{
spin_lock_init(&marks->im_lock);
INIT_LIST_HEAD(&marks->im_tree.mtt_stub);
INIT_LIST_HEAD(&marks->im_extents);
marks->im_block_size = blocksize;
marks->im_tree.mtt_step_size = min((sector_t)PAGE_CACHE_SECTORS,
blocksize);
}
enum extentclass4 {
RW_EXTENT = 0, /* READWRTE and INVAL */
RO_EXTENT = 1, /* READ and NONE */
EXTENT_LISTS = 2,
};
static inline int bl_choose_list(enum exstate4 state)
{
if (state == PNFS_BLOCK_READ_DATA || state == PNFS_BLOCK_NONE_DATA)
return RO_EXTENT;
else
return RW_EXTENT;
}
struct pnfs_block_layout {
struct pnfs_layout_hdr bl_layout;
struct pnfs_inval_markings bl_inval; /* tracks INVAL->RW transition */
spinlock_t bl_ext_lock; /* Protects list manipulation */
struct list_head bl_extents[EXTENT_LISTS]; /* R and RW extents */
struct list_head bl_commit; /* Needs layout commit */
struct list_head bl_committing; /* Layout committing */
unsigned int bl_count; /* entries in bl_commit */
sector_t bl_blocksize; /* Server blocksize in sectors */
};
#define BLK_ID(lo) ((struct block_mount_id *)(NFS_SERVER(lo->plh_inode)->pnfs_ld_data))
static inline struct pnfs_block_layout *
BLK_LO2EXT(struct pnfs_layout_hdr *lo)
{
return container_of(lo, struct pnfs_block_layout, bl_layout);
}
static inline struct pnfs_block_layout *
BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
{
return BLK_LO2EXT(lseg->pls_layout);
}
struct bl_pipe_msg {
struct rpc_pipe_msg msg;
wait_queue_head_t *bl_wq;
};
struct bl_msg_hdr {
u8 type;
u16 totallen; /* length of entire message, including hdr itself */
};
#define BL_DEVICE_UMOUNT 0x0 /* Umount--delete devices */
#define BL_DEVICE_MOUNT 0x1 /* Mount--create devices*/
#define BL_DEVICE_REQUEST_INIT 0x0 /* Start request */
#define BL_DEVICE_REQUEST_PROC 0x1 /* User level process succeeds */
#define BL_DEVICE_REQUEST_ERR 0x2 /* User level process fails */
/* blocklayoutdev.c */
ssize_t bl_pipe_downcall(struct file *, const char __user *, size_t);
void bl_pipe_destroy_msg(struct rpc_pipe_msg *);
void nfs4_blkdev_put(struct block_device *bdev);
struct pnfs_block_dev *nfs4_blk_decode_device(struct nfs_server *server,
struct pnfs_device *dev);
int nfs4_blk_process_layoutget(struct pnfs_layout_hdr *lo,
struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
/* blocklayoutdm.c */
void bl_free_block_dev(struct pnfs_block_dev *bdev);
/* extents.c */
struct pnfs_block_extent *
bl_find_get_extent(struct pnfs_block_layout *bl, sector_t isect,
struct pnfs_block_extent **cow_read);
int bl_mark_sectors_init(struct pnfs_inval_markings *marks,
sector_t offset, sector_t length);
void bl_put_extent(struct pnfs_block_extent *be);
struct pnfs_block_extent *bl_alloc_extent(void);
int bl_is_sector_init(struct pnfs_inval_markings *marks, sector_t isect);
int encode_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
struct xdr_stream *xdr,
const struct nfs4_layoutcommit_args *arg);
void clean_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
const struct nfs4_layoutcommit_args *arg,
int status);
int bl_add_merge_extent(struct pnfs_block_layout *bl,
struct pnfs_block_extent *new);
int bl_mark_for_commit(struct pnfs_block_extent *be,
sector_t offset, sector_t length,
struct pnfs_block_short_extent *new);
int bl_push_one_short_extent(struct pnfs_inval_markings *marks);
struct pnfs_block_short_extent *
bl_pop_one_short_extent(struct pnfs_inval_markings *marks);
void bl_free_short_extents(struct pnfs_inval_markings *marks, int num_to_free);
#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */