remarkable-linux/fs/nfs/filelayout/filelayout.h
Peng Tao 39280a5ae8 nfs41: move file layout macros to generic pnfs
They can be reused by flexfile layout as well.

Also add a code such that if read fails on one DS and
there are other DSes available to use, don't resend
through MDS but through pNFS so that client can read
from other DSes.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:33 -08:00

118 lines
3.7 KiB
C

/*
* NFSv4 file layout driver data structures.
*
* Copyright (c) 2002
* The Regents of the University of Michigan
* All Rights Reserved
*
* Dean Hildebrand <dhildebz@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 or warranty
* of any kind either express or implied, including without limitation
* the implied warranties of merchantability, fitness for a particular
* purpose, or noninfringement. 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 of 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_NFS4FILELAYOUT_H
#define FS_NFS_NFS4FILELAYOUT_H
#include "../pnfs.h"
/*
* Field testing shows we need to support up to 4096 stripe indices.
* We store each index as a u8 (u32 on the wire) to keep the memory footprint
* reasonable. This in turn means we support a maximum of 256
* RFC 5661 multipath_list4 structures.
*/
#define NFS4_PNFS_MAX_STRIPE_CNT 4096
#define NFS4_PNFS_MAX_MULTI_CNT 256 /* 256 fit into a u8 stripe_index */
enum stripetype4 {
STRIPE_SPARSE = 1,
STRIPE_DENSE = 2
};
struct nfs4_file_layout_dsaddr {
struct nfs4_deviceid_node id_node;
u32 stripe_count;
u8 *stripe_indices;
u32 ds_num;
struct nfs4_pnfs_ds *ds_list[1];
};
struct nfs4_filelayout_segment {
struct pnfs_layout_segment generic_hdr;
u32 stripe_type;
u32 commit_through_mds;
u32 stripe_unit;
u32 first_stripe_index;
u64 pattern_offset;
struct nfs4_file_layout_dsaddr *dsaddr; /* Point to GETDEVINFO data */
unsigned int num_fh;
struct nfs_fh **fh_array;
};
struct nfs4_filelayout {
struct pnfs_layout_hdr generic_hdr;
struct pnfs_ds_commit_info commit_info;
};
static inline struct nfs4_filelayout *
FILELAYOUT_FROM_HDR(struct pnfs_layout_hdr *lo)
{
return container_of(lo, struct nfs4_filelayout, generic_hdr);
}
static inline struct nfs4_filelayout_segment *
FILELAYOUT_LSEG(struct pnfs_layout_segment *lseg)
{
return container_of(lseg,
struct nfs4_filelayout_segment,
generic_hdr);
}
static inline struct nfs4_deviceid_node *
FILELAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg)
{
return &FILELAYOUT_LSEG(lseg)->dsaddr->id_node;
}
static inline bool
filelayout_test_devid_invalid(struct nfs4_deviceid_node *node)
{
return test_bit(NFS_DEVICEID_INVALID, &node->flags);
}
extern bool
filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node);
extern struct nfs_fh *
nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j);
u32 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset);
u32 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j);
struct nfs4_pnfs_ds *nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg,
u32 ds_idx);
extern struct nfs4_file_layout_dsaddr *
nfs4_fl_alloc_deviceid_node(struct nfs_server *server,
struct pnfs_device *pdev, gfp_t gfp_flags);
extern void nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
extern void nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
#endif /* FS_NFS_NFS4FILELAYOUT_H */