linux-hardened/fs/nfs/nfs4filelayout.h
Andy Adamson c23266d532 NFS4.1 Fix data server connection race
Unlike meta data server mounts which support multiple mount points to
the same server via struct nfs_server, data servers support a single connection.

Concurrent calls to setup the data server connection can race where the first
call allocates the nfs_client struct, and before the cache struct nfs_client
pointer can be set, a second call also tries to setup the connection, finds the
already allocated nfs_client, bumps the reference count, re-initializes the
session,etc. This results in a hanging data server session after umount.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-05-08 17:19:32 -04:00

155 lines
4.8 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"
/*
* Default data server connection timeout and retrans vaules.
* Set by module paramters dataserver_timeo and dataserver_retrans.
*/
#define NFS4_DEF_DS_TIMEO 600 /* in tenths of a second */
#define NFS4_DEF_DS_RETRANS 5
/*
* 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 */
/* error codes for internal use */
#define NFS4ERR_RESET_TO_MDS 12001
enum stripetype4 {
STRIPE_SPARSE = 1,
STRIPE_DENSE = 2
};
/* Individual ip address */
struct nfs4_pnfs_ds_addr {
struct sockaddr_storage da_addr;
size_t da_addrlen;
struct list_head da_node; /* nfs4_pnfs_dev_hlist dev_dslist */
char *da_remotestr; /* human readable addr+port */
};
struct nfs4_pnfs_ds {
struct list_head ds_node; /* nfs4_pnfs_dev_hlist dev_dslist */
char *ds_remotestr; /* comma sep list of addrs */
struct list_head ds_addrs;
struct nfs_client *ds_clp;
atomic_t ds_count;
unsigned long ds_state;
#define NFS4DS_CONNECTING 0 /* ds is establishing connection */
};
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 void
filelayout_mark_devid_invalid(struct nfs4_deviceid_node *node)
{
u32 *p = (u32 *)&node->deviceid;
printk(KERN_WARNING "NFS: Deviceid [%x%x%x%x] marked out of use.\n",
p[0], p[1], p[2], p[3]);
set_bit(NFS_DEVICEID_INVALID, &node->flags);
}
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);
extern void print_ds(struct nfs4_pnfs_ds *ds);
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 void nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
extern void nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
struct nfs4_file_layout_dsaddr *
filelayout_get_device_info(struct inode *inode, struct nfs4_deviceid *dev_id, gfp_t gfp_flags);
#endif /* FS_NFS_NFS4FILELAYOUT_H */