linux/fs/nfs/internal.h
Weston Andros Adamson 324d003b0c NFS: add nfs_sb_deactive_async to avoid deadlock
Use nfs_sb_deactive_async instead of nfs_sb_deactive when in a workqueue
context.  This avoids a deadlock where rpc_shutdown_client loops forever
in a workqueue kworker context, trying to kill all RPC tasks associated with
the client, while one or more of these tasks have already been assigned to the
same kworker (and will never run rpc_exit_task).

This approach is needed because RPC tasks that have already been assigned
to a kworker by queue_work cannot be canceled, as explained in the comment
for workqueue.c:insert_wq_barrier.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
[Trond: add module_get/put.]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-31 16:26:26 -04:00

610 lines
20 KiB
C

/*
* NFS internal definitions
*/
#include "nfs4_fs.h"
#include <linux/mount.h>
#include <linux/security.h>
#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
struct nfs_string;
/* Maximum number of readahead requests
* FIXME: this should really be a sysctl so that users may tune it to suit
* their needs. People that do NFS over a slow network, might for
* instance want to reduce it to something closer to 1 for improved
* interactive response.
*/
#define NFS_MAX_READAHEAD (RPC_DEF_SLOT_TABLE - 1)
/*
* Determine if sessions are in use.
*/
static inline int nfs4_has_session(const struct nfs_client *clp)
{
#ifdef CONFIG_NFS_V4_1
if (clp->cl_session)
return 1;
#endif /* CONFIG_NFS_V4_1 */
return 0;
}
static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
{
#ifdef CONFIG_NFS_V4_1
if (nfs4_has_session(clp))
return (clp->cl_session->flags & SESSION4_PERSIST);
#endif /* CONFIG_NFS_V4_1 */
return 0;
}
static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
{
if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
}
static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
{
if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
(((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
return 0;
fattr->fileid = fattr->mounted_on_fileid;
return 1;
}
struct nfs_clone_mount {
const struct super_block *sb;
const struct dentry *dentry;
struct nfs_fh *fh;
struct nfs_fattr *fattr;
char *hostname;
char *mnt_path;
struct sockaddr *addr;
size_t addrlen;
rpc_authflavor_t authflavor;
};
/*
* Note: RFC 1813 doesn't limit the number of auth flavors that
* a server can return, so make something up.
*/
#define NFS_MAX_SECFLAVORS (12)
/*
* Value used if the user did not specify a port value.
*/
#define NFS_UNSPEC_PORT (-1)
/*
* Maximum number of pages that readdir can use for creating
* a vmapped array of pages.
*/
#define NFS_MAX_READDIR_PAGES 8
struct nfs_client_initdata {
unsigned long init_flags;
const char *hostname;
const struct sockaddr *addr;
size_t addrlen;
struct nfs_subversion *nfs_mod;
int proto;
u32 minorversion;
struct net *net;
};
/*
* In-kernel mount arguments
*/
struct nfs_parsed_mount_data {
int flags;
unsigned int rsize, wsize;
unsigned int timeo, retrans;
unsigned int acregmin, acregmax,
acdirmin, acdirmax;
unsigned int namlen;
unsigned int options;
unsigned int bsize;
unsigned int auth_flavor_len;
rpc_authflavor_t auth_flavors[1];
char *client_address;
unsigned int version;
unsigned int minorversion;
char *fscache_uniq;
bool need_mount;
struct {
struct sockaddr_storage address;
size_t addrlen;
char *hostname;
u32 version;
int port;
unsigned short protocol;
} mount_server;
struct {
struct sockaddr_storage address;
size_t addrlen;
char *hostname;
char *export_path;
int port;
unsigned short protocol;
} nfs_server;
struct security_mnt_opts lsm_opts;
struct net *net;
};
/* mount_clnt.c */
struct nfs_mount_request {
struct sockaddr *sap;
size_t salen;
char *hostname;
char *dirpath;
u32 version;
unsigned short protocol;
struct nfs_fh *fh;
int noresvport;
unsigned int *auth_flav_len;
rpc_authflavor_t *auth_flavs;
struct net *net;
};
struct nfs_mount_info {
void (*fill_super)(struct super_block *, struct nfs_mount_info *);
int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
struct nfs_parsed_mount_data *parsed;
struct nfs_clone_mount *cloned;
struct nfs_fh *mntfh;
};
extern int nfs_mount(struct nfs_mount_request *info);
extern void nfs_umount(const struct nfs_mount_request *info);
/* client.c */
extern const struct rpc_program nfs_program;
extern void nfs_clients_init(struct net *net);
extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
int nfs_create_rpc_client(struct nfs_client *, const struct rpc_timeout *, rpc_authflavor_t);
struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
const struct rpc_timeout *, const char *,
rpc_authflavor_t);
int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
void nfs_server_insert_lists(struct nfs_server *);
void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
rpc_authflavor_t);
struct nfs_server *nfs_alloc_server(void);
void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
extern void nfs_cleanup_cb_ident_idr(struct net *);
extern void nfs_put_client(struct nfs_client *);
extern void nfs_free_client(struct nfs_client *);
extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
extern struct nfs_client *
nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
struct nfs4_sessionid *);
extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
struct nfs_subversion *);
extern struct nfs_server *nfs4_create_server(
struct nfs_mount_info *,
struct nfs_subversion *);
extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
struct nfs_fh *);
extern void nfs_free_server(struct nfs_server *server);
extern struct nfs_server *nfs_clone_server(struct nfs_server *,
struct nfs_fh *,
struct nfs_fattr *,
rpc_authflavor_t);
extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
const struct sockaddr *ds_addr,
int ds_addrlen, int ds_proto,
unsigned int ds_timeo,
unsigned int ds_retrans);
#ifdef CONFIG_PROC_FS
extern int __init nfs_fs_proc_init(void);
extern void nfs_fs_proc_exit(void);
#else
static inline int nfs_fs_proc_init(void)
{
return 0;
}
static inline void nfs_fs_proc_exit(void)
{
}
#endif
#ifdef CONFIG_NFS_V4_1
int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *);
#endif
/* nfs3client.c */
#if IS_ENABLED(CONFIG_NFS_V3)
struct nfs_server *nfs3_create_server(struct nfs_mount_info *, struct nfs_subversion *);
struct nfs_server *nfs3_clone_server(struct nfs_server *, struct nfs_fh *,
struct nfs_fattr *, rpc_authflavor_t);
#endif
/* callback_xdr.c */
extern struct svc_version nfs4_callback_version1;
extern struct svc_version nfs4_callback_version4;
struct nfs_pageio_descriptor;
/* pagelist.c */
extern int __init nfs_init_nfspagecache(void);
extern void nfs_destroy_nfspagecache(void);
extern int __init nfs_init_readpagecache(void);
extern void nfs_destroy_readpagecache(void);
extern int __init nfs_init_writepagecache(void);
extern void nfs_destroy_writepagecache(void);
extern int __init nfs_init_directcache(void);
extern void nfs_destroy_directcache(void);
extern bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount);
extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr,
void (*release)(struct nfs_pgio_header *hdr));
void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
/* nfs2xdr.c */
extern struct rpc_procinfo nfs_procedures[];
extern int nfs2_decode_dirent(struct xdr_stream *,
struct nfs_entry *, int);
/* nfs3xdr.c */
extern struct rpc_procinfo nfs3_procedures[];
extern int nfs3_decode_dirent(struct xdr_stream *,
struct nfs_entry *, int);
/* nfs4xdr.c */
#if IS_ENABLED(CONFIG_NFS_V4)
extern int nfs4_decode_dirent(struct xdr_stream *,
struct nfs_entry *, int);
#endif
#ifdef CONFIG_NFS_V4_1
extern const u32 nfs41_maxread_overhead;
extern const u32 nfs41_maxwrite_overhead;
#endif
/* nfs4proc.c */
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct rpc_procinfo nfs4_procedures[];
#endif
extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);
/* proc.c */
void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
const struct rpc_timeout *timeparms,
const char *ip_addr, rpc_authflavor_t authflavour);
/* dir.c */
extern int nfs_access_cache_shrinker(struct shrinker *shrink,
struct shrink_control *sc);
struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
int nfs_create(struct inode *, struct dentry *, umode_t, bool);
int nfs_mkdir(struct inode *, struct dentry *, umode_t);
int nfs_rmdir(struct inode *, struct dentry *);
int nfs_unlink(struct inode *, struct dentry *);
int nfs_symlink(struct inode *, struct dentry *, const char *);
int nfs_link(struct dentry *, struct inode *, struct dentry *);
int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
/* file.c */
int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int);
loff_t nfs_file_llseek(struct file *, loff_t, int);
int nfs_file_flush(struct file *, fl_owner_t);
ssize_t nfs_file_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
size_t, unsigned int);
int nfs_file_mmap(struct file *, struct vm_area_struct *);
ssize_t nfs_file_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
int nfs_file_release(struct inode *, struct file *);
int nfs_lock(struct file *, int, struct file_lock *);
int nfs_flock(struct file *, int, struct file_lock *);
ssize_t nfs_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *,
size_t, unsigned int);
int nfs_check_flags(int);
int nfs_setlease(struct file *, long, struct file_lock **);
/* inode.c */
extern struct workqueue_struct *nfsiod_workqueue;
extern struct inode *nfs_alloc_inode(struct super_block *sb);
extern void nfs_destroy_inode(struct inode *);
extern int nfs_write_inode(struct inode *, struct writeback_control *);
extern void nfs_clear_inode(struct inode *);
extern void nfs_evict_inode(struct inode *);
void nfs_zap_acl_cache(struct inode *inode);
extern int nfs_wait_bit_killable(void *word);
/* super.c */
extern const struct super_operations nfs_sops;
extern struct file_system_type nfs_fs_type;
extern struct file_system_type nfs_xdev_fs_type;
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct file_system_type nfs4_xdev_fs_type;
extern struct file_system_type nfs4_referral_fs_type;
#endif
struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
struct nfs_subversion *);
void nfs_initialise_sb(struct super_block *);
int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
struct nfs_mount_info *, struct nfs_subversion *);
struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
const char *, struct nfs_mount_info *);
void nfs_kill_super(struct super_block *);
void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
extern struct rpc_stat nfs_rpcstat;
extern int __init register_nfs_fs(void);
extern void __exit unregister_nfs_fs(void);
extern void nfs_sb_active(struct super_block *sb);
extern void nfs_sb_deactive(struct super_block *sb);
extern void nfs_sb_deactive_async(struct super_block *sb);
/* namespace.c */
#define NFS_PATH_CANONICAL 1
extern char *nfs_path(char **p, struct dentry *dentry,
char *buffer, ssize_t buflen, unsigned flags);
extern struct vfsmount *nfs_d_automount(struct path *path);
struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
struct nfs_fh *, struct nfs_fattr *);
struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
struct nfs_fattr *, rpc_authflavor_t);
/* getroot.c */
extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
const char *);
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
const char *);
extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);
#endif
struct nfs_pgio_completion_ops;
/* read.c */
extern struct nfs_read_header *nfs_readhdr_alloc(void);
extern void nfs_readhdr_free(struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
struct inode *inode,
const struct nfs_pgio_completion_ops *compl_ops);
extern int nfs_initiate_read(struct rpc_clnt *clnt,
struct nfs_read_data *data,
const struct rpc_call_ops *call_ops, int flags);
extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
struct inode *inode,
const struct nfs_pgio_completion_ops *compl_ops);
extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
extern void nfs_readdata_release(struct nfs_read_data *rdata);
/* super.c */
void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
void nfs_umount_begin(struct super_block *);
int nfs_statfs(struct dentry *, struct kstatfs *);
int nfs_show_options(struct seq_file *, struct dentry *);
int nfs_show_devname(struct seq_file *, struct dentry *);
int nfs_show_path(struct seq_file *, struct dentry *);
int nfs_show_stats(struct seq_file *, struct dentry *);
void nfs_put_super(struct super_block *);
int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
/* write.c */
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
struct inode *inode, int ioflags,
const struct nfs_pgio_completion_ops *compl_ops);
extern struct nfs_write_header *nfs_writehdr_alloc(void);
extern void nfs_writehdr_free(struct nfs_pgio_header *hdr);
extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
struct inode *inode, int ioflags,
const struct nfs_pgio_completion_ops *compl_ops);
extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
extern void nfs_writedata_release(struct nfs_write_data *wdata);
extern void nfs_commit_free(struct nfs_commit_data *p);
extern int nfs_initiate_write(struct rpc_clnt *clnt,
struct nfs_write_data *data,
const struct rpc_call_ops *call_ops,
int how, int flags);
extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
extern int nfs_initiate_commit(struct rpc_clnt *clnt,
struct nfs_commit_data *data,
const struct rpc_call_ops *call_ops,
int how, int flags);
extern void nfs_init_commit(struct nfs_commit_data *data,
struct list_head *head,
struct pnfs_layout_segment *lseg,
struct nfs_commit_info *cinfo);
int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
struct nfs_commit_info *cinfo, int max);
int nfs_scan_commit(struct inode *inode, struct list_head *dst,
struct nfs_commit_info *cinfo);
void nfs_mark_request_commit(struct nfs_page *req,
struct pnfs_layout_segment *lseg,
struct nfs_commit_info *cinfo);
int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
int how, struct nfs_commit_info *cinfo);
void nfs_retry_commit(struct list_head *page_list,
struct pnfs_layout_segment *lseg,
struct nfs_commit_info *cinfo);
void nfs_commitdata_release(struct nfs_commit_data *data);
void nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst,
struct nfs_commit_info *cinfo);
void nfs_request_remove_commit_list(struct nfs_page *req,
struct nfs_commit_info *cinfo);
void nfs_init_cinfo(struct nfs_commit_info *cinfo,
struct inode *inode,
struct nfs_direct_req *dreq);
#ifdef CONFIG_MIGRATION
extern int nfs_migrate_page(struct address_space *,
struct page *, struct page *, enum migrate_mode);
#else
#define nfs_migrate_page NULL
#endif
/* direct.c */
void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
struct nfs_direct_req *dreq);
static inline void nfs_inode_dio_wait(struct inode *inode)
{
inode_dio_wait(inode);
}
extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);
/* nfs4proc.c */
extern void __nfs4_read_done_cb(struct nfs_read_data *);
extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
const struct rpc_timeout *timeparms,
const char *ip_addr,
rpc_authflavor_t authflavour);
extern int _nfs4_call_sync(struct rpc_clnt *clnt,
struct nfs_server *server,
struct rpc_message *msg,
struct nfs4_sequence_args *args,
struct nfs4_sequence_res *res,
int cache_reply);
extern int _nfs4_call_sync_session(struct rpc_clnt *clnt,
struct nfs_server *server,
struct rpc_message *msg,
struct nfs4_sequence_args *args,
struct nfs4_sequence_res *res,
int cache_reply);
extern int nfs40_walk_client_list(struct nfs_client *clp,
struct nfs_client **result,
struct rpc_cred *cred);
extern int nfs41_walk_client_list(struct nfs_client *clp,
struct nfs_client **result,
struct rpc_cred *cred);
/*
* Determine the device name as a string
*/
static inline char *nfs_devname(struct dentry *dentry,
char *buffer, ssize_t buflen)
{
char *dummy;
return nfs_path(&dummy, dentry, buffer, buflen, NFS_PATH_CANONICAL);
}
/*
* Determine the actual block size (and log2 thereof)
*/
static inline
unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
{
/* make sure blocksize is a power of two */
if ((bsize & (bsize - 1)) || nrbitsp) {
unsigned char nrbits;
for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
;
bsize = 1 << nrbits;
if (nrbitsp)
*nrbitsp = nrbits;
}
return bsize;
}
/*
* Calculate the number of 512byte blocks used.
*/
static inline blkcnt_t nfs_calc_block_size(u64 tsize)
{
blkcnt_t used = (tsize + 511) >> 9;
return (used > ULONG_MAX) ? ULONG_MAX : used;
}
/*
* Compute and set NFS server blocksize
*/
static inline
unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
{
if (bsize < NFS_MIN_FILE_IO_SIZE)
bsize = NFS_DEF_FILE_IO_SIZE;
else if (bsize >= NFS_MAX_FILE_IO_SIZE)
bsize = NFS_MAX_FILE_IO_SIZE;
return nfs_block_bits(bsize, nrbitsp);
}
/*
* Determine the maximum file size for a superblock
*/
static inline
void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
{
sb->s_maxbytes = (loff_t)maxfilesize;
if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
sb->s_maxbytes = MAX_LFS_FILESIZE;
}
/*
* Determine the number of bytes of data the page contains
*/
static inline
unsigned int nfs_page_length(struct page *page)
{
loff_t i_size = i_size_read(page_file_mapping(page)->host);
if (i_size > 0) {
pgoff_t page_index = page_file_index(page);
pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
if (page_index < end_index)
return PAGE_CACHE_SIZE;
if (page_index == end_index)
return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
}
return 0;
}
/*
* Convert a umode to a dirent->d_type
*/
static inline
unsigned char nfs_umode_to_dtype(umode_t mode)
{
return (mode >> 12) & 15;
}
/*
* Determine the number of pages in an array of length 'len' and
* with a base offset of 'base'
*/
static inline
unsigned int nfs_page_array_len(unsigned int base, size_t len)
{
return ((unsigned long)len + (unsigned long)base +
PAGE_SIZE - 1) >> PAGE_SHIFT;
}
/*
* Convert a struct timespec into a 64-bit change attribute
*
* This does approximately the same thing as timespec_to_ns(),
* but for calculation efficiency, we multiply the seconds by
* 1024*1024*1024.
*/
static inline
u64 nfs_timespec_to_change_attr(const struct timespec *ts)
{
return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
}