cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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nfs_page.h (6912B)


      1/* SPDX-License-Identifier: GPL-2.0 */
      2/*
      3 * linux/include/linux/nfs_page.h
      4 *
      5 * Copyright (C) 2000 Trond Myklebust
      6 *
      7 * NFS page cache wrapper.
      8 */
      9
     10#ifndef _LINUX_NFS_PAGE_H
     11#define _LINUX_NFS_PAGE_H
     12
     13
     14#include <linux/list.h>
     15#include <linux/pagemap.h>
     16#include <linux/wait.h>
     17#include <linux/sunrpc/auth.h>
     18#include <linux/nfs_xdr.h>
     19
     20#include <linux/kref.h>
     21
     22/*
     23 * Valid flags for a dirty buffer
     24 */
     25enum {
     26	PG_BUSY = 0,		/* nfs_{un}lock_request */
     27	PG_MAPPED,		/* page private set for buffered io */
     28	PG_CLEAN,		/* write succeeded */
     29	PG_COMMIT_TO_DS,	/* used by pnfs layouts */
     30	PG_INODE_REF,		/* extra ref held by inode when in writeback */
     31	PG_HEADLOCK,		/* page group lock of wb_head */
     32	PG_TEARDOWN,		/* page group sync for destroy */
     33	PG_UNLOCKPAGE,		/* page group sync bit in read path */
     34	PG_UPTODATE,		/* page group sync bit in read path */
     35	PG_WB_END,		/* page group sync bit in write path */
     36	PG_REMOVE,		/* page group sync bit in write path */
     37	PG_CONTENDED1,		/* Is someone waiting for a lock? */
     38	PG_CONTENDED2,		/* Is someone waiting for a lock? */
     39};
     40
     41struct nfs_inode;
     42struct nfs_page {
     43	struct list_head	wb_list;	/* Defines state of page: */
     44	struct page		*wb_page;	/* page to read in/write out */
     45	struct nfs_lock_context	*wb_lock_context;	/* lock context info */
     46	pgoff_t			wb_index;	/* Offset >> PAGE_SHIFT */
     47	unsigned int		wb_offset,	/* Offset & ~PAGE_MASK */
     48				wb_pgbase,	/* Start of page data */
     49				wb_bytes;	/* Length of request */
     50	struct kref		wb_kref;	/* reference count */
     51	unsigned long		wb_flags;
     52	struct nfs_write_verifier	wb_verf;	/* Commit cookie */
     53	struct nfs_page		*wb_this_page;  /* list of reqs for this page */
     54	struct nfs_page		*wb_head;       /* head pointer for req list */
     55	unsigned short		wb_nio;		/* Number of I/O attempts */
     56};
     57
     58struct nfs_pgio_mirror;
     59struct nfs_pageio_descriptor;
     60struct nfs_pageio_ops {
     61	void	(*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *);
     62	size_t	(*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *,
     63			   struct nfs_page *);
     64	int	(*pg_doio)(struct nfs_pageio_descriptor *);
     65	unsigned int	(*pg_get_mirror_count)(struct nfs_pageio_descriptor *,
     66				       struct nfs_page *);
     67	void	(*pg_cleanup)(struct nfs_pageio_descriptor *);
     68	struct nfs_pgio_mirror *
     69		(*pg_get_mirror)(struct nfs_pageio_descriptor *, u32);
     70	u32	(*pg_set_mirror)(struct nfs_pageio_descriptor *, u32);
     71};
     72
     73struct nfs_rw_ops {
     74	struct nfs_pgio_header *(*rw_alloc_header)(void);
     75	void (*rw_free_header)(struct nfs_pgio_header *);
     76	int  (*rw_done)(struct rpc_task *, struct nfs_pgio_header *,
     77			struct inode *);
     78	void (*rw_result)(struct rpc_task *, struct nfs_pgio_header *);
     79	void (*rw_initiate)(struct nfs_pgio_header *, struct rpc_message *,
     80			    const struct nfs_rpc_ops *,
     81			    struct rpc_task_setup *, int);
     82};
     83
     84struct nfs_pgio_mirror {
     85	struct list_head	pg_list;
     86	unsigned long		pg_bytes_written;
     87	size_t			pg_count;
     88	size_t			pg_bsize;
     89	unsigned int		pg_base;
     90	unsigned char		pg_recoalesce : 1;
     91};
     92
     93struct nfs_pageio_descriptor {
     94	struct inode		*pg_inode;
     95	const struct nfs_pageio_ops *pg_ops;
     96	const struct nfs_rw_ops *pg_rw_ops;
     97	int 			pg_ioflags;
     98	int			pg_error;
     99	const struct rpc_call_ops *pg_rpc_callops;
    100	const struct nfs_pgio_completion_ops *pg_completion_ops;
    101	struct pnfs_layout_segment *pg_lseg;
    102	struct nfs_io_completion *pg_io_completion;
    103	struct nfs_direct_req	*pg_dreq;
    104	unsigned int		pg_bsize;	/* default bsize for mirrors */
    105
    106	u32			pg_mirror_count;
    107	struct nfs_pgio_mirror	*pg_mirrors;
    108	struct nfs_pgio_mirror	pg_mirrors_static[1];
    109	struct nfs_pgio_mirror	*pg_mirrors_dynamic;
    110	u32			pg_mirror_idx;	/* current mirror */
    111	unsigned short		pg_maxretrans;
    112	unsigned char		pg_moreio : 1;
    113};
    114
    115/* arbitrarily selected limit to number of mirrors */
    116#define NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX 16
    117
    118#define NFS_WBACK_BUSY(req)	(test_bit(PG_BUSY,&(req)->wb_flags))
    119
    120extern	struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
    121					    struct page *page,
    122					    unsigned int offset,
    123					    unsigned int count);
    124extern	void nfs_release_request(struct nfs_page *);
    125
    126
    127extern	void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
    128			     struct inode *inode,
    129			     const struct nfs_pageio_ops *pg_ops,
    130			     const struct nfs_pgio_completion_ops *compl_ops,
    131			     const struct nfs_rw_ops *rw_ops,
    132			     size_t bsize,
    133			     int how);
    134extern	int nfs_pageio_add_request(struct nfs_pageio_descriptor *,
    135				   struct nfs_page *);
    136extern  int nfs_pageio_resend(struct nfs_pageio_descriptor *,
    137			      struct nfs_pgio_header *);
    138extern	void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
    139extern	void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
    140extern size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
    141				struct nfs_page *prev,
    142				struct nfs_page *req);
    143extern  int nfs_wait_on_request(struct nfs_page *);
    144extern	void nfs_unlock_request(struct nfs_page *req);
    145extern	void nfs_unlock_and_release_request(struct nfs_page *);
    146extern	struct nfs_page *nfs_page_group_lock_head(struct nfs_page *req);
    147extern	int nfs_page_group_lock_subrequests(struct nfs_page *head);
    148extern	void nfs_join_page_group(struct nfs_page *head, struct inode *inode);
    149extern int nfs_page_group_lock(struct nfs_page *);
    150extern void nfs_page_group_unlock(struct nfs_page *);
    151extern bool nfs_page_group_sync_on_bit(struct nfs_page *, unsigned int);
    152extern	int nfs_page_set_headlock(struct nfs_page *req);
    153extern void nfs_page_clear_headlock(struct nfs_page *req);
    154extern bool nfs_async_iocounter_wait(struct rpc_task *, struct nfs_lock_context *);
    155
    156/*
    157 * Lock the page of an asynchronous request
    158 */
    159static inline int
    160nfs_lock_request(struct nfs_page *req)
    161{
    162	return !test_and_set_bit(PG_BUSY, &req->wb_flags);
    163}
    164
    165/**
    166 * nfs_list_add_request - Insert a request into a list
    167 * @req: request
    168 * @head: head of list into which to insert the request.
    169 */
    170static inline void
    171nfs_list_add_request(struct nfs_page *req, struct list_head *head)
    172{
    173	list_add_tail(&req->wb_list, head);
    174}
    175
    176/**
    177 * nfs_list_move_request - Move a request to a new list
    178 * @req: request
    179 * @head: head of list into which to insert the request.
    180 */
    181static inline void
    182nfs_list_move_request(struct nfs_page *req, struct list_head *head)
    183{
    184	list_move_tail(&req->wb_list, head);
    185}
    186
    187/**
    188 * nfs_list_remove_request - Remove a request from its wb_list
    189 * @req: request
    190 */
    191static inline void
    192nfs_list_remove_request(struct nfs_page *req)
    193{
    194	if (list_empty(&req->wb_list))
    195		return;
    196	list_del_init(&req->wb_list);
    197}
    198
    199static inline struct nfs_page *
    200nfs_list_entry(struct list_head *head)
    201{
    202	return list_entry(head, struct nfs_page, wb_list);
    203}
    204
    205static inline
    206loff_t req_offset(struct nfs_page *req)
    207{
    208	return (((loff_t)req->wb_index) << PAGE_SHIFT) + req->wb_offset;
    209}
    210
    211static inline struct nfs_open_context *
    212nfs_req_openctx(struct nfs_page *req)
    213{
    214	return req->wb_lock_context->open_context;
    215}
    216
    217#endif /* _LINUX_NFS_PAGE_H */