Linux kernel mirror (for testing)
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linux
1#ifndef __SHMEM_FS_H
2#define __SHMEM_FS_H
3
4#include <linux/swap.h>
5#include <linux/mempolicy.h>
6#include <linux/pagemap.h>
7#include <linux/percpu_counter.h>
8
9/* inode in-kernel data */
10
11#define SHMEM_NR_DIRECT 16
12
13#define SHMEM_SYMLINK_INLINE_LEN (SHMEM_NR_DIRECT * sizeof(swp_entry_t))
14
15struct shmem_inode_info {
16 spinlock_t lock;
17 unsigned long flags;
18 unsigned long alloced; /* data pages alloced to file */
19 unsigned long swapped; /* subtotal assigned to swap */
20 unsigned long next_index; /* highest alloced index + 1 */
21 struct shared_policy policy; /* NUMA memory alloc policy */
22 struct page *i_indirect; /* top indirect blocks page */
23 union {
24 swp_entry_t i_direct[SHMEM_NR_DIRECT]; /* first blocks */
25 char inline_symlink[SHMEM_SYMLINK_INLINE_LEN];
26 };
27 struct list_head swaplist; /* chain of maybes on swap */
28 struct list_head xattr_list; /* list of shmem_xattr */
29 struct inode vfs_inode;
30};
31
32struct shmem_sb_info {
33 unsigned long max_blocks; /* How many blocks are allowed */
34 struct percpu_counter used_blocks; /* How many are allocated */
35 unsigned long max_inodes; /* How many inodes are allowed */
36 unsigned long free_inodes; /* How many are left for allocation */
37 spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
38 uid_t uid; /* Mount uid for root directory */
39 gid_t gid; /* Mount gid for root directory */
40 mode_t mode; /* Mount mode for root directory */
41 struct mempolicy *mpol; /* default memory policy for mappings */
42};
43
44static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
45{
46 return container_of(inode, struct shmem_inode_info, vfs_inode);
47}
48
49/*
50 * Functions in mm/shmem.c called directly from elsewhere:
51 */
52extern int init_tmpfs(void);
53extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
54extern struct file *shmem_file_setup(const char *name,
55 loff_t size, unsigned long flags);
56extern int shmem_zero_setup(struct vm_area_struct *);
57extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
58extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
59 pgoff_t index, gfp_t gfp_mask);
60extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
61extern int shmem_unuse(swp_entry_t entry, struct page *page);
62extern void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
63 struct page **pagep, swp_entry_t *ent);
64
65static inline struct page *shmem_read_mapping_page(
66 struct address_space *mapping, pgoff_t index)
67{
68 return shmem_read_mapping_page_gfp(mapping, index,
69 mapping_gfp_mask(mapping));
70}
71
72#endif