1 #ifndef __SHMEM_FS_H
2 #define __SHMEM_FS_H
3
4 #include <linux/file.h>
5 #include <linux/swap.h>
6 #include <linux/mempolicy.h>
7 #include <linux/pagemap.h>
8 #include <linux/percpu_counter.h>
9 #include <linux/xattr.h>
10
11 /* inode in-kernel data */
12
13 struct shmem_inode_info {
14 spinlock_t lock;
15 unsigned int seals; /* shmem seals */
16 unsigned long flags;
17 unsigned long alloced; /* data pages alloced to file */
18 unsigned long swapped; /* subtotal assigned to swap */
19 struct shared_policy policy; /* NUMA memory alloc policy */
20 struct list_head swaplist; /* chain of maybes on swap */
21 struct simple_xattrs xattrs; /* list of xattrs */
22 struct inode vfs_inode;
23 };
24
25 struct shmem_sb_info {
26 unsigned long max_blocks; /* How many blocks are allowed */
27 struct percpu_counter used_blocks; /* How many are allocated */
28 unsigned long max_inodes; /* How many inodes are allowed */
29 unsigned long free_inodes; /* How many are left for allocation */
30 spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
31 kuid_t uid; /* Mount uid for root directory */
32 kgid_t gid; /* Mount gid for root directory */
33 umode_t mode; /* Mount mode for root directory */
34 struct mempolicy *mpol; /* default memory policy for mappings */
35 };
36
SHMEM_I(struct inode * inode)37 static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
38 {
39 return container_of(inode, struct shmem_inode_info, vfs_inode);
40 }
41
42 /*
43 * Functions in mm/shmem.c called directly from elsewhere:
44 */
45 extern int shmem_init(void);
46 extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
47 extern struct file *shmem_file_setup(const char *name,
48 loff_t size, unsigned long flags);
49 extern struct file *shmem_kernel_file_setup(const char *name, loff_t size,
50 unsigned long flags);
51 extern int shmem_zero_setup(struct vm_area_struct *);
52 extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
53 extern bool shmem_mapping(struct address_space *mapping);
54 extern void shmem_unlock_mapping(struct address_space *mapping);
55 extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
56 pgoff_t index, gfp_t gfp_mask);
57 extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
58 extern int shmem_unuse(swp_entry_t entry, struct page *page);
59
shmem_read_mapping_page(struct address_space * mapping,pgoff_t index)60 static inline struct page *shmem_read_mapping_page(
61 struct address_space *mapping, pgoff_t index)
62 {
63 return shmem_read_mapping_page_gfp(mapping, index,
64 mapping_gfp_mask(mapping));
65 }
66
67 #ifdef CONFIG_TMPFS
68
69 extern int shmem_add_seals(struct file *file, unsigned int seals);
70 extern int shmem_get_seals(struct file *file);
71 extern long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg);
72
73 #else
74
shmem_fcntl(struct file * f,unsigned int c,unsigned long a)75 static inline long shmem_fcntl(struct file *f, unsigned int c, unsigned long a)
76 {
77 return -EINVAL;
78 }
79
80 #endif
81
82 #endif
83