[mirror_ubuntu-bionic-kernel.git] / include / linux / shmem_fs.h

#ifndef __SHMEM_FS_H
#define __SHMEM_FS_H

#include <linux/swap.h>
#include <linux/mempolicy.h>
#include <linux/pagemap.h>
#include <linux/percpu_counter.h>

/* inode in-kernel data */

#define SHMEM_NR_DIRECT 16

#define SHMEM_SYMLINK_INLINE_LEN (SHMEM_NR_DIRECT * sizeof(swp_entry_t))

struct shmem_inode_info {
	spinlock_t		lock;
	unsigned long		flags;
	unsigned long		alloced;	/* data pages alloced to file */
	unsigned long		swapped;	/* subtotal assigned to swap */
	struct shared_policy	policy;		/* NUMA memory alloc policy */
	union {
		swp_entry_t	i_direct[SHMEM_NR_DIRECT]; /* first blocks */
		char		inline_symlink[SHMEM_SYMLINK_INLINE_LEN];
	};
	struct list_head	swaplist;	/* chain of maybes on swap */
	struct list_head	xattr_list;	/* list of shmem_xattr */
	struct inode		vfs_inode;
};

struct shmem_sb_info {
	unsigned long max_blocks;   /* How many blocks are allowed */
	struct percpu_counter used_blocks;  /* How many are allocated */
	unsigned long max_inodes;   /* How many inodes are allowed */
	unsigned long free_inodes;  /* How many are left for allocation */
	spinlock_t stat_lock;	    /* Serialize shmem_sb_info changes */
	uid_t uid;		    /* Mount uid for root directory */
	gid_t gid;		    /* Mount gid for root directory */
	mode_t mode;		    /* Mount mode for root directory */
	struct mempolicy *mpol;     /* default memory policy for mappings */
};

static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
{
	return container_of(inode, struct shmem_inode_info, vfs_inode);
}

/*
 * Functions in mm/shmem.c called directly from elsewhere:
 */
extern int init_tmpfs(void);
extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
extern struct file *shmem_file_setup(const char *name,
					loff_t size, unsigned long flags);
extern int shmem_zero_setup(struct vm_area_struct *);
extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
					pgoff_t index, gfp_t gfp_mask);
extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
extern int shmem_unuse(swp_entry_t entry, struct page *page);
extern void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
					struct page **pagep, swp_entry_t *ent);

static inline struct page *shmem_read_mapping_page(
				struct address_space *mapping, pgoff_t index)
{
	return shmem_read_mapping_page_gfp(mapping, index,
					mapping_gfp_mask(mapping));
}

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef __SHMEM_FS_H
	2	#define __SHMEM_FS_H
	3
	4	#include <linux/swap.h>
	5	#include <linux/mempolicy.h>
d9d90e5e	6	#include <linux/pagemap.h>
7e496299	7	#include <linux/percpu_counter.h>
1da177e4 LT	8
	9	/* inode in-kernel data */
	10
	11	#define SHMEM_NR_DIRECT 16
	12
b09e0fa4 EP	13	#define SHMEM_SYMLINK_INLINE_LEN (SHMEM_NR_DIRECT * sizeof(swp_entry_t))
b09e0fa4 EP	14
1da177e4 LT	15	struct 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 */
1da177e4	20	struct shared_policy policy; /* NUMA memory alloc policy */
b09e0fa4 EP	21	union {
	22	swp_entry_t i_direct[SHMEM_NR_DIRECT]; /* first blocks */
	23	char inline_symlink[SHMEM_SYMLINK_INLINE_LEN];
	24	};
1da177e4	25	struct list_head swaplist; /* chain of maybes on swap */
b09e0fa4	26	struct list_head xattr_list; /* list of shmem_xattr */
1da177e4 LT	27	struct inode vfs_inode;
	28	};
	29
	30	struct shmem_sb_info {
	31	unsigned long max_blocks; /* How many blocks are allowed */
7e496299	32	struct percpu_counter used_blocks; /* How many are allocated */
1da177e4 LT	33	unsigned long max_inodes; /* How many inodes are allowed */
1da177e4 LT	34	unsigned long free_inodes; /* How many are left for allocation */
680d794b AM	35	spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
	36	uid_t uid; /* Mount uid for root directory */
	37	gid_t gid; /* Mount gid for root directory */
	38	mode_t mode; /* Mount mode for root directory */
71fe804b	39	struct mempolicy mpol; / default memory policy for mappings */
1da177e4 LT	40	};
	41
	42	static inline struct shmem_inode_info SHMEM_I(struct inode inode)
	43	{
	44	return container_of(inode, struct shmem_inode_info, vfs_inode);
	45	}
	46
072441e2 HD	47	/*
	48	* Functions in mm/shmem.c called directly from elsewhere:
	49	*/
2b2af54a KS	50	extern int init_tmpfs(void);
2b2af54a KS	51	extern int shmem_fill_super(struct super_block sb, void data, int silent);
072441e2 HD	52	extern struct file shmem_file_setup(const char name,
	53	loff_t size, unsigned long flags);
	54	extern int shmem_zero_setup(struct vm_area_struct *);
	55	extern int shmem_lock(struct file file, int lock, struct user_struct user);
d9d90e5e HD	56	extern struct page shmem_read_mapping_page_gfp(struct address_space mapping,
d9d90e5e HD	57	pgoff_t index, gfp_t gfp_mask);
94c1e62d	58	extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
072441e2 HD	59	extern int shmem_unuse(swp_entry_t entry, struct page *page);
	60	extern void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
	61	struct page *pagep, swp_entry_t ent);
2b2af54a	62
d9d90e5e HD	63	static inline struct page *shmem_read_mapping_page(
	64	struct address_space *mapping, pgoff_t index)
	65	{
	66	return shmem_read_mapping_page_gfp(mapping, index,
	67	mapping_gfp_mask(mapping));
	68	}
	69
1da177e4	70	#endif