include/linux/shmem_fs.h

   1 #ifndef __SHMEM_FS_H
   2 #define __SHMEM_FS_H
   3
   4 #include <linux/swap.h>
   5 #include <linux/mempolicy.h>
   6 #include <linux/percpu_counter.h>
   7
   8 /* inode in-kernel data */
   9
  10 #define SHMEM_NR_DIRECT 16
  11
  12 struct shmem_inode_info {
  13         spinlock_t              lock;
  14         unsigned long           flags;
  15         unsigned long           alloced;        /* data pages alloced to file */
  16         unsigned long           swapped;        /* subtotal assigned to swap */
  17         unsigned long           next_index;     /* highest alloced index + 1 */
  18         struct shared_policy    policy;         /* NUMA memory alloc policy */
  19         struct page             *i_indirect;    /* top indirect blocks page */
  20         swp_entry_t             i_direct[SHMEM_NR_DIRECT]; /* first blocks */
  21         struct list_head        swaplist;       /* chain of maybes on swap */
  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         uid_t uid;                  /* Mount uid for root directory */
  32         gid_t gid;                  /* Mount gid for root directory */
  33         mode_t mode;                /* Mount mode for root directory */
  34         struct mempolicy *mpol;     /* default memory policy for mappings */
  35 };
  36
  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 extern int init_tmpfs(void);
  43 extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
  44
  45 #endif