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-rw-r--r--include/linux/shmem_fs.h89
1 files changed, 89 insertions, 0 deletions
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
new file mode 100644
index 000000000..3ab7d1805
--- /dev/null
+++ b/include/linux/shmem_fs.h
@@ -0,0 +1,89 @@
+#ifndef __SHMEM_FS_H
+#define __SHMEM_FS_H
+
+#include <linux/file.h>
+#include <linux/swap.h>
+#include <linux/mempolicy.h>
+#include <linux/pagemap.h>
+#include <linux/percpu_counter.h>
+#include <linux/xattr.h>
+
+/* inode in-kernel data */
+
+struct shmem_inode_info {
+ spinlock_t lock;
+ unsigned int seals; /* shmem seals */
+ unsigned long flags;
+ unsigned long alloced; /* data pages alloced to file */
+ union {
+ unsigned long swapped; /* subtotal assigned to swap */
+ char *symlink; /* unswappable short symlink */
+ };
+ struct shared_policy policy; /* NUMA memory alloc policy */
+ struct list_head swaplist; /* chain of maybes on swap */
+ struct simple_xattrs xattrs; /* list of xattrs */
+ struct inode vfs_inode;
+};
+
+struct shmem_sb_info {
+ struct mutex idr_lock;
+ bool idr_nouse;
+ struct idr idr; /* manages inode-number */
+ unsigned long max_blocks; /* How many blocks are allowed */
+ struct percpu_counter used_blocks; /* How many are allocated */
+ int max_inodes; /* How many inodes are allowed */
+ int free_inodes; /* How many are left for allocation */
+ spinlock_t stat_lock; /* Serialize shmem_sb_info changes */
+ kuid_t uid; /* Mount uid for root directory */
+ kgid_t gid; /* Mount gid for root directory */
+ umode_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 shmem_init(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,
+ int atomic_copy);
+extern struct file *shmem_kernel_file_setup(const char *name, loff_t size,
+ unsigned long flags, int atomic_copy);
+extern int shmem_zero_setup(struct vm_area_struct *);
+extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
+extern bool shmem_mapping(struct address_space *mapping);
+extern void shmem_unlock_mapping(struct address_space *mapping);
+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);
+
+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));
+}
+
+#ifdef CONFIG_TMPFS
+
+extern int shmem_add_seals(struct file *file, unsigned int seals);
+extern int shmem_get_seals(struct file *file);
+extern long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg);
+
+#else
+
+static inline long shmem_fcntl(struct file *f, unsigned int c, unsigned long a)
+{
+ return -EINVAL;
+}
+
+#endif
+
+#endif