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Diffstat (limited to 'include/linux/shmem_fs.h')
-rw-r--r--include/linux/shmem_fs.h25
1 files changed, 24 insertions, 1 deletions
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index d02270072a34..e2069b3179c4 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -10,6 +10,7 @@
#include <linux/xattr.h>
#include <linux/fs_parser.h>
#include <linux/userfaultfd_k.h>
+#include <linux/bits.h>
struct swap_iocb;
@@ -19,6 +20,19 @@ struct swap_iocb;
#define SHMEM_MAXQUOTAS 2
#endif
+/* Suppress pre-accounting of the entire object size. */
+#define SHMEM_F_NORESERVE BIT(0)
+/* Disallow swapping. */
+#define SHMEM_F_LOCKED BIT(1)
+/*
+ * Disallow growing, shrinking, or hole punching in the inode. Combined with
+ * folio pinning, makes sure the inode's mapping stays fixed.
+ *
+ * In some ways similar to F_SEAL_GROW | F_SEAL_SHRINK, but can be removed and
+ * isn't directly visible to userspace.
+ */
+#define SHMEM_F_MAPPING_FROZEN BIT(2)
+
struct shmem_inode_info {
spinlock_t lock;
unsigned int seals; /* shmem seals */
@@ -112,7 +126,7 @@ struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
pgoff_t index, gfp_t gfp_mask);
int shmem_writeout(struct folio *folio, struct swap_iocb **plug,
struct list_head *folio_list);
-void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
+void shmem_truncate_range(struct inode *inode, loff_t start, uoff_t end);
int shmem_unuse(unsigned int type);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -186,6 +200,15 @@ static inline bool shmem_file(struct file *file)
return shmem_mapping(file->f_mapping);
}
+/* Must be called with inode lock taken exclusive. */
+static inline void shmem_freeze(struct inode *inode, bool freeze)
+{
+ if (freeze)
+ SHMEM_I(inode)->flags |= SHMEM_F_MAPPING_FROZEN;
+ else
+ SHMEM_I(inode)->flags &= ~SHMEM_F_MAPPING_FROZEN;
+}
+
/*
* If fallocate(FALLOC_FL_KEEP_SIZE) has been used, there may be pages
* beyond i_size's notion of EOF, which fallocate has committed to reserving: