diff options
Diffstat (limited to 'include/linux/iomap.h')
| -rw-r--r-- | include/linux/iomap.h | 129 |
1 files changed, 95 insertions, 34 deletions
diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 7aa5d6117936..8b09463dae0d 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -4,6 +4,7 @@ #include <linux/atomic.h> #include <linux/bitmap.h> +#include <linux/blk_types.h> #include <linux/mm.h> #include <linux/types.h> #include <linux/mm_types.h> @@ -12,6 +13,7 @@ struct address_space; struct fiemap_extent_info; struct inode; +struct iomap_writepage_ctx; struct iov_iter; struct kiocb; struct page; @@ -21,28 +23,45 @@ struct vm_fault; /* * Types of block ranges for iomap mappings: */ -#define IOMAP_HOLE 0x01 /* no blocks allocated, need allocation */ -#define IOMAP_DELALLOC 0x02 /* delayed allocation blocks */ -#define IOMAP_MAPPED 0x03 /* blocks allocated at @addr */ -#define IOMAP_UNWRITTEN 0x04 /* blocks allocated at @addr in unwritten state */ -#define IOMAP_INLINE 0x05 /* data inline in the inode */ +#define IOMAP_HOLE 0 /* no blocks allocated, need allocation */ +#define IOMAP_DELALLOC 1 /* delayed allocation blocks */ +#define IOMAP_MAPPED 2 /* blocks allocated at @addr */ +#define IOMAP_UNWRITTEN 3 /* blocks allocated at @addr in unwritten state */ +#define IOMAP_INLINE 4 /* data inline in the inode */ /* - * Flags for all iomap mappings: + * Flags reported by the file system from iomap_begin: + * + * IOMAP_F_NEW indicates that the blocks have been newly allocated and need + * zeroing for areas that no data is copied to. * * IOMAP_F_DIRTY indicates the inode has uncommitted metadata needed to access * written data and requires fdatasync to commit them to persistent storage. + * This needs to take into account metadata changes that *may* be made at IO + * completion, such as file size updates from direct IO. + * + * IOMAP_F_SHARED indicates that the blocks are shared, and will need to be + * unshared as part a write. + * + * IOMAP_F_MERGED indicates that the iomap contains the merge of multiple block + * mappings. + * + * IOMAP_F_BUFFER_HEAD indicates that the file system requires the use of + * buffer heads for this mapping. */ -#define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */ -#define IOMAP_F_DIRTY 0x02 /* uncommitted metadata */ -#define IOMAP_F_BUFFER_HEAD 0x04 /* file system requires buffer heads */ -#define IOMAP_F_SIZE_CHANGED 0x08 /* file size has changed */ +#define IOMAP_F_NEW 0x01 +#define IOMAP_F_DIRTY 0x02 +#define IOMAP_F_SHARED 0x04 +#define IOMAP_F_MERGED 0x08 +#define IOMAP_F_BUFFER_HEAD 0x10 /* - * Flags that only need to be reported for IOMAP_REPORT requests: + * Flags set by the core iomap code during operations: + * + * IOMAP_F_SIZE_CHANGED indicates to the iomap_end method that the file size + * has changed as the result of this write operation. */ -#define IOMAP_F_MERGED 0x10 /* contains multiple blocks/extents */ -#define IOMAP_F_SHARED 0x20 /* block shared with another file */ +#define IOMAP_F_SIZE_CHANGED 0x100 /* * Flags from 0x1000 up are for file system specific usage: @@ -110,7 +129,8 @@ struct iomap_ops { * The actual length is returned in iomap->length. */ int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length, - unsigned flags, struct iomap *iomap); + unsigned flags, struct iomap *iomap, + struct iomap *srcmap); /* * Commit and/or unreserve space previous allocated using iomap_begin. @@ -126,29 +146,12 @@ struct iomap_ops { * Main iomap iterator function. */ typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len, - void *data, struct iomap *iomap); + void *data, struct iomap *iomap, struct iomap *srcmap); loff_t iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, const struct iomap_ops *ops, void *data, iomap_actor_t actor); -/* - * Structure allocate for each page when block size < PAGE_SIZE to track - * sub-page uptodate status and I/O completions. - */ -struct iomap_page { - atomic_t read_count; - atomic_t write_count; - DECLARE_BITMAP(uptodate, PAGE_SIZE / 512); -}; - -static inline struct iomap_page *to_iomap_page(struct page *page) -{ - if (page_has_private(page)) - return (struct iomap_page *)page_private(page); - return NULL; -} - ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from, const struct iomap_ops *ops); int iomap_readpage(struct page *page, const struct iomap_ops *ops); @@ -166,7 +169,7 @@ int iomap_migrate_page(struct address_space *mapping, struct page *newpage, #else #define iomap_migrate_page NULL #endif -int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len, +int iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len, const struct iomap_ops *ops); int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero, const struct iomap_ops *ops); @@ -184,6 +187,63 @@ sector_t iomap_bmap(struct address_space *mapping, sector_t bno, const struct iomap_ops *ops); /* + * Structure for writeback I/O completions. + */ +struct iomap_ioend { + struct list_head io_list; /* next ioend in chain */ + u16 io_type; + u16 io_flags; /* IOMAP_F_* */ + struct inode *io_inode; /* file being written to */ + size_t io_size; /* size of the extent */ + loff_t io_offset; /* offset in the file */ + void *io_private; /* file system private data */ + struct bio *io_bio; /* bio being built */ + struct bio io_inline_bio; /* MUST BE LAST! */ +}; + +struct iomap_writeback_ops { + /* + * Required, maps the blocks so that writeback can be performed on + * the range starting at offset. + */ + int (*map_blocks)(struct iomap_writepage_ctx *wpc, struct inode *inode, + loff_t offset); + + /* + * Optional, allows the file systems to perform actions just before + * submitting the bio and/or override the bio end_io handler for complex + * operations like copy on write extent manipulation or unwritten extent + * conversions. + */ + int (*prepare_ioend)(struct iomap_ioend *ioend, int status); + + /* + * Optional, allows the file system to discard state on a page where + * we failed to submit any I/O. + */ + void (*discard_page)(struct page *page); +}; + +struct iomap_writepage_ctx { + struct iomap iomap; + struct iomap_ioend *ioend; + const struct iomap_writeback_ops *ops; +}; + +void iomap_finish_ioends(struct iomap_ioend *ioend, int error); +void iomap_ioend_try_merge(struct iomap_ioend *ioend, + struct list_head *more_ioends, + void (*merge_private)(struct iomap_ioend *ioend, + struct iomap_ioend *next)); +void iomap_sort_ioends(struct list_head *ioend_list); +int iomap_writepage(struct page *page, struct writeback_control *wbc, + struct iomap_writepage_ctx *wpc, + const struct iomap_writeback_ops *ops); +int iomap_writepages(struct address_space *mapping, + struct writeback_control *wbc, struct iomap_writepage_ctx *wpc, + const struct iomap_writeback_ops *ops); + +/* * Flags for direct I/O ->end_io: */ #define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */ @@ -195,7 +255,8 @@ struct iomap_dio_ops { }; ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, - const struct iomap_ops *ops, const struct iomap_dio_ops *dops); + const struct iomap_ops *ops, const struct iomap_dio_ops *dops, + bool wait_for_completion); int iomap_dio_iopoll(struct kiocb *kiocb, bool spin); #ifdef CONFIG_SWAP |