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-rw-r--r--include/linux/bio.h109
-rw-r--r--include/linux/fs.h64
-rw-r--r--include/linux/pipe_fs_i.h5
-rw-r--r--include/linux/splice.h12
4 files changed, 185 insertions, 5 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h
index b900d2c67d2..b89cf2d8289 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -504,6 +504,115 @@ static inline int bio_has_data(struct bio *bio)
return bio && bio->bi_io_vec != NULL;
}
+/*
+ * BIO list managment for use by remapping drivers (e.g. DM or MD).
+ *
+ * A bio_list anchors a singly-linked list of bios chained through the bi_next
+ * member of the bio. The bio_list also caches the last list member to allow
+ * fast access to the tail.
+ */
+struct bio_list {
+ struct bio *head;
+ struct bio *tail;
+};
+
+static inline int bio_list_empty(const struct bio_list *bl)
+{
+ return bl->head == NULL;
+}
+
+static inline void bio_list_init(struct bio_list *bl)
+{
+ bl->head = bl->tail = NULL;
+}
+
+#define bio_list_for_each(bio, bl) \
+ for (bio = (bl)->head; bio; bio = bio->bi_next)
+
+static inline unsigned bio_list_size(const struct bio_list *bl)
+{
+ unsigned sz = 0;
+ struct bio *bio;
+
+ bio_list_for_each(bio, bl)
+ sz++;
+
+ return sz;
+}
+
+static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
+{
+ bio->bi_next = NULL;
+
+ if (bl->tail)
+ bl->tail->bi_next = bio;
+ else
+ bl->head = bio;
+
+ bl->tail = bio;
+}
+
+static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
+{
+ bio->bi_next = bl->head;
+
+ bl->head = bio;
+
+ if (!bl->tail)
+ bl->tail = bio;
+}
+
+static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
+{
+ if (!bl2->head)
+ return;
+
+ if (bl->tail)
+ bl->tail->bi_next = bl2->head;
+ else
+ bl->head = bl2->head;
+
+ bl->tail = bl2->tail;
+}
+
+static inline void bio_list_merge_head(struct bio_list *bl,
+ struct bio_list *bl2)
+{
+ if (!bl2->head)
+ return;
+
+ if (bl->head)
+ bl2->tail->bi_next = bl->head;
+ else
+ bl->tail = bl2->tail;
+
+ bl->head = bl2->head;
+}
+
+static inline struct bio *bio_list_pop(struct bio_list *bl)
+{
+ struct bio *bio = bl->head;
+
+ if (bio) {
+ bl->head = bl->head->bi_next;
+ if (!bl->head)
+ bl->tail = NULL;
+
+ bio->bi_next = NULL;
+ }
+
+ return bio;
+}
+
+static inline struct bio *bio_list_get(struct bio_list *bl)
+{
+ struct bio *bio = bl->head;
+
+ bl->head = bl->tail = NULL;
+
+ return bio;
+}
+
#if defined(CONFIG_BLK_DEV_INTEGRITY)
#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 562d2855cf3..e766be0d432 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -87,6 +87,60 @@ struct inodes_stat_t {
*/
#define FMODE_NOCMTIME ((__force fmode_t)2048)
+/*
+ * The below are the various read and write types that we support. Some of
+ * them include behavioral modifiers that send information down to the
+ * block layer and IO scheduler. Terminology:
+ *
+ * The block layer uses device plugging to defer IO a little bit, in
+ * the hope that we will see more IO very shortly. This increases
+ * coalescing of adjacent IO and thus reduces the number of IOs we
+ * have to send to the device. It also allows for better queuing,
+ * if the IO isn't mergeable. If the caller is going to be waiting
+ * for the IO, then he must ensure that the device is unplugged so
+ * that the IO is dispatched to the driver.
+ *
+ * All IO is handled async in Linux. This is fine for background
+ * writes, but for reads or writes that someone waits for completion
+ * on, we want to notify the block layer and IO scheduler so that they
+ * know about it. That allows them to make better scheduling
+ * decisions. So when the below references 'sync' and 'async', it
+ * is referencing this priority hint.
+ *
+ * With that in mind, the available types are:
+ *
+ * READ A normal read operation. Device will be plugged.
+ * READ_SYNC A synchronous read. Device is not plugged, caller can
+ * immediately wait on this read without caring about
+ * unplugging.
+ * READA Used for read-ahead operations. Lower priority, and the
+ * block layer could (in theory) choose to ignore this
+ * request if it runs into resource problems.
+ * WRITE A normal async write. Device will be plugged.
+ * SWRITE Like WRITE, but a special case for ll_rw_block() that
+ * tells it to lock the buffer first. Normally a buffer
+ * must be locked before doing IO.
+ * WRITE_SYNC_PLUG Synchronous write. Identical to WRITE, but passes down
+ * the hint that someone will be waiting on this IO
+ * shortly. The device must still be unplugged explicitly,
+ * WRITE_SYNC_PLUG does not do this as we could be
+ * submitting more writes before we actually wait on any
+ * of them.
+ * WRITE_SYNC Like WRITE_SYNC_PLUG, but also unplugs the device
+ * immediately after submission. The write equivalent
+ * of READ_SYNC.
+ * WRITE_ODIRECT Special case write for O_DIRECT only.
+ * SWRITE_SYNC
+ * SWRITE_SYNC_PLUG Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer.
+ * See SWRITE.
+ * WRITE_BARRIER Like WRITE, but tells the block layer that all
+ * previously submitted writes must be safely on storage
+ * before this one is started. Also guarantees that when
+ * this write is complete, it itself is also safely on
+ * storage. Prevents reordering of writes on both sides
+ * of this IO.
+ *
+ */
#define RW_MASK 1
#define RWA_MASK 2
#define READ 0
@@ -102,6 +156,11 @@ struct inodes_stat_t {
(SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))
#define SWRITE_SYNC (SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))
#define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER))
+
+/*
+ * These aren't really reads or writes, they pass down information about
+ * parts of device that are now unused by the file system.
+ */
#define DISCARD_NOBARRIER (1 << BIO_RW_DISCARD)
#define DISCARD_BARRIER ((1 << BIO_RW_DISCARD) | (1 << BIO_RW_BARRIER))
@@ -738,9 +797,6 @@ enum inode_i_mutex_lock_class
I_MUTEX_QUOTA
};
-extern void inode_double_lock(struct inode *inode1, struct inode *inode2);
-extern void inode_double_unlock(struct inode *inode1, struct inode *inode2);
-
/*
* NOTE: in a 32bit arch with a preemptable kernel and
* an UP compile the i_size_read/write must be atomic
@@ -2150,8 +2206,6 @@ extern ssize_t generic_file_splice_read(struct file *, loff_t *,
struct pipe_inode_info *, size_t, unsigned int);
extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
struct file *, loff_t *, size_t, unsigned int);
-extern ssize_t generic_file_splice_write_nolock(struct pipe_inode_info *,
- struct file *, loff_t *, size_t, unsigned int);
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
struct file *out, loff_t *, size_t len, unsigned int flags);
extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 8e4120285f7..c8f038554e8 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -134,6 +134,11 @@ struct pipe_buf_operations {
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE
+/* Pipe lock and unlock operations */
+void pipe_lock(struct pipe_inode_info *);
+void pipe_unlock(struct pipe_inode_info *);
+void pipe_double_lock(struct pipe_inode_info *, struct pipe_inode_info *);
+
/* Drop the inode semaphore and wait for a pipe event, atomically */
void pipe_wait(struct pipe_inode_info *pipe);
diff --git a/include/linux/splice.h b/include/linux/splice.h
index 528dcb93c2f..5f3faa9d15a 100644
--- a/include/linux/splice.h
+++ b/include/linux/splice.h
@@ -36,6 +36,8 @@ struct splice_desc {
void *data; /* cookie */
} u;
loff_t pos; /* file position */
+ size_t num_spliced; /* number of bytes already spliced */
+ bool need_wakeup; /* need to wake up writer */
};
struct partial_page {
@@ -66,6 +68,16 @@ extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
splice_actor *);
extern ssize_t __splice_from_pipe(struct pipe_inode_info *,
struct splice_desc *, splice_actor *);
+extern int splice_from_pipe_feed(struct pipe_inode_info *, struct splice_desc *,
+ splice_actor *);
+extern int splice_from_pipe_next(struct pipe_inode_info *,
+ struct splice_desc *);
+extern void splice_from_pipe_begin(struct splice_desc *);
+extern void splice_from_pipe_end(struct pipe_inode_info *,
+ struct splice_desc *);
+extern int pipe_to_file(struct pipe_inode_info *, struct pipe_buffer *,
+ struct splice_desc *);
+
extern ssize_t splice_to_pipe(struct pipe_inode_info *,
struct splice_pipe_desc *);
extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,