Dave Kleikamp
2012-Feb-27 21:20 UTC
[Ocfs2-devel] [RFC PATCH 19/22] ocfs2: add support for read_iter, write_iter, and direct_IO_bvec
From: Zach Brown <zab at zabbo.net>
ocfs2's .aio_read and .aio_write methods are changed to take
iov_iter and pass it to generic functions. Wrappers are made to pack
the iovecs into iters and call these new functions.
ocfs2_direct_IO() is trivial enough that a new function is made which
passes the bvec down to the generic direct path.
Signed-off-by: Dave Kleikamp <dave.kleikamp at oracle.com>
Cc: Zach Brown <zab at zabbo.net>
Cc: Mark Fasheh <mfasheh at suse.com>
Cc: Joel Becker <jlbec at evilplan.org>
Cc: ocfs2-devel at oss.oracle.com
---
fs/ocfs2/aops.c | 31 ++++++++++++++++++
fs/ocfs2/file.c | 82 ++++++++++++++++++++++++++++++++++--------------
fs/ocfs2/ocfs2_trace.h | 6 +++-
3 files changed, 94 insertions(+), 25 deletions(-)
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 78b68af..80183df 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -645,6 +645,36 @@ static ssize_t ocfs2_direct_IO(int rw,
ocfs2_dio_end_io, NULL, 0);
}
+static ssize_t ocfs2_direct_IO_bvec(int rw,
+ struct kiocb *iocb,
+ struct bio_vec *bvec,
+ loff_t offset,
+ unsigned long bvec_len)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode =
file->f_path.dentry->d_inode->i_mapping->host;
+ int ret;
+
+ /*
+ * Fallback to buffered I/O if we see an inode without
+ * extents.
+ */
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ return 0;
+
+ /* Fallback to buffered I/O if we are appending. */
+ if (i_size_read(inode) <= offset)
+ return 0;
+
+ ret = blockdev_direct_IO_bvec_no_locking(rw, iocb, inode,
+ inode->i_sb->s_bdev, bvec,
+ offset, bvec_len,
+ ocfs2_direct_IO_get_blocks,
+ ocfs2_dio_end_io);
+
+ return ret;
+}
+
static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
u32 cpos,
unsigned int *start,
@@ -2091,6 +2121,7 @@ const struct address_space_operations ocfs2_aops = {
.write_end = ocfs2_write_end,
.bmap = ocfs2_bmap,
.direct_IO = ocfs2_direct_IO,
+ .direct_IO_bvec = ocfs2_direct_IO_bvec,
.invalidatepage = ocfs2_invalidatepage,
.releasepage = ocfs2_releasepage,
.migratepage = buffer_migrate_page,
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 061591a..f636813 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2233,15 +2233,13 @@ out:
return ret;
}
-static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
- const struct iovec *iov,
- unsigned long nr_segs,
- loff_t pos)
+static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
+ struct iov_iter *iter,
+ loff_t pos)
{
int ret, direct_io, appending, rw_level, have_alloc_sem = 0;
int can_do_direct, has_refcount = 0;
ssize_t written = 0;
- size_t ocount; /* original count */
size_t count; /* after file limit checks */
loff_t old_size, *ppos = &iocb->ki_pos;
u32 old_clusters;
@@ -2252,11 +2250,11 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
OCFS2_MOUNT_COHERENCY_BUFFERED);
int unaligned_dio = 0;
- trace_ocfs2_file_aio_write(inode, file, file->f_path.dentry,
+ trace_ocfs2_file_write_iter(inode, file, file->f_path.dentry,
(unsigned long long)OCFS2_I(inode)->ip_blkno,
file->f_path.dentry->d_name.len,
file->f_path.dentry->d_name.name,
- (unsigned int)nr_segs);
+ (unsigned long long)pos);
if (iocb->ki_left == 0)
return 0;
@@ -2358,28 +2356,24 @@ relock:
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb, rw_level);
- ret = generic_segment_checks(iov, &nr_segs, &ocount,
- VERIFY_READ);
- if (ret)
- goto out_dio;
- count = ocount;
+ count = iov_iter_count(iter);
ret = generic_write_checks(file, ppos, &count,
S_ISBLK(inode->i_mode));
if (ret)
goto out_dio;
if (direct_io) {
- written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos,
- ppos, count, ocount);
+ written = generic_file_direct_write_iter(iocb, iter, *ppos,
+ ppos, count);
if (written < 0) {
ret = written;
goto out_dio;
}
} else {
current->backing_dev_info = file->f_mapping->backing_dev_info;
- written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos,
- ppos, count, 0);
+ written = generic_file_buffered_write_iter(iocb, iter, *ppos,
+ ppos, 0);
current->backing_dev_info = NULL;
}
@@ -2440,6 +2434,25 @@ out_sems:
return ret;
}
+static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
+ const struct iovec *iov,
+ unsigned long nr_segs,
+ loff_t pos)
+{
+ struct iov_iter iter;
+ size_t count;
+ int ret;
+
+ count = 0;
+ ret = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
+ if (ret)
+ return ret;
+
+ iov_iter_init(&iter, iov, nr_segs, count, 0);
+
+ return ocfs2_file_write_iter(iocb, &iter, pos);
+}
+
static int ocfs2_splice_to_file(struct pipe_inode_info *pipe,
struct file *out,
struct splice_desc *sd)
@@ -2553,19 +2566,18 @@ bail:
return ret;
}
-static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
- const struct iovec *iov,
- unsigned long nr_segs,
+static ssize_t ocfs2_file_read_iter(struct kiocb *iocb,
+ struct iov_iter *iter,
loff_t pos)
{
int ret = 0, rw_level = -1, have_alloc_sem = 0, lock_level = 0;
struct file *filp = iocb->ki_filp;
struct inode *inode = filp->f_path.dentry->d_inode;
- trace_ocfs2_file_aio_read(inode, filp, filp->f_path.dentry,
+ trace_ocfs2_file_read_iter(inode, filp, filp->f_path.dentry,
(unsigned long long)OCFS2_I(inode)->ip_blkno,
filp->f_path.dentry->d_name.len,
- filp->f_path.dentry->d_name.name, nr_segs);
+ filp->f_path.dentry->d_name.name, pos);
if (!inode) {
@@ -2601,7 +2613,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
*
* Take and drop the meta data lock to update inode fields
* like i_size. This allows the checks down below
- * generic_file_aio_read() a chance of actually working.
+ * generic_file_read_iter() a chance of actually working.
*/
ret = ocfs2_inode_lock_atime(inode, filp->f_vfsmnt, &lock_level);
if (ret < 0) {
@@ -2610,8 +2622,8 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
}
ocfs2_inode_unlock(inode, lock_level);
- ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
- trace_generic_file_aio_read_ret(ret);
+ ret = generic_file_read_iter(iocb, iter, iocb->ki_pos);
+ trace_generic_file_read_iter_ret(ret);
/* buffered aio wouldn't have proper lock coverage today */
BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
@@ -2683,6 +2695,24 @@ out:
return offset;
}
+static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
+ const struct iovec *iov,
+ unsigned long nr_segs,
+ loff_t pos)
+{
+ struct iov_iter iter;
+ size_t count;
+ int ret;
+
+ ret = generic_segment_checks(iov, &nr_segs, &count, VERIFY_WRITE);
+ if (ret)
+ return ret;
+
+ iov_iter_init(&iter, iov, nr_segs, count, 0);
+
+ return ocfs2_file_read_iter(iocb, &iter, pos);
+}
+
const struct inode_operations ocfs2_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
@@ -2716,6 +2746,8 @@ const struct file_operations ocfs2_fops = {
.open = ocfs2_file_open,
.aio_read = ocfs2_file_aio_read,
.aio_write = ocfs2_file_aio_write,
+ .read_iter = ocfs2_file_read_iter,
+ .write_iter = ocfs2_file_write_iter,
.unlocked_ioctl = ocfs2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ocfs2_compat_ioctl,
@@ -2764,6 +2796,8 @@ const struct file_operations ocfs2_fops_no_plocks = {
.open = ocfs2_file_open,
.aio_read = ocfs2_file_aio_read,
.aio_write = ocfs2_file_aio_write,
+ .read_iter = ocfs2_file_read_iter,
+ .write_iter = ocfs2_file_write_iter,
.unlocked_ioctl = ocfs2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ocfs2_compat_ioctl,
diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h
index 3b481f4..8409f00 100644
--- a/fs/ocfs2/ocfs2_trace.h
+++ b/fs/ocfs2/ocfs2_trace.h
@@ -1312,12 +1312,16 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_sync_file);
DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_write);
+DEFINE_OCFS2_FILE_OPS(ocfs2_file_write_iter);
+
DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write);
DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read);
DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_read);
+DEFINE_OCFS2_FILE_OPS(ocfs2_file_read_iter);
+
DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file);
DEFINE_OCFS2_ULL_ULL_EVENT(ocfs2_truncate_file_error);
@@ -1474,7 +1478,7 @@ TRACE_EVENT(ocfs2_prepare_inode_for_write,
__entry->direct_io, __entry->has_refcount)
);
-DEFINE_OCFS2_INT_EVENT(generic_file_aio_read_ret);
+DEFINE_OCFS2_INT_EVENT(generic_file_read_iter_ret);
/* End of trace events for fs/ocfs2/file.c. */
--
1.7.9.2