diff mbox

Re: [PATCH V3 1/2] ceph: Implement readv/preadv for sync operation.

Message ID 201309101112568427989@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

majianpeng Sept. 10, 2013, 3:13 a.m. UTC
>On 09/10/2013 10:04 AM, majianpeng wrote:

>> For readv/preadv sync-operatoin, ceph only do the first iov.

>> It don't think other iovs.Now implement this.

>> 

>> V3: 

>>    modify some bug.

>> V2:

>>   -add generic_segment_checks

>>   -using struct iov_iter replace cloning the iovs.

>>   -return previous successfully copied if ceph_copy_page_vector_to_user

>>    met error.

>> 

>> 

>> Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>

>> Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>

>

>don't add people's Reviewed-by unless they say "you can"

>

>> ---

>>  fs/ceph/file.c | 157 ++++++++++++++++++++++++++++++++++++++-------------------

>>  1 file changed, 106 insertions(+), 51 deletions(-)

>> 

>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c

>> index 3de8982..8f20eb4 100644

>> --- a/fs/ceph/file.c

>> +++ b/fs/ceph/file.c

>> @@ -408,51 +408,94 @@ more:

>>   *

>>   * If the read spans object boundary, just do multiple reads.

>>   */

>> -static ssize_t ceph_sync_read(struct file *file, char __user *data,

>> -			      unsigned len, loff_t *poff, int *checkeof)

>> +static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,

>> +				int *checkeof)

>>  {

>> +	struct file *file = iocb->ki_filp;

>>  	struct inode *inode = file_inode(file);

>>  	struct page **pages;

>> -	u64 off = *poff;

>> +	u64 off = iocb->ki_pos;

>>  	int num_pages, ret;

>>  

>> -	dout("sync_read on file %p %llu~%u %s\n", file, off, len,

>> +	dout("sync_read on file %p %llu~%u %s\n", file, off,

>> +	     (unsigned)iocb->ki_left,

>>  	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");

>> -

>> -	if (file->f_flags & O_DIRECT) {

>> -		num_pages = calc_pages_for((unsigned long)data, len);

>> -		pages = ceph_get_direct_page_vector(data, num_pages, true);

>> -	} else {

>> -		num_pages = calc_pages_for(off, len);

>> -		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);

>> -	}

>> -	if (IS_ERR(pages))

>> -		return PTR_ERR(pages);

>> -

>>  	/*

>>  	 * flush any page cache pages in this range.  this

>>  	 * will make concurrent normal and sync io slow,

>>  	 * but it will at least behave sensibly when they are

>>  	 * in sequence.

>>  	 */

>> -	ret = filemap_write_and_wait(inode->i_mapping);

>> +	ret = filemap_write_and_wait_range(inode->i_mapping, off,

>> +						off + iocb->ki_left);

>>  	if (ret < 0)

>> -		goto done;

>> -

>> -	ret = striped_read(inode, off, len, pages, num_pages, checkeof,

>> -			   file->f_flags & O_DIRECT,

>> -			   (unsigned long)data & ~PAGE_MASK);

>> +		return ret;

>>  

>> -	if (ret >= 0 && (file->f_flags & O_DIRECT) == 0)

>> -		ret = ceph_copy_page_vector_to_user(pages, data, off, ret);

>> -	if (ret >= 0)

>> -		*poff = off + ret;

>> +	if (file->f_flags & O_DIRECT) {

>> +		while (iov_iter_count(i)) {

>> +			void __user *data = i->iov[0].iov_base + i->iov_offset;

>> +			size_t len = i->iov[0].iov_len - i->iov_offset;

>> +

>> +			num_pages = calc_pages_for((unsigned long)data, len);

>> +			pages = ceph_get_direct_page_vector(data,

>> +							    num_pages, true);

>> +			if (IS_ERR(pages))

>> +				return PTR_ERR(pages);

>> +

>> +			ret = striped_read(inode, off, len,

>> +					   pages, num_pages, checkeof,

>> +					   1, (unsigned long)data & ~PAGE_MASK);

>> +			ceph_put_page_vector(pages, num_pages, true);

>> +

>> +			if (ret <= 0)

>> +				break;

>> +			off += ret;

>

>iov_iter_advance(i, ret) should be here.

>

Yes, Thanks very much!
>Rest change looks good. After fixing this, you can add my reviewed-by to your patch

>

>Regards

>Yan, Zheng 

>

>> +			if (ret < len)

>> +				break;

>> +			iov_iter_advance(i, ret);

>> +		}

>> +	} else {

>> +		size_t len = iocb->ki_left;

>>  

>> -done:

>> -	if (file->f_flags & O_DIRECT)

>> -		ceph_put_page_vector(pages, num_pages, true);

>> -	else

>> +		num_pages = calc_pages_for(off, len);

>> +		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);

>> +		if (IS_ERR(pages))

>> +			return PTR_ERR(pages);

>> +		ret = striped_read(inode, off, len, pages,

>> +					num_pages, checkeof, 0, 0);

>> +		if (ret > 0) {

>> +			int l, k = 0;

>> +			size_t left = len = ret;

>> +

>> +			while (left) {

>> +				void __user *data = i->iov[0].iov_base

>> +							+ i->iov_offset;

>> +				l = min(i->iov[0].iov_len - i->iov_offset,

>> +					left);

>> +

>> +				ret = ceph_copy_page_vector_to_user(&pages[k],

>> +								    data, off,

>> +								    l);

>> +				if (ret > 0) {

>> +					iov_iter_advance(i, ret);

>> +					left -= ret;

>> +					off += ret;

>> +					k = calc_pages_for(iocb->ki_pos,

>> +							   len - left + 1) - 1;

>> +					BUG_ON(k >= num_pages && left);

>> +				} else

>> +					break;

>> +			}

>> +		}

>>  		ceph_release_page_vector(pages, num_pages);

>> +	}

>> +

>> +	if (off > iocb->ki_pos) {

>> +		ret = off - iocb->ki_pos;

>> +		iocb->ki_pos = off;

>> +		iocb->ki_left -= ret;

>> +	}

>> +

>>  	dout("sync_read result %d\n", ret);

>>  	return ret;

>>  }

>> @@ -647,55 +690,67 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,

>>  {

>>  	struct file *filp = iocb->ki_filp;

>>  	struct ceph_file_info *fi = filp->private_data;

>> -	loff_t *ppos = &iocb->ki_pos;

>> -	size_t len = iov->iov_len;

>> +	size_t len = 0;

>>  	struct inode *inode = file_inode(filp);

>>  	struct ceph_inode_info *ci = ceph_inode(inode);

>> -	void __user *base = iov->iov_base;

>>  	ssize_t ret;

>>  	int want, got = 0;

>>  	int checkeof = 0, read = 0;

>>  

>>  	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",

>>  	     inode, ceph_vinop(inode), pos, (unsigned)len, inode);

>> -again:

>> +

>> +	ret = generic_segment_checks(iov, &nr_segs, &len, VERIFY_WRITE);

>> +	if (ret)

>> +		return ret;

>> +

>>  	if (fi->fmode & CEPH_FILE_MODE_LAZY)

>>  		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;

>>  	else

>>  		want = CEPH_CAP_FILE_CACHE;

>>  	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);

>>  	if (ret < 0)

>> -		goto out;

>> +		return ret;

>> +

>>  	dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",

>>  	     inode, ceph_vinop(inode), pos, (unsigned)len,

>>  	     ceph_cap_string(got));

>>  

>>  	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||

>>  	    (iocb->ki_filp->f_flags & O_DIRECT) ||

>> -	    (fi->flags & CEPH_F_SYNC))

>> +	    (fi->flags & CEPH_F_SYNC)) {

>> +		struct iov_iter i;

>> +

>> +		iocb->ki_left = len;

>> +		iov_iter_init(&i, iov, nr_segs, len, 0);

>> +again:

>>  		/* hmm, this isn't really async... */

>> -		ret = ceph_sync_read(filp, base, len, ppos, &checkeof);

>> -	else

>> +		ret = ceph_sync_read(iocb, &i, &checkeof);

>> +

>> +		if (checkeof && ret >= 0) {

>> +			int statret = ceph_do_getattr(inode,

>> +						      CEPH_STAT_CAP_SIZE);

>> +

>> +			/* hit EOF or hole? */

>> +			if (statret == 0 && iocb->ki_pos < inode->i_size &&

>> +				iocb->ki_left) {

>> +				dout("sync_read hit hole, ppos %lld < size %lld"

>> +				     ", reading more\n", iocb->ki_pos,

>> +				     inode->i_size);

>> +

>> +				read += ret;

>> +				checkeof = 0;

>> +				goto again;

>> +			}

>> +		}

>> +

>> +	} else

>>  		ret = generic_file_aio_read(iocb, iov, nr_segs, pos);

>>  

>> -out:

>>  	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",

>>  	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);

>>  	ceph_put_cap_refs(ci, got);

>>  

>> -	if (checkeof && ret >= 0) {

>> -		int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);

>> -

>> -		/* hit EOF or hole? */

>> -		if (statret == 0 && *ppos < inode->i_size) {

>> -			dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size);

>> -			read += ret;

>> -			base += ret;

>> -			len -= ret;

>> -			checkeof = 0;

>> -			goto again;

>> -		}

>> -	}

>>  	if (ret >= 0)

>>  		ret += read;

>>  

>> 

>


Subject:  ceph: Implement readv/preadv for sync operation.

For readv/preadv sync-operatoin, ceph only do the first iov.
It don't think other iovs.Now implement this.

V3: 
   modify some bug.
V2:
  -add generic_segment_checks
  -using struct iov_iter replace cloning the iovs.
  -return previous successfully copied if ceph_copy_page_vector_to_user
   met error.


Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>

Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>

---
  fs/ceph/file.c | 157 ++++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 106 insertions(+), 51 deletions(-)

-- 
1.8.3
diff mbox

Patch

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 3de8982..bc7fa52 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -408,51 +408,94 @@  more:
  *
  * If the read spans object boundary, just do multiple reads.
  */
-static ssize_t ceph_sync_read(struct file *file, char __user *data,
-			      unsigned len, loff_t *poff, int *checkeof)
+static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
+				int *checkeof)
 {
+	struct file *file = iocb->ki_filp;
 	struct inode *inode = file_inode(file);
 	struct page **pages;
-	u64 off = *poff;
+	u64 off = iocb->ki_pos;
 	int num_pages, ret;
 
-	dout("sync_read on file %p %llu~%u %s\n", file, off, len,
+	dout("sync_read on file %p %llu~%u %s\n", file, off,
+	     (unsigned)iocb->ki_left,
 	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
-
-	if (file->f_flags & O_DIRECT) {
-		num_pages = calc_pages_for((unsigned long)data, len);
-		pages = ceph_get_direct_page_vector(data, num_pages, true);
-	} else {
-		num_pages = calc_pages_for(off, len);
-		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
-	}
-	if (IS_ERR(pages))
-		return PTR_ERR(pages);
-
 	/*
 	 * flush any page cache pages in this range.  this
 	 * will make concurrent normal and sync io slow,
 	 * but it will at least behave sensibly when they are
 	 * in sequence.
 	 */
-	ret = filemap_write_and_wait(inode->i_mapping);
+	ret = filemap_write_and_wait_range(inode->i_mapping, off,
+						off + iocb->ki_left);
 	if (ret < 0)
-		goto done;
-
-	ret = striped_read(inode, off, len, pages, num_pages, checkeof,
-			   file->f_flags & O_DIRECT,
-			   (unsigned long)data & ~PAGE_MASK);
+		return ret;
 
-	if (ret >= 0 && (file->f_flags & O_DIRECT) == 0)
-		ret = ceph_copy_page_vector_to_user(pages, data, off, ret);
-	if (ret >= 0)
-		*poff = off + ret;
+	if (file->f_flags & O_DIRECT) {
+		while (iov_iter_count(i)) {
+			void __user *data = i->iov[0].iov_base + i->iov_offset;
+			size_t len = i->iov[0].iov_len - i->iov_offset;
+
+			num_pages = calc_pages_for((unsigned long)data, len);
+			pages = ceph_get_direct_page_vector(data,
+							    num_pages, true);
+			if (IS_ERR(pages))
+				return PTR_ERR(pages);
+
+			ret = striped_read(inode, off, len,
+					   pages, num_pages, checkeof,
+					   1, (unsigned long)data & ~PAGE_MASK);
+			ceph_put_page_vector(pages, num_pages, true);
+
+			if (ret <= 0)
+				break;
+			off += ret;
+			iov_iter_advance(i, ret);
+			if (ret < len)
+				break;
+		}
+	} else {
+		size_t len = iocb->ki_left;
 
-done:
-	if (file->f_flags & O_DIRECT)
-		ceph_put_page_vector(pages, num_pages, true);
-	else
+		num_pages = calc_pages_for(off, len);
+		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
+		if (IS_ERR(pages))
+			return PTR_ERR(pages);
+		ret = striped_read(inode, off, len, pages,
+					num_pages, checkeof, 0, 0);
+		if (ret > 0) {
+			int l, k = 0;
+			size_t left = len = ret;
+
+			while (left) {
+				void __user *data = i->iov[0].iov_base
+							+ i->iov_offset;
+				l = min(i->iov[0].iov_len - i->iov_offset,
+					left);
+
+				ret = ceph_copy_page_vector_to_user(&pages[k],
+								    data, off,
+								    l);
+				if (ret > 0) {
+					iov_iter_advance(i, ret);
+					left -= ret;
+					off += ret;
+					k = calc_pages_for(iocb->ki_pos,
+							   len - left + 1) - 1;
+					BUG_ON(k >= num_pages && left);
+				} else
+					break;
+			}
+		}
 		ceph_release_page_vector(pages, num_pages);
+	}
+
+	if (off > iocb->ki_pos) {
+		ret = off - iocb->ki_pos;
+		iocb->ki_pos = off;
+		iocb->ki_left -= ret;
+	}
+
 	dout("sync_read result %d\n", ret);
 	return ret;
 }
@@ -647,55 +690,67 @@  static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct file *filp = iocb->ki_filp;
 	struct ceph_file_info *fi = filp->private_data;
-	loff_t *ppos = &iocb->ki_pos;
-	size_t len = iov->iov_len;
+	size_t len = 0;
 	struct inode *inode = file_inode(filp);
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	void __user *base = iov->iov_base;
 	ssize_t ret;
 	int want, got = 0;
 	int checkeof = 0, read = 0;
 
 	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
 	     inode, ceph_vinop(inode), pos, (unsigned)len, inode);
-again:
+
+	ret = generic_segment_checks(iov, &nr_segs, &len, VERIFY_WRITE);
+	if (ret)
+		return ret;
+
 	if (fi->fmode & CEPH_FILE_MODE_LAZY)
 		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
 	else
 		want = CEPH_CAP_FILE_CACHE;
 	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);
 	if (ret < 0)
-		goto out;
+		return ret;
+
 	dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
 	     inode, ceph_vinop(inode), pos, (unsigned)len,
 	     ceph_cap_string(got));
 
 	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
 	    (iocb->ki_filp->f_flags & O_DIRECT) ||
-	    (fi->flags & CEPH_F_SYNC))
+	    (fi->flags & CEPH_F_SYNC)) {
+		struct iov_iter i;
+
+		iocb->ki_left = len;
+		iov_iter_init(&i, iov, nr_segs, len, 0);
+again:
 		/* hmm, this isn't really async... */
-		ret = ceph_sync_read(filp, base, len, ppos, &checkeof);
-	else
+		ret = ceph_sync_read(iocb, &i, &checkeof);
+
+		if (checkeof && ret >= 0) {
+			int statret = ceph_do_getattr(inode,
+						      CEPH_STAT_CAP_SIZE);
+
+			/* hit EOF or hole? */
+			if (statret == 0 && iocb->ki_pos < inode->i_size &&
+				iocb->ki_left) {
+				dout("sync_read hit hole, ppos %lld < size %lld"
+				     ", reading more\n", iocb->ki_pos,
+				     inode->i_size);
+
+				read += ret;
+				checkeof = 0;
+				goto again;
+			}
+		}
+
+	} else
 		ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
 
-out:
 	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
 	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
 	ceph_put_cap_refs(ci, got);
 
-	if (checkeof && ret >= 0) {
-		int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
-
-		/* hit EOF or hole? */
-		if (statret == 0 && *ppos < inode->i_size) {
-			dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size);
-			read += ret;
-			base += ret;
-			len -= ret;
-			checkeof = 0;
-			goto again;
-		}
-	}
 	if (ret >= 0)
 		ret += read;