ocfs2: implement ocfs2_direct_IO_write
authorJoseph Qi <joseph.qi@huawei.com>
Tue, 17 Feb 2015 00:00:00 +0000 (16:00 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 17 Feb 2015 01:56:05 +0000 (17:56 -0800)
Implement ocfs2_direct_IO_write.  Add the inode to orphan dir first, and
then delete it once append O_DIRECT finished.

This is to make sure block allocation and inode size are consistent.

[akpm@linux-foundation.org: fix it for "block: Add discard flag to blkdev_issue_zeroout() function"]
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Weiwei Wang <wangww631@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Xuejiufei <xuejiufei@huawei.com>
Cc: alex chen <alex.chen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ocfs2/aops.c
fs/ocfs2/ocfs2.h

index 46d93e9..be5986b 100644 (file)
@@ -28,6 +28,7 @@
 #include <linux/pipe_fs_i.h>
 #include <linux/mpage.h>
 #include <linux/quotaops.h>
+#include <linux/blkdev.h>
 
 #include <cluster/masklog.h>
 
@@ -47,6 +48,9 @@
 #include "ocfs2_trace.h"
 
 #include "buffer_head_io.h"
+#include "dir.h"
+#include "namei.h"
+#include "sysfile.h"
 
 static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
                                   struct buffer_head *bh_result, int create)
@@ -597,6 +601,184 @@ static int ocfs2_releasepage(struct page *page, gfp_t wait)
        return try_to_free_buffers(page);
 }
 
+static int ocfs2_is_overwrite(struct ocfs2_super *osb,
+               struct inode *inode, loff_t offset)
+{
+       int ret = 0;
+       u32 v_cpos = 0;
+       u32 p_cpos = 0;
+       unsigned int num_clusters = 0;
+       unsigned int ext_flags = 0;
+
+       v_cpos = ocfs2_bytes_to_clusters(osb->sb, offset);
+       ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos,
+                       &num_clusters, &ext_flags);
+       if (ret < 0) {
+               mlog_errno(ret);
+               return ret;
+       }
+
+       if (p_cpos && !(ext_flags & OCFS2_EXT_UNWRITTEN))
+               return 1;
+
+       return 0;
+}
+
+static ssize_t ocfs2_direct_IO_write(struct kiocb *iocb,
+               struct iov_iter *iter,
+               loff_t offset)
+{
+       ssize_t ret = 0;
+       ssize_t written = 0;
+       bool orphaned = false;
+       int is_overwrite = 0;
+       struct file *file = iocb->ki_filp;
+       struct inode *inode = file_inode(file)->i_mapping->host;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       struct buffer_head *di_bh = NULL;
+       size_t count = iter->count;
+       journal_t *journal = osb->journal->j_journal;
+       u32 zero_len;
+       int cluster_align;
+       loff_t final_size = offset + count;
+       int append_write = offset >= i_size_read(inode) ? 1 : 0;
+       unsigned int num_clusters = 0;
+       unsigned int ext_flags = 0;
+
+       {
+               u64 o = offset;
+
+               zero_len = do_div(o, 1 << osb->s_clustersize_bits);
+               cluster_align = !zero_len;
+       }
+
+       /*
+        * when final_size > inode->i_size, inode->i_size will be
+        * updated after direct write, so add the inode to orphan
+        * dir first.
+        */
+       if (final_size > i_size_read(inode)) {
+               ret = ocfs2_add_inode_to_orphan(osb, inode);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       goto out;
+               }
+               orphaned = true;
+       }
+
+       if (append_write) {
+               ret = ocfs2_inode_lock(inode, &di_bh, 1);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       goto clean_orphan;
+               }
+
+               if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
+                       ret = ocfs2_zero_extend(inode, di_bh, offset);
+               else
+                       ret = ocfs2_extend_no_holes(inode, di_bh, offset,
+                                       offset);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       ocfs2_inode_unlock(inode, 1);
+                       brelse(di_bh);
+                       goto clean_orphan;
+               }
+
+               is_overwrite = ocfs2_is_overwrite(osb, inode, offset);
+               if (is_overwrite < 0) {
+                       mlog_errno(is_overwrite);
+                       ocfs2_inode_unlock(inode, 1);
+                       brelse(di_bh);
+                       goto clean_orphan;
+               }
+
+               ocfs2_inode_unlock(inode, 1);
+               brelse(di_bh);
+               di_bh = NULL;
+       }
+
+       written = __blockdev_direct_IO(WRITE, iocb, inode, inode->i_sb->s_bdev,
+                       iter, offset,
+                       ocfs2_direct_IO_get_blocks,
+                       ocfs2_dio_end_io, NULL, 0);
+       if (unlikely(written < 0)) {
+               loff_t i_size = i_size_read(inode);
+
+               if (offset + count > i_size) {
+                       ret = ocfs2_inode_lock(inode, &di_bh, 1);
+                       if (ret < 0) {
+                               mlog_errno(ret);
+                               goto clean_orphan;
+                       }
+
+                       if (i_size == i_size_read(inode)) {
+                               ret = ocfs2_truncate_file(inode, di_bh,
+                                               i_size);
+                               if (ret < 0) {
+                                       if (ret != -ENOSPC)
+                                               mlog_errno(ret);
+
+                                       ocfs2_inode_unlock(inode, 1);
+                                       brelse(di_bh);
+                                       goto clean_orphan;
+                               }
+                       }
+
+                       ocfs2_inode_unlock(inode, 1);
+                       brelse(di_bh);
+
+                       ret = jbd2_journal_force_commit(journal);
+                       if (ret < 0)
+                               mlog_errno(ret);
+               }
+       } else if (written < 0 && append_write && !is_overwrite &&
+                       !cluster_align) {
+               u32 p_cpos = 0;
+               u32 v_cpos = ocfs2_bytes_to_clusters(osb->sb, offset);
+
+               ret = ocfs2_get_clusters(inode, v_cpos, &p_cpos,
+                               &num_clusters, &ext_flags);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       goto clean_orphan;
+               }
+
+               BUG_ON(!p_cpos || (ext_flags & OCFS2_EXT_UNWRITTEN));
+
+               ret = blkdev_issue_zeroout(osb->sb->s_bdev,
+                               p_cpos << (osb->s_clustersize_bits - 9),
+                               zero_len >> 9, GFP_KERNEL, false);
+               if (ret < 0)
+                       mlog_errno(ret);
+       }
+
+clean_orphan:
+       if (orphaned) {
+               int tmp_ret;
+               int update_isize = written > 0 ? 1 : 0;
+               loff_t end = update_isize ? offset + written : 0;
+
+               tmp_ret = ocfs2_del_inode_from_orphan(osb, inode,
+                               update_isize, end);
+               if (tmp_ret < 0) {
+                       ret = tmp_ret;
+                       goto out;
+               }
+
+               tmp_ret = jbd2_journal_force_commit(journal);
+               if (tmp_ret < 0) {
+                       ret = tmp_ret;
+                       mlog_errno(tmp_ret);
+               }
+       }
+
+out:
+       if (ret >= 0)
+               ret = written;
+       return ret;
+}
+
 static ssize_t ocfs2_direct_IO(int rw,
                               struct kiocb *iocb,
                               struct iov_iter *iter,
@@ -604,6 +786,9 @@ static ssize_t ocfs2_direct_IO(int rw,
 {
        struct file *file = iocb->ki_filp;
        struct inode *inode = file_inode(file)->i_mapping->host;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       int full_coherency = !(osb->s_mount_opt &
+                       OCFS2_MOUNT_COHERENCY_BUFFERED);
 
        /*
         * Fallback to buffered I/O if we see an inode without
@@ -612,14 +797,20 @@ static ssize_t ocfs2_direct_IO(int rw,
        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)
+       /* Fallback to buffered I/O if we are appending and
+        * concurrent O_DIRECT writes are allowed.
+        */
+       if (i_size_read(inode) <= offset && !full_coherency)
                return 0;
 
-       return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev,
+       if (rw == READ)
+               return __blockdev_direct_IO(rw, iocb, inode,
+                                   inode->i_sb->s_bdev,
                                    iter, offset,
                                    ocfs2_direct_IO_get_blocks,
                                    ocfs2_dio_end_io, NULL, 0);
+       else
+               return ocfs2_direct_IO_write(iocb, iter, offset);
 }
 
 static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
index df9a95c..7e39cd6 100644 (file)
@@ -731,6 +731,16 @@ static inline unsigned int ocfs2_clusters_for_bytes(struct super_block *sb,
        return clusters;
 }
 
+static inline unsigned int ocfs2_bytes_to_clusters(struct super_block *sb,
+               u64 bytes)
+{
+       int cl_bits = OCFS2_SB(sb)->s_clustersize_bits;
+       unsigned int clusters;
+
+       clusters = (unsigned int)(bytes >> cl_bits);
+       return clusters;
+}
+
 static inline u64 ocfs2_blocks_for_bytes(struct super_block *sb,
                                         u64 bytes)
 {