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authorTao Ma <tao.ma@oracle.com>2009-08-25 08:02:48 +0800
committerJoel Becker <joel.becker@oracle.com>2009-09-22 20:09:37 -0700
commit293b2f70b4a16a1ca91efd28ef3d6634262c6887 (patch)
tree4a85078faae7c529fa313d4964e0d6ad0905a612 /fs
parent6ae23c5555176c5b23480c9c578ff27437085ba5 (diff)
downloadop-kernel-dev-293b2f70b4a16a1ca91efd28ef3d6634262c6887.zip
op-kernel-dev-293b2f70b4a16a1ca91efd28ef3d6634262c6887.tar.gz
ocfs2: Integrate CoW in file write.
When we use mmap, we CoW the refcountd clusters in ocfs2_write_begin_nolock. While for normal file io(including directio), we do CoW in ocfs2_prepare_inode_for_write. Signed-off-by: Tao Ma <tao.ma@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/ocfs2/aops.c19
-rw-r--r--fs/ocfs2/file.c84
-rw-r--r--fs/ocfs2/file.h2
3 files changed, 104 insertions, 1 deletions
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index fdad075..9db9d64 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -44,6 +44,7 @@
#include "suballoc.h"
#include "super.h"
#include "symlink.h"
+#include "refcounttree.h"
#include "buffer_head_io.h"
@@ -590,6 +591,8 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
goto bail;
}
+ /* We should already CoW the refcounted extent. */
+ BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
/*
* get_more_blocks() expects us to describe a hole by clearing
* the mapped bit on bh_result().
@@ -1449,6 +1452,9 @@ static int ocfs2_populate_write_desc(struct inode *inode,
goto out;
}
+ /* We should already CoW the refcountd extent. */
+ BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
+
/*
* Assume worst case - that we're writing in
* the middle of the extent.
@@ -1700,6 +1706,19 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
goto out;
}
+ ret = ocfs2_check_range_for_refcount(inode, pos, len);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ } else if (ret == 1) {
+ ret = ocfs2_refcount_cow(inode, di_bh,
+ wc->w_cpos, wc->w_clen);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc,
&extents_to_split);
if (ret) {
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 4921b4e..6ee20e8 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -59,6 +59,7 @@
#include "xattr.h"
#include "acl.h"
#include "quota.h"
+#include "refcounttree.h"
#include "buffer_head_io.h"
@@ -1656,6 +1657,70 @@ static long ocfs2_fallocate(struct inode *inode, int mode, loff_t offset,
OCFS2_IOC_RESVSP64, &sr, change_size);
}
+int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
+ size_t count)
+{
+ int ret = 0;
+ unsigned int extent_flags;
+ u32 cpos, clusters, extent_len, phys_cpos;
+ struct super_block *sb = inode->i_sb;
+
+ if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb)) ||
+ !(OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL))
+ return 0;
+
+ cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
+ clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
+
+ while (clusters) {
+ ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
+ &extent_flags);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (phys_cpos && (extent_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = 1;
+ break;
+ }
+
+ if (extent_len > clusters)
+ extent_len = clusters;
+
+ clusters -= extent_len;
+ cpos += extent_len;
+ }
+out:
+ return ret;
+}
+
+static int ocfs2_prepare_inode_for_refcount(struct inode *inode,
+ loff_t pos, size_t count,
+ int *meta_level)
+{
+ int ret;
+ struct buffer_head *di_bh = NULL;
+ u32 cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
+ u32 clusters =
+ ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ *meta_level = 1;
+
+ ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters);
+ if (ret)
+ mlog_errno(ret);
+out:
+ brelse(di_bh);
+ return ret;
+}
+
static int ocfs2_prepare_inode_for_write(struct dentry *dentry,
loff_t *ppos,
size_t count,
@@ -1712,6 +1777,22 @@ static int ocfs2_prepare_inode_for_write(struct dentry *dentry,
end = saved_pos + count;
+ ret = ocfs2_check_range_for_refcount(inode, saved_pos, count);
+ if (ret == 1) {
+ ocfs2_inode_unlock(inode, meta_level);
+ meta_level = -1;
+
+ ret = ocfs2_prepare_inode_for_refcount(inode,
+ saved_pos,
+ count,
+ &meta_level);
+ }
+
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
/*
* Skip the O_DIRECT checks if we don't need
* them.
@@ -1758,7 +1839,8 @@ static int ocfs2_prepare_inode_for_write(struct dentry *dentry,
*ppos = saved_pos;
out_unlock:
- ocfs2_inode_unlock(inode, meta_level);
+ if (meta_level >= 0)
+ ocfs2_inode_unlock(inode, meta_level);
out:
return ret;
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 172f9fb..d66cf4f 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -69,4 +69,6 @@ int ocfs2_update_inode_atime(struct inode *inode,
int ocfs2_change_file_space(struct file *file, unsigned int cmd,
struct ocfs2_space_resv *sr);
+int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
+ size_t count);
#endif /* OCFS2_FILE_H */
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