Gang He
2017-Dec-28 10:07 UTC
[Ocfs2-devel] [PATCH v3 2/3] ocfs2: add ocfs2_overwrite_io function
Add ocfs2_overwrite_io function, which is used to judge if
overwrite allocated blocks, otherwise, the write will bring extra
block allocation overhead.
Signed-off-by: Gang He <ghe at suse.com>
---
fs/ocfs2/extent_map.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
fs/ocfs2/extent_map.h | 3 +++
2 files changed, 48 insertions(+)
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index e4719e0..06cb964 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -38,6 +38,7 @@
#include "inode.h"
#include "super.h"
#include "symlink.h"
+#include "aops.h"
#include "ocfs2_trace.h"
#include "buffer_head_io.h"
@@ -832,6 +833,50 @@ int ocfs2_fiemap(struct inode *inode, struct
fiemap_extent_info *fieinfo,
return ret;
}
+/* Is IO overwriting allocated blocks? */
+int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh,
+ u64 map_start, u64 map_len)
+{
+ int ret = 0, is_last;
+ u32 mapping_end, cpos;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_extent_rec rec;
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len))
+ return ret;
+ else
+ return -EAGAIN;
+ }
+
+ cpos = map_start >> osb->s_clustersize_bits;
+ mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
+ map_start + map_len);
+ is_last = 0;
+ while (cpos < mapping_end && !is_last) {
+ ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos,
+ NULL, &rec, &is_last);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (rec.e_blkno == 0ULL)
+ break;
+
+ if (rec.e_flags & OCFS2_EXT_REFCOUNTED)
+ break;
+
+ cpos = le32_to_cpu(rec.e_cpos) +
+ le16_to_cpu(rec.e_leaf_clusters);
+ }
+
+ if (cpos < mapping_end)
+ ret = -EAGAIN;
+out:
+ return ret;
+}
+
int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int whence)
{
struct inode *inode = file->f_mapping->host;
diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h
index 67ea57d..1057586 100644
--- a/fs/ocfs2/extent_map.h
+++ b/fs/ocfs2/extent_map.h
@@ -53,6 +53,9 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64
v_blkno, u64 *p_blkno,
int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 map_start, u64 map_len);
+int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh,
+ u64 map_start, u64 map_len);
+
int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int origin);
int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster,
--
1.8.5.6
alex chen
2018-Jan-02 11:00 UTC
[Ocfs2-devel] [PATCH v3 2/3] ocfs2: add ocfs2_overwrite_io function
Hi Gang, On 2017/12/28 18:07, Gang He wrote:> Add ocfs2_overwrite_io function, which is used to judge if > overwrite allocated blocks, otherwise, the write will bring extra > block allocation overhead. > > Signed-off-by: Gang He <ghe at suse.com> > --- > fs/ocfs2/extent_map.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ > fs/ocfs2/extent_map.h | 3 +++ > 2 files changed, 48 insertions(+) > > diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c > index e4719e0..06cb964 100644 > --- a/fs/ocfs2/extent_map.c > +++ b/fs/ocfs2/extent_map.c > @@ -38,6 +38,7 @@ > #include "inode.h" > #include "super.h" > #include "symlink.h" > +#include "aops.h" > #include "ocfs2_trace.h" > > #include "buffer_head_io.h" > @@ -832,6 +833,50 @@ int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > return ret; > } > > +/* Is IO overwriting allocated blocks? */ > +int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh, > + u64 map_start, u64 map_len)Here can the type of 'map_start' is struct loff_t and map_len is struct size_t? Thanks, Alex> +{ > + int ret = 0, is_last; > + u32 mapping_end, cpos; > + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); > + struct ocfs2_extent_rec rec; > + > + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) { > + if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len)) > + return ret; > + else > + return -EAGAIN; > + } > + > + cpos = map_start >> osb->s_clustersize_bits; > + mapping_end = ocfs2_clusters_for_bytes(inode->i_sb, > + map_start + map_len); > + is_last = 0; > + while (cpos < mapping_end && !is_last) { > + ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos, > + NULL, &rec, &is_last); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > + if (rec.e_blkno == 0ULL) > + break; > + > + if (rec.e_flags & OCFS2_EXT_REFCOUNTED) > + break; > + > + cpos = le32_to_cpu(rec.e_cpos) + > + le16_to_cpu(rec.e_leaf_clusters); > + } > + > + if (cpos < mapping_end) > + ret = -EAGAIN; > +out: > + return ret; > +} > + > int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int whence) > { > struct inode *inode = file->f_mapping->host; > diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h > index 67ea57d..1057586 100644 > --- a/fs/ocfs2/extent_map.h > +++ b/fs/ocfs2/extent_map.h > @@ -53,6 +53,9 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno, > int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > u64 map_start, u64 map_len); > > +int ocfs2_overwrite_io(struct inode *inode, struct buffer_head *di_bh, > + u64 map_start, u64 map_len); > + > int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int origin); > > int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster, >