[JFFS2] Use ALLOC_DELETION priority for truncation to zero length

This is going to obsolete all previous nodes, so treat it as deletion.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 3f49562dc508..9dafb53fb1d1 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -36,6 +36,7 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
         unsigned int ivalid;
         uint32_t alloclen;
         int ret;
+        int alloc_type = ALLOC_NORMAL;
 
         D1(printk(KERN_DEBUG "jffs2_setattr(): ino #%lu\n", inode->i_ino));
 
@@ -115,6 +116,10 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
                 ri->compr = JFFS2_COMPR_ZERO;
                 ri->dsize = cpu_to_je32(iattr->ia_size - inode->i_size);
                 ri->offset = cpu_to_je32(inode->i_size);
+        } else if (ivalid & ATTR_SIZE && !iattr->ia_size) {
+                /* For truncate-to-zero, treat it as deletion because
+                   it'll always be obsoleting all previous nodes */
+                alloc_type = ALLOC_DELETION;
         }
         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
         if (mdatalen)
@@ -122,7 +127,7 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
         else
                 ri->data_crc = cpu_to_je32(0);
 
-        new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, ALLOC_NORMAL);
+        new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, alloc_type);
         if (S_ISLNK(inode->i_mode))
                 kfree(mdata);