[PATCH] VFS: pass file pointer to filesystem from ftruncate()
This patch extends the iattr structure with a file pointer memeber, and adds
an ATTR_FILE validity flag for this member.
This is set if do_truncate() is invoked from ftruncate() or from
do_coredump().
The change is source and binary compatible.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/exec.c b/fs/exec.c
index ce76b33..cd6c574 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1511,7 +1511,7 @@
goto close_fail;
if (!file->f_op->write)
goto close_fail;
- if (do_truncate(file->f_dentry, 0) != 0)
+ if (do_truncate(file->f_dentry, 0, file) != 0)
goto close_fail;
retval = binfmt->core_dump(signr, regs, file);
diff --git a/fs/namei.c b/fs/namei.c
index c5769c4..b3f8a19 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1459,7 +1459,7 @@
if (!error) {
DQUOT_INIT(inode);
- error = do_truncate(dentry, 0);
+ error = do_truncate(dentry, 0, NULL);
}
put_write_access(inode);
if (error)
diff --git a/fs/open.c b/fs/open.c
index 2835f09..6e81367 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -194,7 +194,7 @@
return error;
}
-int do_truncate(struct dentry *dentry, loff_t length)
+int do_truncate(struct dentry *dentry, loff_t length, struct file *filp)
{
int err;
struct iattr newattrs;
@@ -205,6 +205,10 @@
newattrs.ia_size = length;
newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
+ if (filp) {
+ newattrs.ia_file = filp;
+ newattrs.ia_valid |= ATTR_FILE;
+ }
down(&dentry->d_inode->i_sem);
err = notify_change(dentry, &newattrs);
@@ -262,7 +266,7 @@
error = locks_verify_truncate(inode, NULL, length);
if (!error) {
DQUOT_INIT(inode);
- error = do_truncate(nd.dentry, length);
+ error = do_truncate(nd.dentry, length, NULL);
}
put_write_access(inode);
@@ -314,7 +318,7 @@
error = locks_verify_truncate(inode, file, length);
if (!error)
- error = do_truncate(dentry, length);
+ error = do_truncate(dentry, length, file);
out_putf:
fput(file);
out:
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 6d62267..0c89fc9 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -264,6 +264,7 @@
#define ATTR_ATTR_FLAG 1024
#define ATTR_KILL_SUID 2048
#define ATTR_KILL_SGID 4096
+#define ATTR_FILE 8192
/*
* This is the Inode Attributes structure, used for notify_change(). It
@@ -283,6 +284,13 @@
struct timespec ia_atime;
struct timespec ia_mtime;
struct timespec ia_ctime;
+
+ /*
+ * Not an attribute, but an auxilary info for filesystems wanting to
+ * implement an ftruncate() like method. NOTE: filesystem should
+ * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
+ */
+ struct file *ia_file;
};
/*
@@ -1288,7 +1296,7 @@
/* fs/open.c */
-extern int do_truncate(struct dentry *, loff_t start);
+extern int do_truncate(struct dentry *, loff_t start, struct file *filp);
extern long do_sys_open(const char __user *filename, int flags, int mode);
extern struct file *filp_open(const char *, int, int);
extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);