cache the value of file_inode() in struct file

Note that this thing does *not* contribute to inode refcount;
it's pinned down by dentry.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2013-03-01 19:48:30 -05:00
parent 5e608671df
commit dd37978c50
3 changed files with 6 additions and 2 deletions

View File

@ -176,6 +176,7 @@ struct file *alloc_file(struct path *path, fmode_t mode,
return file;
file->f_path = *path;
file->f_inode = path->dentry->d_inode;
file->f_mapping = path->dentry->d_inode->i_mapping;
file->f_mode = mode;
file->f_op = fop;
@ -258,6 +259,7 @@ static void __fput(struct file *file)
drop_file_write_access(file);
file->f_path.dentry = NULL;
file->f_path.mnt = NULL;
file->f_inode = NULL;
file_free(file);
dput(dentry);
mntput(mnt);

View File

@ -689,7 +689,7 @@ static int do_dentry_open(struct file *f,
f->f_mode = FMODE_PATH;
path_get(&f->f_path);
inode = file_inode(f);
inode = f->f_inode = f->f_path.dentry->d_inode;
if (f->f_mode & FMODE_WRITE) {
error = __get_file_write_access(inode, f->f_path.mnt);
if (error)
@ -752,6 +752,7 @@ cleanup_file:
path_put(&f->f_path);
f->f_path.mnt = NULL;
f->f_path.dentry = NULL;
f->f_inode = NULL;
return error;
}

View File

@ -769,6 +769,7 @@ struct file {
} f_u;
struct path f_path;
#define f_dentry f_path.dentry
struct inode *f_inode; /* cached value */
const struct file_operations *f_op;
/*
@ -2217,7 +2218,7 @@ static inline bool execute_ok(struct inode *inode)
static inline struct inode *file_inode(struct file *f)
{
return f->f_path.dentry->d_inode;
return f->f_inode;
}
/*