new helper: __alloc_fd()
Essentially, alloc_fd() in a files_struct we own a reference to.
Most of the time wanting to use it is a sign of lousy API
design (such as android/binder). It's *not* a general-purpose
interface; better that than open-coding its guts, but again,
playing with other process' descriptor table is a sign of bad
design.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/file.c b/fs/file.c
index 08922af..a3a0705 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -420,11 +420,10 @@
/*
* allocate a file descriptor, mark it busy.
*/
-int alloc_fd(unsigned start, unsigned flags)
+int __alloc_fd(struct files_struct *files,
+ unsigned start, unsigned end, unsigned flags)
{
- struct files_struct *files = current->files;
unsigned int fd;
- unsigned end = rlimit(RLIMIT_NOFILE);
int error;
struct fdtable *fdt;
@@ -479,8 +478,13 @@
return error;
}
+int alloc_fd(unsigned start, unsigned flags)
+{
+ return __alloc_fd(current->files, start, rlimit(RLIMIT_NOFILE), flags);
+}
+
int get_unused_fd_flags(unsigned flags)
{
- return alloc_fd(0, flags);
+ return __alloc_fd(current->files, 0, rlimit(RLIMIT_NOFILE), flags);
}
EXPORT_SYMBOL(get_unused_fd_flags);