The function __close_fd was added to support binder[1]. Now that
binder has been fixed to no longer need __close_fd[2] all calls
to __close_fd pass current->files.
Therefore transform the files parameter into a local variable
initialized to current->files, and rename __close_fd to close_fd to
reflect this change, and keep it in sync with the similar changes to
__alloc_fd, and __fd_install.
This removes the need for callers to care about the extra care that
needs to be take if anything except current->files is passed, by
limiting the callers to only operation on current->files.
[1] 483ce1d4b8c3 ("take descriptor-related part of close() to file.c")
[2] 44d8047f1d87 ("binder: use standard functions to allocate fds")
Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
v1: https://lkml.kernel.org/r/20200817220425.9389-17-ebiederm@xxxxxxxxxxxx
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
---
fs/file.c | 10 ++++------
fs/open.c | 2 +-
include/linux/fdtable.h | 3 +--
include/linux/syscalls.h | 6 +++---
4 files changed, 9 insertions(+), 12 deletions(-)
diff --git a/fs/file.c b/fs/file.c
index 621563701bd9..987ea51630b4 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -629,11 +629,9 @@ static struct file *pick_file(struct files_struct *files, unsigned fd)
return file;
}
-/*
- * The same warnings as for __alloc_fd()/__fd_install() apply here...
- */
-int __close_fd(struct files_struct *files, unsigned fd)
+int close_fd(unsigned fd)
{
+ struct files_struct *files = current->files;
struct file *file;
file = pick_file(files, fd);
@@ -642,7 +640,7 @@ int __close_fd(struct files_struct *files, unsigned fd)
return filp_close(file, files);
}
-EXPORT_SYMBOL(__close_fd); /* for ksys_close() */
+EXPORT_SYMBOL(close_fd); /* for ksys_close() */
/**
* __close_range() - Close all file descriptors in a given range.
@@ -1027,7 +1025,7 @@ int replace_fd(unsigned fd, struct file *file, unsigned flags)
struct files_struct *files = current->files;
if (!file)
- return __close_fd(files, fd);
+ return close_fd(fd);
if (fd >= rlimit(RLIMIT_NOFILE))
return -EBADF;
diff --git a/fs/open.c b/fs/open.c
index 9af548fb841b..581a674d7eee 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -1292,7 +1292,7 @@ EXPORT_SYMBOL(filp_close);
*/
SYSCALL_DEFINE1(close, unsigned int, fd)
{
- int retval = __close_fd(current->files, fd);
+ int retval = close_fd(fd);
/* can't restart close syscall because file table entry was cleared */
if (unlikely(retval == -ERESTARTSYS ||
diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h
index dc476ae92f56..dad4a488ce60 100644
--- a/include/linux/fdtable.h
+++ b/include/linux/fdtable.h
@@ -124,8 +124,7 @@ int iterate_fd(struct files_struct *, unsigned,
int (*)(const void *, struct file *, unsigned),
const void *);
-extern int __close_fd(struct files_struct *files,
- unsigned int fd);
+extern int close_fd(unsigned int fd);
extern int __close_range(unsigned int fd, unsigned int max_fd, unsigned int flags);
extern int __close_fd_get_file(unsigned int fd, struct file **res);
extern int unshare_fd(unsigned long unshare_flags, unsigned int max_fds,
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 37bea07c12f2..9e055a0579f8 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -1295,16 +1295,16 @@ static inline long ksys_ftruncate(unsigned int fd, loff_t length)
return do_sys_ftruncate(fd, length, 1);
}
-extern int __close_fd(struct files_struct *files, unsigned int fd);
+extern int close_fd(unsigned int fd);
/*
* In contrast to sys_close(), this stub does not check whether the syscall
* should or should not be restarted, but returns the raw error codes from
- * __close_fd().
+ * close_fd().
*/
static inline int ksys_close(unsigned int fd)
{
- return __close_fd(current->files, fd);
+ return close_fd(fd);
}
extern long do_sys_truncate(const char __user *pathname, loff_t length);
--
2.25.0
