[PATCH 08/30] smb/client: sort ntstatus_to_dos_map array

[chenxiaosong.chenxiaosong@linux.dev]

From: ChenXiaoSong <chenxiaosong@kylinos.cn>

Sort the array in ascending order, and then we can use binary search
algorithm to quickly find the target NT error code.

The array is sorted only once in smb1_init_maperror() when cifs.ko
is loaded.

Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
---
 fs/smb/client/cifsfs.c    |  2 ++
 fs/smb/client/cifsproto.h |  1 +
 fs/smb/client/netmisc.c   | 20 ++++++++++++++++++--
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index 77d14b3dd650..3e3affce585e 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -49,6 +49,7 @@
 #endif
 #include "fs_context.h"
 #include "cached_dir.h"
+#include "cifsproto.h"
 #include "smb2proto.h"
 
 /*
@@ -1909,6 +1910,7 @@ static int __init
 init_cifs(void)
 {
 	int rc = 0;
+	smb_init_maperror();
 	smb2_init_maperror();
 	cifs_proc_init();
 	INIT_LIST_HEAD(&cifs_tcp_ses_list);
diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h
index 3528c365a452..675413d701b3 100644
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -188,6 +188,7 @@ extern int cifs_convert_address(struct sockaddr *dst, const char *src, int len);
 extern void cifs_set_port(struct sockaddr *addr, const unsigned short int port);
 extern int map_smb_to_linux_error(char *buf, bool logErr);
 extern int map_and_check_smb_error(struct mid_q_entry *mid, bool logErr);
+extern void smb_init_maperror(void);
 extern void header_assemble(struct smb_hdr *, char /* command */ ,
 			    const struct cifs_tcon *, int /* length of
 			    fixed section (word count) in two byte units */);
diff --git a/fs/smb/client/netmisc.c b/fs/smb/client/netmisc.c
index 73c40ae91607..54ede1db2c7f 100644
--- a/fs/smb/client/netmisc.c
+++ b/fs/smb/client/netmisc.c
@@ -16,6 +16,7 @@
 #include <asm/div64.h>
 #include <asm/byteorder.h>
 #include <linux/inet.h>
+#include <linux/sort.h>
 #include "cifsfs.h"
 #include "cifspdu.h"
 #include "cifsglob.h"
@@ -216,11 +217,13 @@ cifs_set_port(struct sockaddr *addr, const unsigned short int port)
 convert a NT status code to a dos class/code
  *****************************************************************************/
 /* NT status -> dos error map */
-static const struct {
+struct ntstatus_to_dos {
 	__u8 dos_class;
 	__u16 dos_code;
 	__u32 ntstatus;
-} ntstatus_to_dos_map[] = {
+};
+
+static struct ntstatus_to_dos ntstatus_to_dos_map[] = {
 	{
 	ERRDOS, ERRgeneral, NT_STATUS_UNSUCCESSFUL}, {
 	ERRDOS, ERRbadfunc, NT_STATUS_NOT_IMPLEMENTED}, {
@@ -778,6 +781,12 @@ static const struct {
 	0, 0, 0 }
 };
 
+static unsigned int ntstatus_to_dos_num = sizeof(ntstatus_to_dos_map) /
+					  sizeof(struct ntstatus_to_dos);
+
+/* cmp_ntstatus_to_dos */
+DEFINE_CMP_FUNC(ntstatus_to_dos, ntstatus);
+
 /*****************************************************************************
  Print an error message from the status code
  *****************************************************************************/
@@ -1040,3 +1049,10 @@ struct timespec64 cnvrtDosUnixTm(__le16 le_date, __le16 le_time, int offset)
 	ts.tv_nsec = 0;
 	return ts;
 }
+
+void smb_init_maperror(void)
+{
+	/* Sort in ascending order */
+	sort(ntstatus_to_dos_map, ntstatus_to_dos_num,
+	     sizeof(struct ntstatus_to_dos), cmp_ntstatus_to_dos, NULL);
+}
-- 
2.43.0