[PATCH v2 3/3] staging: exfat: add millisecond support

From: Valentin Vidic
Date: Sun Sep 08 2019 - 12:11:00 EST


Use create_time_ms modify_time_ms fields to store the millisecond
part of the file timestamp with the precision of 10 ms.

Signed-off-by: Valentin Vidic <vvidic@xxxxxxxxxxxxxxxxxxxxxx>
---
drivers/staging/exfat/exfat_core.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
index 8476eeedba83..e87119fa8c0a 100644
--- a/drivers/staging/exfat/exfat_core.c
+++ b/drivers/staging/exfat/exfat_core.c
@@ -1139,6 +1139,7 @@ void exfat_set_entry_size(struct dentry_t *p_entry, u64 size)
void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
u8 mode)
{
+ u8 ms = 0;
u16 t = 0x00, d = 0x21;
struct dos_dentry_t *ep = (struct dos_dentry_t *)p_entry;

@@ -1146,6 +1147,7 @@ void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
case TM_CREATE:
t = GET16_A(ep->create_time);
d = GET16_A(ep->create_date);
+ ms = ep->create_time_ms * 10;
break;
case TM_MODIFY:
t = GET16_A(ep->modify_time);
@@ -1159,11 +1161,17 @@ void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
tp->day = (d & 0x001F);
tp->mon = (d >> 5) & 0x000F;
tp->year = (d >> 9);
+
+ if (ms >= 1000) {
+ ms -= 1000;
+ tp->sec++;
+ }
}

void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
u8 mode)
{
+ u8 ms = 0;
u16 t = 0x00, d = 0x21;
struct file_dentry_t *ep = (struct file_dentry_t *)p_entry;

@@ -1171,10 +1179,12 @@ void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
case TM_CREATE:
t = GET16_A(ep->create_time);
d = GET16_A(ep->create_date);
+ ms = ep->create_time_ms * 10;
break;
case TM_MODIFY:
t = GET16_A(ep->modify_time);
d = GET16_A(ep->modify_date);
+ ms = ep->modify_time_ms * 10;
break;
case TM_ACCESS:
t = GET16_A(ep->access_time);
@@ -1188,21 +1198,33 @@ void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
tp->day = (d & 0x001F);
tp->mon = (d >> 5) & 0x000F;
tp->year = (d >> 9);
+
+ if (ms >= 1000) {
+ ms -= 1000;
+ tp->sec++;
+ }
}

void fat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
u8 mode)
{
+ u8 ms;
u16 t, d;
struct dos_dentry_t *ep = (struct dos_dentry_t *)p_entry;

t = (tp->hour << 11) | (tp->min << 5) | (tp->sec >> 1);
d = (tp->year << 9) | (tp->mon << 5) | tp->day;

+ ms = tp->millisec;
+ if (tp->sec & 1) {
+ ms += 1000;
+ }
+
switch (mode) {
case TM_CREATE:
SET16_A(ep->create_time, t);
SET16_A(ep->create_date, d);
+ ep->create_time_ms = ms / 10;
break;
case TM_MODIFY:
SET16_A(ep->modify_time, t);
@@ -1214,20 +1236,28 @@ void fat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
void exfat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
u8 mode)
{
+ u8 ms;
u16 t, d;
struct file_dentry_t *ep = (struct file_dentry_t *)p_entry;

t = (tp->hour << 11) | (tp->min << 5) | (tp->sec >> 1);
d = (tp->year << 9) | (tp->mon << 5) | tp->day;

+ ms = tp->millisec;
+ if (tp->sec & 1) {
+ ms += 1000;
+ }
+
switch (mode) {
case TM_CREATE:
SET16_A(ep->create_time, t);
SET16_A(ep->create_date, d);
+ ep->create_time_ms = ms / 10;
break;
case TM_MODIFY:
SET16_A(ep->modify_time, t);
SET16_A(ep->modify_date, d);
+ ep->modify_time_ms = ms / 10;
break;
case TM_ACCESS:
SET16_A(ep->access_time, t);
--
2.20.1