IDE: Save a call to PageHighMem()

PageHighMem() isn't cheap so avoid calling it twice on the same page.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/ide/ide-taskfile.c

@@ -236,6 +236,7 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
 
 	while (len) {
 		unsigned nr_bytes = min(len, cursg->length - cmd->cursg_ofs);
+		int page_is_high;
 
 		if (nr_bytes > PAGE_SIZE)
 			nr_bytes = PAGE_SIZE;
@@ -247,7 +248,8 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
 		page = nth_page(page, (offset >> PAGE_SHIFT));
 		offset %= PAGE_SIZE;
 
-		if (PageHighMem(page))
+		page_is_high = PageHighMem(page);
+		if (page_is_high)
 			local_irq_save(flags);
 
 		buf = kmap_atomic(page, KM_BIO_SRC_IRQ) + offset;
@@ -268,7 +270,7 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
 
 		kunmap_atomic(buf, KM_BIO_SRC_IRQ);
 
-		if (PageHighMem(page))
+		if (page_is_high)
 			local_irq_restore(flags);
 
 		len -= nr_bytes;