vbatts/grub
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

bufio: Round up block size to power of 2

Browse source 
Rounding up the bufio->block_size to meet power of 2 to facilitate next_buf
calculation in grub_bufio_read().

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Michael Chang 2018-04-24 14:13:04 +08:00 committed by Vincent Batts
parent d86ee9b3e3
commit a09de36b3c
1 changed files with 7 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
grub-core/io/bufio.c
View file

@ -61,6 +61,13 @@ grub_bufio_open (grub_file_t io, int size)
size = ((io->size > GRUB_BUFIO_MAX_SIZE) ? GRUB_BUFIO_MAX_SIZE : size = ((io->size > GRUB_BUFIO_MAX_SIZE) ? GRUB_BUFIO_MAX_SIZE :
io->size); io->size);
/*
* Round up size to power of 2 which the binary math to
* calculate next_buf in grub_bufio_read() requires.
*/
while (size & (size - 1))
size = (size | (size - 1)) + 1;
bufio = grub_zalloc (sizeof (struct grub_bufio) + size); bufio = grub_zalloc (sizeof (struct grub_bufio) + size);
if (! bufio) if (! bufio)
{ {