Change a rounding operation that had missing braces into a roundup2()

macro.  Adjust the buffer clipping code to work as expected.

This prevented a number of machines in the FreeBSD.org cluster from
booting due to "ZFS: i/o error - all block copies unavailable"
after an unclean shutdown.
This commit is contained in:
Peter Wemm 2016-05-03 00:09:13 +00:00
parent d546e47aa0
commit d8818fce69

View File

@ -224,21 +224,18 @@ vdev_read(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
while (bytes > 0) {
nb = bytes / DEV_BSIZE;
if (nb > READ_BUF_SIZE / DEV_BSIZE)
nb = READ_BUF_SIZE / DEV_BSIZE;
/*
* Ensure that the read size plus the leading offset does not
* exceed the size of the read buffer.
*/
if (nb * DEV_BSIZE + diff > READ_BUF_SIZE)
nb -= diff / DEV_BSIZE;
if (nb > (READ_BUF_SIZE - diff) / DEV_BSIZE)
nb = (READ_BUF_SIZE - diff) / DEV_BSIZE;
/*
* Round the number of blocks to read up to the nearest multiple
* of DEV_GELIBOOT_BSIZE.
*/
alignnb = nb + (diff / DEV_BSIZE) +
(DEV_GELIBOOT_BSIZE / DEV_BSIZE - 1) & ~
(unsigned int)(DEV_GELIBOOT_BSIZE / DEV_BSIZE - 1);
alignnb = roundup2(nb * DEV_BSIZE + diff, DEV_GELIBOOT_BSIZE)
/ DEV_BSIZE;
if (drvread(dsk, dmadat->rdbuf, alignlba, alignnb))
return -1;