errcode_t io_close(io_channel *channel)
{
errcode_t ret = 0;
io_destroy_cache(channel);
if (close(channel->io_fd) < 0)
ret = errno;
ocfs2_free(&channel->io_name);
ocfs2_free(&channel);
return ret;
}
void o2fsck_init_cache(o2fsck_state *ost, enum o2fsck_cache_hint hint)
{
errcode_t ret;
uint64_t blocks_wanted, av_blocks;
int leave_room;
ocfs2_filesys *fs = ost->ost_fs;
int max_slots = OCFS2_RAW_SB(fs->fs_super)->s_max_slots;
uint64_t pages_wanted, avpages;
switch (hint) {
case O2FSCK_CACHE_MODE_FULL:
leave_room = 1;
blocks_wanted = fs->fs_blocks;
break;
case O2FSCK_CACHE_MODE_JOURNAL:
/*
* We need enough blocks for all the journal
* data. Let's guess at 256M journals.
*/
leave_room = 0;
blocks_wanted = (uint64_t)max_slots * 1024 * 1024 * 256;
blocks_wanted = ocfs2_bytes_to_blocks(fs,
blocks_wanted);
break;
case O2FSCK_CACHE_MODE_NONE:
return;
default:
assert(0);
}
verbosef("Want %"PRIu64" blocks for the I/O cache\n",
blocks_wanted);
/*
* leave_room means that we don't want our cache to be taking
* all available memory. So we try to get twice as much as we
* want; if that works, we know that getting exactly as much as
* we want is going to be safe.
*/
if (leave_room)
blocks_wanted <<= 1;
if (blocks_wanted > INT_MAX)
blocks_wanted = INT_MAX;
av_blocks = blocks_wanted;
avpages = sysconf(_SC_AVPHYS_PAGES);
pages_wanted = blocks_wanted * fs->fs_blocksize / getpagesize();
if (pages_wanted > avpages)
av_blocks = avpages * getpagesize() / fs->fs_blocksize;
while (blocks_wanted > 0) {
io_destroy_cache(fs->fs_io);
verbosef("Asking for %"PRIu64" blocks of I/O cache\n",
blocks_wanted);
if (blocks_wanted > av_blocks)
blocks_wanted = av_blocks;
ret = io_init_cache(fs->fs_io, blocks_wanted);
if (!ret) {
/*
* We want to pin our cache; there's no point in
* having a large cache if half of it is in swap.
* However, some callers may not be privileged
* enough, so once we get down to a small enough
* number (512 blocks), we'll stop caring.
*/
ret = io_mlock_cache(fs->fs_io);
if (ret && (blocks_wanted <= 512))
ret = 0;
}
if (!ret) {
verbosef("Got %"PRIu64" blocks\n", blocks_wanted);
/*
* We've found an allocation that works. If
* we're not leaving room, we're done. But if
* we're leaving room, we clear leave_room and go
* around again. We expect to succeed there.
*/
if (!leave_room) {
cache_blocks = blocks_wanted;
break;
}
verbosef("Leaving room for other %s\n", "allocations");
leave_room = 0;
}
blocks_wanted >>= 1;
}
}