This completes the fix from r185586.
PR: kern/139059
Reported by: Daniel Braniss <danny@cs.huji.ac.il>
Submitted by: Jaakko Heinonen <jh@saunalahti.fi>
Tested by: Daniel Braniss <danny@cs.huji.ac.il>
MFC after: 3 days
a large page size that is greater than malloc(3)'s default chunk size but
less than or equal to 4 MB, then increase the chunk size to match the large
page size.
Most often, using a chunk size that is less than the large page size is not
a problem. However, consider a long-running application that allocates and
frees significant amounts of memory. In particular, it frees enough memory
at times that some of that memory is munmap()ed. Up until the first
munmap(), a 1MB chunk size is just fine; it's not a problem for the virtual
memory system. Two adjacent 1MB chunks that are aligned on a 2MB boundary
will be promoted automatically to a superpage even though they were
allocated at different times. The trouble begins with the munmap(),
releasing a 1MB chunk will trigger the demotion of the containing superpage,
leaving behind a half-used 2MB reservation. Now comes the real problem.
Unfortunately, when the application needs to allocate more memory, and it
recycles the previously munmap()ed address range, the implementation of
mmap() won't be able to reuse the reservation. Basically, the coalescing
rules in the virtual memory system don't allow this new range to combine
with its neighbor. The effect being that superpage promotion will not
reoccur for this range of addresses until both 1MB chunks are freed at some
point in the future.
Reviewed by: jasone
MFC after: 3 weeks
It is quite inconvenient that if an application for xterm uses 256 color
mode, text suddenly starts to blink (because of ;5; in the middle).
We'd better just implement 256 color mode and add a conversion routine
from 256 to 8 color mode, which doesn't seem to be too bad in practice.
Remapping colors is done quite simple. If one of the channels is most
actively represented, primary colors are used. If two channels are most
actively represented, secondary colors are used. If all three channels
are equal (gray), it picks between black and white.
Reported by: Paul B. Mahol <onemda gmail com>
In some cases events may occur that move the cursor outside the
scrolling region while in origin mode, which is normally not possible.
Events like these include:
- Alignment test.
- Restore cursor.
Properly switch off origin mode in these cases.
MFC after: 1 month
devices that we also support, just not by default (thus only LINT or
module builds by default).
While currently there is only "/dev/full" [2], we are planning to see more
in the future. We may decide to change the module/dependency logic in the
future should the list grow too long.
This is not part of linux.ko as also non-linux binaries like kFreeBSD
userland or ports can make use of this as well.
Suggested by: rwatson [1] (name)
Submitted by: ed [2]
Discussed with: markm, ed, rwatson, kib (weeks ago)
Reviewed by: rwatson, brueffer (prev. version)
PR: kern/68961
MFC after: 6 weeks
unmount. In that case we cannot depend on the proper order of invalidating
vnodes, so we have to free resources when we have a chance.
PR: kern/139062
Reported by: trasz
MFC after: 3 days
well with forced unmounts when GFS vnodes are referenced.
- Make other preparations to GFS for forced unmounts.
PR: kern/139062
Reported by: trasz
MFC after: 3 days
- Clear all registers before calling real mode interrupt handlers as we did
for dpms and vesa and re-enable the function as it should be fixed by this.
- Tidy up register access. For example, when we call INT 0x15, AH=0xc0,
we used to initialize AX=0xc000 to clear AL at the same time but it is
very confusing. We don't have to do this any more because we are explicitly
clearing all registers now.
- Check size of system configuration table although it is almost always 8.
This is to make sure we are not reading some random low physical memory.
Hopefully it is just zero in that case. :-)
- Fix some style nits and add more comments.
Submitted by: paradox (ddkprog yahoo com)[1]
memory to support them. Some adapters have expansible memory slots but
video mode table is static. In this case, unusable modes may be reported.
Submitted by: paradox (ddkprog yahoo com) (initial patch)
- Remove CS and IP registers from x86bios.h. They have no use for us.
- Adjust register dump to make it little bit more useful for debugging.
Submitted by: paradox (ddkprog yahoo com)[1] (initial version)
Just run this to switch to xterm:
printf '\e[=T'
If you get bored and want to switch back to cons25, run this:
printf '\e[=1T'
I can now send an email to the lists, asking whether people are
interested in trying the xterm emulator.
I noticed a small inconsistency in delete and insert line between xterm
and libteken. libteken allows these actions to happen while the cursor
is placed outside the scrolling region, while xterm does not.
This behaviour seems to be VT100-like. Confirmation:
http://www.vt100.net/docs/vt102-ug/chapter5.html
"This sequence is ignored when cursor is outside scrolling region."
MFC after: 1 month
check if there are readers blocked by us via URWLOCK_WRITE_WAITERS flag,
and resume the readers. The error must be EAGAIN, otherwise there must
have memory problem, and nobody can rescue the buggy application.
The revision 197445 might be reverted.
This means we can finally do things like VT100 box drawing when using
Syscons (8-bit characters). As far as I know, the only remaining issue
is the absense of proper escape sequences for special keyboard
characters (cursor, F1 to F12, etc) and xterm emulation should be ready
for general use.
Enabling xterm would have the following advantages:
- Easier possible migration to Unicode. cons25 termcap entries are very
8-bit centric. They use things like CP437 characters for box drawing,
etc.
- Better support for SSH'ing to other operating systems/devices. Most
switches use VT100-style admin interfaces.
- Reduced bandwidth, because applications can now use things like
scrolling regions.
- You can finally use applications like dtach(1) on both the console and
inside an xterm.
Also align setup descriptor on 32 bytes boundary. Tx buffer have no
alignment limitation so create dmamap without alignment
restriction[1]. Rx buffer still seems to require 4 bytes alignment
limitation but we can simply use MCLBYTES for size to map the
buffer instead of TULIP_DATA_PER_DESC as the buffer is allocated
with m_getcl(9).
de(4) supports up to TULIP_MAX_TXSEG segments for Tx buffers,
increase maximum dma segment size to TULIP_MAX_TXSEG * MCLBYTES.
While I'm here remove TULIP_DATA_PER_DESC as it is not used anymore.
This should fix de(4) breakage introduced after r176206.
Submitted by: jhb [1]
Reported by: WATANABE Kazuhiro < CQG00620 <> nifty dot ne dot jp >
Tested by: WATANABE Kazuhiro < CQG00620 <> nifty dot ne dot jp >,
Takahashi Yoshihiro < nyan <> jp dot freebsd dot org >
driver load. This fixes crash on atapicam module load on systems,
where some ata channels (usually ata1) was probed, but failed to attach.
Reviewed by: jhb, imp
Tested by: many
following vnops will fail. This is very important, because without this change
vnode could be reclaimed at any point, even if we increased usecount. The only
way to ensure that vnode won't be reclaimed was to lock it, which would be very
hard to do in ZFS without changing a lot of code. With this change simply
increasing usecount is enough to be sure vnode won't be reclaimed from under
us. To be precise it can still be reclaimed but we won't be able to see it,
because every try to enter ZFS through VFS will result in EIO.
The only function that cannot return EIO, because it is needed for vflush() is
zfs_root(). Introduce ZFS_ENTER_NOERROR() macro that only locks
z_teardown_lock and never returns EIO.
MFC after: 3 days
o introduce PCIE_REGMAX and use it instead of ad-hoc constant
o where 'reg' parameter/variable is not already unsigned, cast it to
unsigned before comparison with maximum value to cut off negative
values
o use PCI_SLOTMAX in several places where 31 or 32 were explicitly used
o drop redundant check of 'bytes' in i386 pciereg_cfgread() - valid
values are already checked in the subsequent switch
Reviewed by: jhb
MFC after: 1 week
query umtx also if the shared waiters bit is set on a shared lock.
The writer starvation avoidance technique, infact, can lead to shared
waiters on a shared lock which can bring to a missed wakeup and thus
to a deadlock if the right bit is not checked (a notable case is the
writers counterpart to be handled through expired timeouts).
Fix that by checking for the shared waiters bit also when unlocking the
shared locks.
That bug was causing a reported MySQL deadlock.
Many thanks go to Nick Esborn and his employer DesertNet which provided
time and machines to identify and fix this issue.
PR: thread/135673
Reported by: Nick Esborn <nick at desert dot net>
Tested by: Nick Esborn <nick at desert dot net>
Reviewed by: jeff
save/clear/restore flags but emulated flags have no effect on the host.
I believe BIOS writers never meant to run their code in emulated
environment with interrupt enabled. :-)
- Use memcpy(3) instead of copying individual members. I believe struct
x86regs was intentionally copied from the first half of struct x86emu_regs
for this very purpose.
- Fix some style nits and consistencies.
Reviewed by: delphij, paradox (ddkprog yahoo com)
