UBI (Latin: "where?") manages multiple logical volumes on a single
flash device, specifically supporting NAND flash devices. UBI provides
a flexible partitioning concept which still allows for wear-levelling
across the whole flash device.
In a sense, UBI may be compared to the Logical Volume Manager
(LVM). Whereas LVM maps logical sector numbers to physical HDD sector
numbers, UBI maps logical eraseblocks to physical eraseblocks.
More information may be found at
http://www.linux-mtd.infradead.org/doc/ubi.html
Partitioning/Re-partitioning
An UBI volume occupies a certain number of erase blocks. This is
limited by a configured maximum volume size, which could also be
viewed as the partition size. Each individual UBI volume's size can
be changed independently of the other UBI volumes, provided that the
sum of all volume sizes doesn't exceed a certain limit.
UBI supports dynamic volumes and static volumes. Static volumes are
read-only and their contents are protected by CRC check sums.
Bad eraseblocks handling
UBI transparently handles bad eraseblocks. When a physical
eraseblock becomes bad, it is substituted by a good physical
eraseblock, and the user does not even notice this.
Scrubbing
On a NAND flash bit flips can occur on any write operation,
sometimes also on read. If bit flips persist on the device, at first
they can still be corrected by ECC, but once they accumulate,
correction will become impossible. Thus it is best to actively scrub
the affected eraseblock, by first copying it to a free eraseblock
and then erasing the original. The UBI layer performs this type of
scrubbing under the covers, transparently to the UBI volume users.
Erase Counts
UBI maintains an erase count header per eraseblock. This frees
higher-level layers (like file systems) from doing this and allows
for centralized erase count management instead. The erase counts are
used by the wear-levelling algorithm in the UBI layer. The algorithm
itself is exchangeable.
Booting from NAND
For booting directly from NAND flash the hardware must at least be
capable of fetching and executing a small portion of the NAND
flash. Some NAND flash controllers have this kind of support. They
usually limit the window to a few kilobytes in erase block 0. This
"initial program loader" (IPL) must then contain sufficient logic to
load and execute the next boot phase.
Due to bad eraseblocks, which may be randomly scattered over the
flash device, it is problematic to store the "secondary program
loader" (SPL) statically. Also, due to bit-flips it may become
corrupted over time. UBI allows to solve this problem gracefully by
storing the SPL in a small static UBI volume.
UBI volumes vs. static partitions
UBI volumes are still very similar to static MTD partitions:
* both consist of eraseblocks (logical eraseblocks in case of UBI
volumes, and physical eraseblocks in case of static partitions;
* both support three basic operations - read, write, erase.
But UBI volumes have the following advantages over traditional
static MTD partitions:
* there are no eraseblock wear-leveling constraints in case of UBI
volumes, so the user should not care about this;
* there are no bit-flips and bad eraseblocks in case of UBI volumes.
So, UBI volumes may be considered as flash devices with relaxed
restrictions.
Where can it be found?
Documentation, kernel code and applications can be found in the MTD
gits.
What are the applications for?
The applications help to create binary flash images for two purposes: pfi
files (partial flash images) for in-system update of UBI volumes, and plain
binary images, with or without OOB data in case of NAND, for a manufacturing
step. Furthermore some tools are/and will be created that allow flash content
analysis after a system has crashed..
Who did UBI?
The original ideas, where UBI is based on, were developed by Andreas
Arnez, Frank Haverkamp and Thomas Gleixner. Josh W. Boyer and some others
were involved too. The implementation of the kernel layer was done by Artem
B. Bityutskiy. The user-space applications and tools were written by Oliver
Lohmann with contributions from Frank Haverkamp, Andreas Arnez, and Artem.
Joern Engel contributed a patch which modifies JFFS2 so that it can be run on
a UBI volume. Thomas Gleixner did modifications to the NAND layer. Alexander
Schmidt made some testing work as well as core functionality improvements.
Signed-off-by: Artem B. Bityutskiy <dedekind@linutronix.de>
Signed-off-by: Frank Haverkamp <haver@vnet.ibm.com>
* master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
[PARPORT] SUNBPP: Fix OOPS when debugging is enabled.
[SPARC] openprom: Switch to ref counting PCI API
The packet driver is assuming (reasonably) that the (undocumented)
request.errors is an errno. But it is in fact some mysterious bitfield. When
things go wrong we return weird positive numbers to the VFS as pointers and it
goes oops.
Thanks to William Heimbigner for reporting and diagnosis.
(It doesn't oops, but this driver still doesn't work for William)
Cc: William Heimbigner <icxcnika@mar.tar.cc>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tweak a register setting to prevent the tx mailbox from halting.
Update version to 1.5.8.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sparc64:
drivers/net/hamradio/baycom_ser_fdx.c: In function `ser12_open':
drivers/net/hamradio/baycom_ser_fdx.c:417: error: `NR_IRQS' undeclared (first us
e in this function)
drivers/net/hamradio/baycom_ser_fdx.c:417: error: (Each undeclared identifier is
reported only once
drivers/net/hamradio/baycom_ser_fdx.c:417: error: for each function it appears i
n.)
Cc: Folkert van Heusden <folkert@vanheusden.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Broken by 4a1728a28a which switched the
return semantics of read_mii_word() but didn't fix usage of
read_mii_word() to conform to the new semantics.
Setting carrier to off based on the NO_CARRIER flag is also incorrect as
that flag only triggers on TX failure and therefore isn't correct when
no frames are being transmitted. Since there is already a 2*HZ MII
carrier check going on, defer to that.
Add a TRUST_LINK_STATUS feature flag for adapters where the LINK_STATUS
flag is actually correct, and use that rather than the NO_CARRIER flag.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The sis900 driver appears to have a bug in which the receive routine
passes the skbuff holding the received frame to the network stack before
refilling the buffer in the rx ring. If a new skbuff cannot be allocated, the
driver simply leaves a hole in the rx ring, which causes the driver to stop
receiving frames and become non-recoverable without an rmmod/insmod according to
reporters. This patch reverses that order, attempting to allocate a replacement
buffer first, and receiving the new frame only if one can be allocated. If no
skbuff can be allocated, the current skbuf in the rx ring is recycled, dropping
the current frame, but keeping the NIC operational.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The following patch fixes a kernel bug in depca_platform_probe().
We don't use a dynamic pointer for pldev->dev.platform_data, so it seems
that the correct way to proceed if platform_device_add(pldev) fails is
to explicitly set the pldev->dev.platform_data pointer to NULL, before
calling the platform_device_put(pldev), or it will be kfree'ed by
platform_device_release().
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Commit 40b36daa introduced possibility that serial8250_backup_timeout() ->
serial8250_handle_port() locks port.lock without disabling irqs, thus
allowing deadlock against interrupt handler (port.lock is acquired in
serial8250_interrupt()).
Spotted by lockdep.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Two functions are called from __devinit context, but they are marked as
__init. Fix this.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On ia64, kernel headers define REGION_OFFSET so we can't use that.
Reported by Andrew Morton.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: David Hubbard <david.c.hubbard@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
irq values are u32, not u8. Large irq numbers will be truncated,
free_irq may free a different irq.
Remove incorrectly sized struct member and use the one from pci_dev.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use relative time, not absolute. Discovered by Jung-Ik (John) Lee
<jilee@google.com>.
Cc: Jung-Ik (John) Lee <jilee@google.com>
Acked-by: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pcd_lock and pf_spin_lock are passed to blk_init_queue() which, seeing them
as valid lock pointer, sets it as ->queue_lock.
The problem is that pcd_lock and pf_spin_lock aren't initialized anywhere.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There was schedule() missing in the TIOCMIWAIT ioctl. Solve it by moving
the code to the wait_event_interruptible.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jan Yenya Kasprzak <kas@fi.muni.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There was schedule() missing in the TIOCMIWAIT ioctl. Solve it by moving
the code to the wait_event_interruptible.
Cc: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I encountered the following kernel panic. The cause of this problem was
NULL pointer access in check_modem_status() in 8250.c. I confirmed this
problem is fixed by the attached patch, but I don't know this is the
correct fix.
sadc[4378]: NaT consumption 2216203124768 [1]
Modules linked in: binfmt_misc dm_mirror dm_mod thermal processor fan
container button sg e100 eepro100 mii ehci_hcd ohci_hcd
Pid: 4378, CPU 0, comm: sadc
psr : 00001210085a2010 ifs : 8000000000000289 ip : [<a000000100482071>]
Not tainted
ip is at check_modem_status+0xf1/0x360
Call Trace:
[<a000000100013940>] show_stack+0x40/0xa0
[<a0000001000145a0>] show_regs+0x840/0x880
[<a0000001000368e0>] die+0x1c0/0x2c0
[<a000000100036a30>] die_if_kernel+0x50/0x80
[<a000000100037c40>] ia64_fault+0x11e0/0x1300
[<a00000010000bdc0>] ia64_leave_kernel+0x0/0x280
[<a000000100482070>] check_modem_status+0xf0/0x360
[<a000000100482300>] serial8250_get_mctrl+0x20/0xa0
[<a000000100478170>] uart_read_proc+0x250/0x860
[<a0000001001c16d0>] proc_file_read+0x1d0/0x4c0
[<a0000001001394b0>] vfs_read+0x1b0/0x300
[<a000000100139cd0>] sys_read+0x70/0xe0
[<a00000010000bc20>] ia64_ret_from_syscall+0x0/0x20
[<a000000000010620>] __kernel_syscall_via_break+0x0/0x20
Fix the possible NULL pointer access in check_modem_status() in 8250.c. The
check_modem_status() would access 'info' member of uart_port structure, but it
is not initialized before uart_open() is called. The check_modem_status() can
be called through /proc/tty/driver/serial before uart_open() is called.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi2005@soft.fujitsu.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The debugging code would dereference __iomem pointers instead
of going through sbus_{read,write}{b,w,l}().
Signed-off-by: David S. Miller <davem@davemloft.net>
USRobotics Wireless Adapter (Model 5423) works well with current
zd1211rw driver also (i have tested 2.6.18, 2.6.20 and 2.6.21-rc7).
It just needs its ID added to the list of devices.
Signed-off-by: S.Çağlar Onur <caglar@pardus.org.tr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The MAC address assignment at module loading is simply forgotten.
The bug at module unloading is caused by an incorrect call.
The bug at module unloading does not only happen for sunqe,
sunlance and sunhme (sbus) suffer from it too.
I've tested this on my SS20.
Signed-off-by: Marcel van Nies <morcles@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replacing kmalloc/memset combination with kzalloc.
Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ide_hwif_to_major[] has only 10 entries as there are 10 major numbers
reserved for IDE (if somebody needs more it shouldn't be hard to fix).
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
The driver crashes the kernel on HPT302N chips due to the missing initializer
for 'hpt302n.settings' having been unfortunately overlooked so far. :-<
Much thanks to Mike Mattie for pin-pointing the reason of crash.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add PCI ID for a newer variant of cardbus CF/IDE adapter card.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This reverts commit 60cba200f1. It's been
linked to lockups of the e1000 hardware, see for example
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=229603
but it's likely that the commit itself is not really introducing the
bug, but just allowing an unrelated problem to rear its ugly head (ie
one current working theory is that the code exposes us to a hardware
race condition by decreasing the amount of time we spend in each NAPI
poll cycle).
We'll revert it until root cause is known. Intel has a repeatable
reproduction on two different machines and bus traces of the hardware
doing something bad.
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg KH <gregkh@suse.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Auke Kok <auke-jan.h.kok@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A small number of SiS setups require special handling (not many judging
by how long this dumb bug survived). A couple of Fedora 7 devel testers
hit an Oops on pata_sis loading which is caused by terminal confusion
between chipset as 'the chipset we have found' and chipset as 'array
iterator'
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
From: Paul Mackerras <paulus@samba.org>
This fixes:
Subject: kernel BUG at net/core/skbuff.c in linux-2.6.21-rc6
process_input_packet() treats the case where the first byte is 0xff
(PPP_ALLSTATIONS) but the second byte is 0x03 (PPP_UI) as indicating a
packet with a PPP protocol number of 0xff. Arguably that's wrong
since PPP protocol 0xff is reserved, and the RFC does envision the
possibility of receiving frames where the control field has values
other than 0x03.
Signed-off-by: David S. Miller <davem@davemloft.net>
The Yukon FE (100mbit only) chips do not support large packets.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The Yukon EC Ultra chips have transmit settings for store and
forward and PCI buffering. By setting these appropriately, normal
performance goes from 750Mbytes/sec to 940Mbytes/sec (non-jumbo).
It is also possible to do Jumbo mode, but it means turning off
TSO and checksum offload so the performance gets worse. There isn't
enough buffering for checksum offload to work.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Need to make sure and disable ASF on all chip types. Otherwise, there may be
random reboots.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
There should never be descriptor error unless hardware or driver is buggy.
But if an error occurs, print useful information, clear irq, and recover.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This device is having all sorts of problems that lead to data corruption
and system instability. It gets receive status and data out of order,
it generates descriptor and TSO errors, etc.
Until the problems are resolved, it should not be used by anyone
who cares about there system.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The basic structure of "normal" UDP/IP/Ethernet
frames (that actually work):
- It starts with the Ethernet header (dest MAC, src MAC, etc.)
- The next part is occupied by the IP header (version info, length of
packet, id=0, fragment offset=0, checksum, from / to address, etc.)
- Then comes the UDP header (src / dest port, length, checksum)
- Actual payload
- Ethernet checksum
Now what's different for IP fragment:
- The IP header has id set to some value (same for all fragments),
offset is set appropriately (i.e. 0 for first fragment, following
according to size of other fragments), size is the length of the frame.
- UDP header is unchanged. I.e. length is according to full UDP
datagram, not just the part within the actual frame! But this is only
true within the first frame: all following frames don't have a valid
UDP-header at all.
The spidernet silicon seems to be quite intelligent: It's able to
compute (IP / UDP / Ethernet) checksums on the fly and tests if frames
are conforming to RFC -- at least conforming to RFC on complete frames.
But IP fragments are different as explained above:
I.e. for IP fragments containing part of a UDP datagram it sees
incompatible length in the headers for IP and UDP in the first frame
and, thus, skips this frame. But the content *is* correct for IP
fragments. For all following frames it finds (most probably) no valid
UDP header at all. But this *is* also correct for IP fragments.
The Linux IP-stack seems to be clever in this point. It expects the
spidernet to calculate the checksum (since the module claims to be able
to do so) and marks the skb's for "normal" frames accordingly
(ip_summed set to CHECKSUM_HW).
But for the IP fragments it does not expect the driver to be capable to
handle the frames appropriately. Thus all checksums are allready
computed. This is also flaged within the skb (ip_summed set to
CHECKSUM_NONE).
Unfortunately the spidernet driver ignores that hints. It tries to send
the IP fragments of UDP datagrams as normal UDP/IP frames. Since they
have different structure the silicon detects them the be not
"well-formed" and skips them.
The following one-liner against 2.6.21-rc2 changes this behavior. If the
IP-stack claims to have done the checksumming, the driver should not
try to checksum (and analyze) the frame but send it as is.
Signed-off-by: Norbert Eicker <n.eicker@fz-juelich.de>
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Remove assumption that PHY interrupts use GPIOs 3 and 5.
Deal with PHY interrupts connected to any GPIO pins.
Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Reuse the incoming skb when a clientless abort req is recieved.
The release of RDMA connections HW resources might be deferred in
low memory situations.
Ensure that no further activity is passed up to the RDMA driver
for these connections.
Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Nonpae guest pdes are shadowed by two pae ptes, so we double the offset
twice: once to account for the pte size difference, and once because we
need to shadow pdes for a single guest pde.
But when writing to the upper guest pde we also need to truncate the
lower bits, otherwise the multiply shifts these bits into the pde index
and causes an access to the wrong shadow pde. If we're at the end of the
page (accessing the very last guest pde) we can even overflow into the
next host page and oops.
Signed-off-by: Avi Kivity <avi@qumranet.com>
