Make the public interface more systematically named.
Remove the alternate method, it doesn't do any good, only ruins performance.
Add counters to profile the usage of the 8 access functions.
Apply the beer-ware to my code.
The weird +/- counts are caused by two repocopies behind the scenes:
kern/kern_clock.c -> kern/kern_tc.c
sys/time.h -> sys/timetc.h
(thanks peter!)
substitute BUF_WRITE(foo) for VOP_BWRITE(foo->b_vp, foo)
substitute BUF_STRATEGY(foo) for VOP_STRATEGY(foo->b_vp, foo)
This patch is machine generated except for the ccd.c and buf.h parts.
field in struct buf: b_iocmd. The b_iocmd is enforced to have
exactly one bit set.
B_WRITE was bogusly defined as zero giving rise to obvious coding
mistakes.
Also eliminate the redundant struct buf flag B_CALL, it can just
as efficiently be done by comparing b_iodone to NULL.
Should you get a panic or drop into the debugger, complaining about
"b_iocmd", don't continue. It is likely to write on your disk
where it should have been reading.
This change is a step in the direction towards a stackable BIO capability.
A lot of this patch were machine generated (Thanks to style(9) compliance!)
Vinum users: Greg has not had time to test this yet, be careful.
too many, so I removed the checks for the valid OUIs. We already do a
checksum of the entire ethernet address, so extra checking against the
OUI shouldn't be needed.
it into a ``shared'' .ko file. This intermediate file can be directly
linked into a static kernel. This isn't all that useful yet but will
become much more interesting shortly.
from iso88025.h.
o Add minimal llc support to iso88025_input.
o Clean up most of the source routing code.
* Submitted by: Nikolai Saoukh <nms@otdel-1.org>
4/16/100 -> 100/16/4 so that it matches all of the others.
o Since we went to all the trouble of getting the correct
working memory size actually use it.
* Submitted by: Nikolai Saoukh <nms@otdel-1.org>
it's options COMPAT_OLDISA and COMPAT_OLDPCI. This is meant to be a
fairly strong incentive to update the older drivers to newbus, but doesn't
(quite) leave anybody hanging with no hardware support. I was talking with
a few folks and I was encouraged to simply break or disable the shims but
that was a bit too drastic for my liking.
The new boot1/boot2 can load a.out and elf kernels directly.
I think the sys/pc98 version can go too as the sys/boot/pc98 code
appears to be functional, but I'll leave that for the pc98 folks.
"There can be only one."
prevent a page fault if the card is ejected while BPF is in use. This
could happen if DHCP or tcpdump was in use on that interface during
ejection. Other drivers may also require this modification.
Reviewed by: wes
possible for a panic to occur if BPF is in use on the interface at the
time of the call to if_detach. This happens because BPF maintains pointers
to the struct ifnet describing the interface, which is freed by if_detach.
To correct this problem, a new call, bpfdetach, is introduced. bpfdetach
locates BPF descriptor references to the interface, and NULLs them. Other
BPF code is modified so that discovery of a NULL interface results in
ENXIO (already implemented for some calls). Processes blocked on a BPF
call will also be woken up so that they can receive ENXIO.
Interface drivers that invoke bpfattach and if_detach must be modified to
also call bpfattach(ifp) before calling if_detach(ifp). This is relevant
for buses that support hot removal, such as pccard and usb. Patches to
all effected devices will not be committed, only to if_wi.c, due to
testing limitations. To reproduce the crash, load up tcpdump on you
favorite pccard ethernet card, and then eject the card. As some pccard
drivers do not invoke if_detach(ifp), this bug will not manifest itself
for those drivers.
Reviewed by: wes
new-bus Olicom driver, previously known as "ol". The new
driver unfortunately does not support ISA cards yet.
o Update the microcode files, interface library and include files
to the latest PowerMACH works version. Force even byte alignment
of adapter microcode.
o Roll in some of the patches from Nikolai Saoukh <nms@ethereal.ru>.
negotiation features (DT, ULTRA2, ULTRA, FAST). The offsets
where not properly updated when the DT entry was added and so
the driver could attempt to negotiate a speed faster than that
supported by the target device or even requested by the user
via SCSI-Select settings. *
o Update the target mode incoming command queue kernel index value
ever 128 commands instead of 32. This means that the kernel will
always try to keep its index (as seen on the card - the kernel may
actually have cleared more space) 128 commands ahead of where the
sequencer is adding entries.
o Use the HS_MAILBOX register instead of the KERNEL_TQINPOS location
in SRAM to indicate the kernel's target queue possition on Ultra2
cards. This avoids the "pause bug" on these cards and also turns
out to be much more efficient.
o When enabling or disabling a particular target id for target mode,
make sure that the taret id in the SCSIID register does not
reference an ID that is not to receive target selections. This
is only an issue on chips that support the multiple target id
feature where the value in SCSIID will still affect selection
behavior regardless of the values in the target id bit field
registers.
o Remove some target mode debugging printfs.
o Make sure that the sense length reported in ATIO commands is
always zero. This driver does not, yet, report HBA generated
sense information for accepted commands.
o Honor the CAM_TIME_INFINITY and CAM_TIME_DEFAULT values for
the CCB timeout field.
o Make the driver compile with AHC_DEBUG again.
* Noticed by: Andrew Gallatin<gallatin@cs.duke.edu>
an HBA. Garbage in this field confuses the driver in targdone().
o When completing a CCB on behalf of a user process, we need to
*de-queue* the ccb from our pending ccb list, not queue it again.
o All continue target I/O operations need to have a timeout set.
We use 5 seconds throughout this driver.
o Remove some logging printfs.
o During abort processing, remove ccbs that are on the pending queue
from the pending queue, not the work queue.
-current. It doesn't work yet as stable as the 3.x/PAO version of the
driver does, however, i get occasional `FDC direction bit not set' and
other weird messages, but it basically works at least.
The old (defunct) #ifdef FDC_YE stuff has been eliminated completely
now, PCMCIA-FDC specific functions have been implemented differently
where needed.
Unfortunately, due to the fact that the traditional PeeCee FDC with
its funny non-contiguous register space (one register for WD1003
harddisk controllers is interleaved into the FDC register set), and
Peter's subsequent changes involving two different bus space handles
for normal FDCs, the changes required for the Y-E stuff are more
complex than i'd love them to be. I've done my best to keep the logic
for normal FDCs intact.
Since the Y-E FDC seems to lose interrupts after a FDC reset
sometimes, i've also replaced the timeout logic in fd_turnoff() to
generate an artificial pseudo interrupt in case of a timeout while the
drive has still outstanding transfers waiting. This avoids the total
starvation of the driver that could be observed with highly damaged
media under 3.x/PAO. This part of the patch has been revied by bde
previously.
I've fixed a number of occasions where previous commits have been
missing the encapuslation of ISA DMA related functions inside
FDC_NODMA checks.
I've added one call to SET_BCDR() during preparation of the format
floppy operation. Floppy formatting has been totally broken before in
3.x/PAO (garbage ID fields have been written to the medium, causing
`wrong cylinder' errors upon media reading). This is just black
magic, i don't have the slightes idea _why_ this needs to be but just
copied over the hack that has been used by the PAO folks in the normal
read/write case anyway.
The entired device_busy() stuff seems to be pointless to me. In any
case, i had to add device_unbusy() calls symmetrical to the
device_busy() calls, otherwise the PCMCIA floppy driver could never be
deactivated. (As it used to be, it caused a `mark the device busier
and busier' situation.) IMHO, all block device drivers should be
marked busy based on active buffers still waiting for the driver, so
the device_unbusy() calls should probably go to biodone(). Only one
other driver (whose name escapes me at the moment) uses device_busy()
calls at all, so i question the value of all this...
I think this entire `device busy' logic simply doesn't fit for PCMCIA
&al. It cannot be the decision of some piece of kernel software to
declare a device `busy by now, you can't remove it', when the actual
physical power of removing it is the user pulling the card. The
kernel simply has to cope with the removal, however busy the device
might have been by the time of the removal, period. Perhaps a force
flag needs to be added?
Upon inserting the card a second time, i get:
WARNING: "fd" is usurping "fd"'s cdevsw[]
WARNING: "fd" is usurping "fd"'s bmaj
I suspect this is related to the XXX comment at the call to
cdevsw_add(). Does anybody know what the correct way is to cleanup
this?
- Microsoft IntelliMouse Explorer: 2 buttons on top, 2 side buttons
and a wheel which also acts as the middle button. The mouse is
recognized as "IntelliMouse Explorer".
- Genius NetScroll Optical: 2 buttons on top, 2 side buttons and a
wheel which also acts as the middle button. The mouse is recognized
as "NetMouse/NetScroll Optical".
- MouseSystems SmartScroll Mouse (OEM from Genius?): 3 buttons on top,
1 side button and a wheel. The mouse is recognized as Genius
"NetScroll".
- IBM ScrollPoint: 2 buttons on top and a stick between the buttons.
The stick can perform "horizontal scroll" in W*ndows environment.
The horizontal movement of the stick is detected. It is currently
mapped to the Z axis movement in the same way as the first wheel.
The mouse is recognized as "MouseMan+", as it is considered to be
a variation of MouseMan.
- A4 Tech 4D and 4D+ mice. These mice have two wheels! The movement
of the second wheel is reported as the Z axis movement in the
same way as the first wheel. These mice are recognized as "4D
Mouse" and "4D+ Mouse".
- Tweak IntelliMouse support code a bit so that less-than-compatible
wheel mice can work properly with the psm driver.
- Add driver configuration flags which correspond to the kernel
options PSM_HOOKRESUME and PSM_RESETAFTERSUSPEND, so that we don't
need to recompile the kernel when we need these functions.
- Properly keep track of the irq resource.
- Add a watchdog timer in case interrupts are lost (experimental).
- Add `detach' function (experimental).
- Properly keep track of resources (I/O ports and irq).
- Use bus_space_read/write() to access the ports.
- Add PnP IDs.
- Add a watchdog timer in case interrupts are lost (experimental).
- Add `detach' function (experimental).
from DWLPX to PCI space. Just a methods holder such that we have a parent
which is a "pcib" and we create a child which is a "pci". Add the appropriate
ivar code (which is for a hose #).
based upon presence/absence of ISA (there is no ISA bus on an 8200- okay,
well, there *could* be one in a DWLPX tray, but we don't support it)).
Most importantly change the interrupt resource map to cover a whole 16
bits. The 8200 uses 16 bit interrupt vectors which we construct that
contain the I/O-board, hose, an pci slot in them, and then we write these
vectors into the appropriate DWLPX registers. At any rate, a flat array
of 64 'IRQs' isn't enough.
to begin with. Redo newbus attachment code so that all the DMA mapping
and further pci attachment is done right. Insert config space functions
(jeez- how do you do type 1 cycles?). Do the interrupt setups, etc.
Basically, this is the core I/O module for 8200s, even though logically
it's the 3rd level down from the nominal principle backplane bus
(turbolaser). Still to be done here: S/G code isn't done yet, so we
better live with 2GB or less primary memory.
code (merge in progress made in NetBSD since the initial import to
FreeBSD). Create dwlpx as the child device. Of course, if we had
more h/w and time, we could find out whether the child device was
a FutureBus module, etc...Anyone ever actually seen one?
clean MI/MD driver, but it *does* actually work at this time. Updated
to use new make_dev stuff. A CONS_DRIVER declaration is also put in
so that this can be the real console for the 8200s.
not the current BPF device should report locally generated packets or not.
This allows sniffing applications to see only packets that are not generated
locally, which can be useful for debugging bridging problems, or other
situations where MAC addresses are not sufficient to identify locally
sourced packets. Default to true for this flag, so as to provide existing
behavior by default.
Introduce two new ioctls, BIOCGSEESENT and BIOCSSEESENT, which may be used
to manipulate this flag from userland, given appropriate privilege.
Modify bpf.4 to document these two new ioctl arguments.
Reviewed by: asmodai
this version include:
- Support for version 2.x firmware (2.42 or later recommended). This
means we are the only open-source driver supporting these adapters.
This code has only been tested on a Digital KZPCA adapter in an Alpha
system, but is believed to be correct. NOTE: EISA adapters are not
yet supported.
- Support the BIOS/Firmware initialisation handshake protocol. This
allows the driver to bring the card up to operational state even if
the BIOS can't be run (eg. if it's an x86 BIOS in an Alpha system).
- A working command pasthrough interface. This allows a user-space
configuration tool (under development) to issue arbitrary commands
to the controller or to devices in the system.
return ENXIO (Device not configured). Without this, vn_isdisk()
could (and did in the case of lstat() under fdesc) pass a NULL pointer
to devsw(), which caused a page fault.
Reviewed by: alfred
This avoids the unit number from going up indefinitely when
diconnecting and connecting 2 devices alternately.
Noticed by: nsayer (quite a while ago)
And stop calling DEVICE_NOMATCH at probe repeatedly. This stops the
message on the PCI VGA board from being printed when loading a PCI driver.
platform we're running on so we know how many bits to reserve at the top
end for the 'hose' value. It turns out that there's *just* enough room
to support all possible hoses on TurboLaser.
Reviewed by: gallatin@freebsd.org, dfr@free3bsd.org
This makes it possible to handle the done queue even when the end of tail
TD has ended up on the done queue as well (the xfer in this case is NULL
but the next field is valid, so we simply skip that element.
Make sure we mark all the handled transfers as handled.
Stop using powerhooks. They are a NetBSD-ism.
the unwary if the code were called in slightly different ways.
1) In ufs_bmaparray() the code for calculating 'runb' will stop one block
short of the first entry in an indirect block. i.e. if an indirect block
contains N block numbers b[0]..b[N-1] then the code will never check if
b[0] and b[1] are sequential. For reference, compare with the equivalent
code that deals with direct blocks.
2) In ufs_lookup() there is an off-by-one error in the test that checks
if dp->i_diroff is outside the range of the the current directory size.
This is completely harmless, since the following while-loop condition
'dp->i_offset < endsearch' is never met, so the code immediately
does a second pass starting at dp->i_offset = 0.
3) Again in ufs_lookup(), the condition in a sanity check is wrong
for directories that are longer than one block. This bug means that
the sanity check is only effective for small directories.
Submitted by: Ian Dowse <iedowse@maths.tcd.ie>
necessary. Pass an absolute block number too, instead of receiving a
relative one in realstrategy(), as bcache_strategy() requires this.
The fix is sligthly different from the one in the PR.
PR: 17098
Submitted by: John Hood <jhood@sitaranetworks.com>
was the last unit number received. If it changes, it flushes the cache.
Add bcache_flash().
The actual fix is sligthly different from the one in the PR.
PR: 17098
Submitted by: John Hood <jhood@sitaranetworks.com>
flushed if the unit changes. Compute the absolute offset before
bcache_strategy() instead of after.
The actual fix is sligthly different for the one in the PR.
PR: 17098
Submitted by: John Hood <jhood@sitaranetworks.com>
to recycle full fsids after only 16 mount/unmount's. This is probably
too often for exported fsids. Now we recycle the full fsids only
after 2^16 mount/ umount's and only ensure uniqueness in the lower 16
bits if there have been <= 256 calls to vfs_getnewfsid() since the
system started.
Previously, it was being called whether it was needed or not and the
ASU flag was being set (as a side affect of calling 'suser()') in
cases where superuser privileges were not actually needed. This was
all pointed out to me by Bruce Evans.
Reviewed by: bde
- Make iface nodes removable on shutdown since FreeBSD now supports
removable interfaces
- Simplify supporting new protocols using family_enqueue(); add a
few new ones including IPv6
- Add support for configurable interface mode using new
NGM_IFACE_POINT2POINT and NGM_IFACE_BROADCAST control messages
- Remove NGM_IFACE_GET_IFADDRS control message; it just duplicates
the functionality of SIOCGIFCONF
pte's from zero. The TLB is supposed to be invalidated when pte's are
changed _to_ zero, but this doesn't occur in all cases for global pages
(PG_G stops invltlb() from working, and invltlb_1pg() is not used
enough).
PR: 14141, 16568
Submitted by: dillon
rest of the code in (so changing media actually works.)
Add a few more register definitions for use with this and other new code.
Print a few details in the probe message; this should be useful in
bug reports and such but should not add to the clutter.
* i needed it anyway
* remove startccs and startcmd - done
* as those were used for the NetBSD start timeout
* multicast - done but UNTESTED
* I don't have the ability/facilty to test this
* rxlevel - done
* stats reported via raycontrol
* getparams ioctl - done
* reported via raycontrol
* start_join_done needs a restart in download_done - done
* now use netbsd style start up
removed spare timerh
implemented start_assoc in ray_ccs_done
bit more knfing
number was packed very wastefully, giving perfect non-uniqeness in
the lower 16 bits of fsids for filesystems with the same vfs type.
This made linux_stat() return perfectly non-unique (broken) 16-bit
st_dev's for nfs mount points, and effectively reduced mntid_base to
8 bits so that the vfs_getnewfsid() looped endlessly when there are
already 256 mounted filesystems with the required vfs type.
Approved by: jkh
print an error message which say, "include netinet/ip6.h".
This is postponed to apply to avoid tcpdump compile error.
Now apply this because tcpdump has been already fixed.
Approved by: jkh
Obtained from: KAME project
we get the com address. If so, we go ahead and return. Bruce thinks
there's a bug in the pccard layer that it terminates devices with
extreme prejustice rather than letting them deside for themselves when
to terminate (and he's likely right). This fix doesn't change that,
but instead works around it by checking for NULL pointers at more
places than before.
The detach routine still calls functions at interrupt level that
aren't reentrant. In theory this could cause a problem, but none
showed up in practice. Future versions should correct this problem,
likely by making the detach process a thread/process at the pccard
level. NEWCARD will do this, and the current pccard layer should
likely be modified to that as well, should it live long enough.
A few style nits of the same form that were in my original patch sent
off to bde were also fixed as part of this process. Mostly use of
!ptr and return ENOPARENS.
This should prevent a crash on suspend with an active ppp link as
well, but that wasn't tested.
Reviewed by: bde
Approved by: jkh
icmp6 error statistics based on sending interface.
This also prevent kernel panic when rcvif is not initialized after M_PKTHDR().
(The initialization issue also need to be fixed in the future.)
Approved by: jkh
Submitted by: k-sugyou@kame.net
requires current and desired network parameters, so I have created a network parameter structure and used two on them in the softc. This gives a bit of room of expansion. Re-wrote the update check in _net to work with this.
Tidyed up softc due to above.
Removed startccs and startcmd as they were only used by NetBSDs startup timeout.
Now most big problem of IPv6 is getting IPv6 address
assignment.
6to4 solve the problem. 6to4 addr is defined like below,
2002: 4byte v4 addr : 2byte SLA ID : 8byte interface ID
The most important point of the address format is that an IPv4 addr
is embeded in it. So any user who has IPv4 addr can get IPv6 address
block with 2byte subnet space. Also, the IPv4 addr is used for
semi-automatic IPv6 over IPv4 tunneling.
With 6to4, getting IPv6 addr become dramatically easy.
The attached patch enable 6to4 extension, and confirmed to work,
between "Richard Seaman, Jr." <dick@tar.com> and me.
Approved by: jkh
Reviewed by: itojun
keyboard port and interrupt is enabled and the driver is attached even
when the keyboard itself is not present when the system is booting.
(This has been the behavior through out 2.X and 3.X, but is somehow
broken in 4.0.)
# I certainly don't recommend people to `hot-plug' the AT keyboard,
# because the interface isn't designed for hot-plugging and such act
# will often break the keyboard controller. But, so many people want to
# do that anyway...
Approved by: jkh
ARP packets. This can incorrectly reject complete frames since the frame
could be stored in more than one mbuf.
The following patches fix the length comparisson, and add several
diagnostic log messages to the interrupt handler for out-of-the-norm ARP
packets. This should make ARP problems easier to detect, diagnose and
fix.
Submitted by: C. Stephen Gunn <csg@waterspout.com>
Approved by: jkh
Reviewed by: rwatson
VM_PROT_EXECUTE must be added to prot before calling vm_map_find.
Without this change, an mprotect on a shmat'ed region fails (when
it shouldn't). This bug was reported Feb 28 by Brooks Davis
<brooks@one-eyed-alien.net> on -hackers.
Reviewed by: bde
Approved by: jkh
o break out some of the probe routine the allocation of resources
into an attach routine
o Recognize PnP ids
o Allocate IRQ per card rather than per system
o Better polling reporting
o Remove unneeded include files in slot.h
o store a pseudo unit number on each device we find.
o Pass a unit number to interrupt/timeout routine and use it for polling
the hardware.
Tested on: My VAIO and with the Linksys pccard reader.
Approved by: jkh
particular ISDN card with the 2nd IDE controller and/or other cards
depending on configuration.
The amount of i/o ports allocated are reduced from 0x40 per range to
0x20 per range.
Submitted by: Andrew Gordon <arg@arg1.demon.co.uk>
Approved by: jkh
being accessed after the bp had been releaed. A simple move of the
brelse() solves the problem.
Approved by: jkh
Submitted by: Ian Dowse <iedowse@maths.tcd.ie>
Without this, kernel will panic at getsockopt() of IPSEC_POLICY.
Also make compilable libipsec/test-policy.c which tries getsockopt() of
IPSEC_POLICY.
Approved by: jkh
Submitted by: sakane@kame.net
according to draft-ietf-ipngwg-icmp-name-lookups-04 to 05 change.
This is necessary before 4.0, because,
-This change is non backword compatible
-Other KAME derived platforms applied 05
-Author of the draft said he never do backword imcompatible changes
again.
Approved by: jkh
Obtained from: KAME project
not actually used yet. This created a lot of prototypes.
I moved code around so that the functions are in the same order as NetBSD - this helps diff a lot.
Things that are missing are the TX routine and ifmedia stuff and ioctls
Not all of the stuff is enabled - we are missing calls in ccs_done and ioctl.
Promiscious mode is working.
Am almost ready to use the NetBSD start up routine - essentially all I need
to do is not use a seperate timer to call download_timo.
Other misc. things:
callout_stop is a newish feature for cancelling a timer without
argument checking it.
tried to add a sysctl knob but it doesn't work in the module
enabled infrastructure code to call netbsd bits.
Change disk names to `idad' to avoid naming conflicts with the controller,
and enable the new disk code to pick up the drives.
Tested by: david.w.james@bt.com (existing compaq support)
Reviewed by: msmith
Approved by: jordan
channel DMA. The problem was that the SDC bit (0x04) can only be set in
the MCE state.
PR: kern/16587
Submitted by: Matthew Reimer <mreimer@vpop.net>
Approved by: jkh (in person)
card configuration hassles.
Added a TODO list so I don't forget to finish stuff.
Tidyed up a lot of XXX.
Tidy'd and documented debugging - all DPRINTF have a debug level associated.
RAY_DEBUG = 1, will log packet errors.
#if protect common memory hacking
Don't rely on pccardd for common memory settings.
Added a simple transmit mode - reasonable performance but not great. Will do a version of the NetBSD chained buffers soon. Yup we have two way transmisson!
Fix a stupid bug in the common memory code - the ioctl call was
hidden behind a debug test!
with the known bogus currtpriority. This undoes the previous changes to
sys/i386/i386/trap.c, sys/alpha/alpha/trap.c, sys/sys/systm.h
Now we have the patch set approved by bde.
Approved by: bde
from panicing when disconnecting a USB Wacom Graphire tablet.
jhk approved the fix some time ago, but I forgot to actually commit the
thing.
Reported by: Dirk van Gulik <dirkx@webweaving.org>
Approved by: jhk
is responsible for this and this will lead to malloc 'freeing already
free' type panics. One was in the probe code, the other was in the
pccard eject? code.
Not explicitly approved by: jkh (but the first is fallout from subr_bus.c
rev 1.54 which was an approved commit, the second is the same problem)
adw_pci.c:
Update comments describing supported chips/cards.
adwcam.c:
adwlib.c:
adwlib.h:
Handle more error return codes from the firmware.
Break out the bus reset code into its own function.
Usa a constant for the bus reset hold delay.
Fix an interrupt race problem in adw_idle_cmd_send by
incorporating the poll loop for command completion.
Approved by: jkh@FreeBSDorg
to us, subr_bus.c will free it. This bug (panic: freeing already free)
was exposed by kern/subr_bus.c rev 1.54
Not explicitly approved by: jkh (but this is a showstopper and fallout of
the above approved change)
transferred, do it in complete_rqe instead.
launch_requests: Replace the inadvertently removed splbio() around the
main loop. It may not be necessary, but the biggest
test of this stuff are IDE disks, which I'm not
using.
Remove throttling code, I'm pretty sure it's not
needed any more.
Don't set B_ORDERED, it's not necessary either.
Objected-to-by: alfred
build_rq_buffer: Don't lose the B_ORDERED bit, it still has some
residual meaning. To do this right, Vinum needs to
look at the B_ORDERED bit and order the transfer
across all disks involved. That's an exercise for
another day.
Objected-to-by: alfred
Implicitly-sanctioned-by: jkh
The driver constructs a fake disklabel that makes the 'a' partition
cover the entire DVD-RAM disk. This cannot be changed from the user
side. This solution was chosen because most DVD-RAM will have a
UDF (or until we have that CD9660) filesystem on it covering the
entire disk, its not really thought as a real random access device.
This might change over time, but for now this is what we have, and
it is compatible with CDROM's etc, that makes using the minidisk
subsystem less than ideal, because of !modulo BDEV_SIZE blocks.