With the new multi zcrypt device node support there came
in a code rework which broke the in-kernel api function
zcrypt_send_cprb(). This function is used by the pkey kernel
module and as an effect, transforming a secure key into a
protected key did not work any more.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The apfs field (AP final status) is set on transport
protocol failures (reply code 0x90) for type 86 replies.
For CCA cprbs this value is copied into the xcrb status
field which gives userspace a hint for the failure reason.
However, for EP11 cprbs there is no such status field
in the xcrb struct. So now regardless of the request
type, if a reply type 86 with transport protocol failure
is seen, the apfs value is printed as part of the debug
message. So the user has a chance to see the apfs value
without using a special build kernel.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some cleanup in the s390 zcrypt device driver:
- Removed fragments of pcixx crypto card code. This code
can't be reached anymore because the hardware detection
function does not recognize crypto cards < CEX2 since
commit f56545430736 ("s390/zcrypt: Introduce QACT support
for AP bus devices.")
- Rename of some files and driver names which where still
reflecting pcixx support to cex2a/cex2c.
- Removed all the zcrypt version strings in the file headers.
There is only one place left - the zcrypt.h header file is
now the only place for zcrypt device driver version info.
- Zcrypt version pump up from 2.2.0 to 2.2.1.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch is an extension to the zcrypt device driver to provide,
support and maintain multiple zcrypt device nodes. The individual
zcrypt device nodes can be restricted in terms of crypto cards,
domains and available ioctls. Such a device node can be used as a
base for container solutions like docker to control and restrict
the access to crypto resources.
The handling is done with a new sysfs subdir /sys/class/zcrypt.
Echoing a name (or an empty sting) into the attribute "create" creates
a new zcrypt device node. In /sys/class/zcrypt a new link will appear
which points to the sysfs device tree of this new device. The
attribute files "ioctlmask", "apmask" and "aqmask" in this directory
are used to customize this new zcrypt device node instance. Finally
the zcrypt device node can be destroyed by echoing the name into
/sys/class/zcrypt/destroy. The internal structs holding the device
info are reference counted - so a destroy will not hard remove a
device but only marks it as removable when the reference counter drops
to zero.
The mask values are bitmaps in big endian order starting with bit 0.
So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
attributes accept 2 different formats:
* Absolute hex string starting with 0x like "0x12345678" does set
the mask starting from left to right. If the given string is shorter
than the mask it is padded with 0s on the right. If the string is
longer than the mask an error comes back (EINVAL).
* Relative format - a concatenation (done with ',') of the
terms +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]. <bitnr> may be any
valid number (hex, decimal or octal) in the range 0...255. Here are
some examples:
"+0-15,+32,-128,-0xFF"
"-0-255,+1-16,+0x128"
"+1,+2,+3,+4,-5,-7-10"
A simple usage examples:
# create new zcrypt device 'my_zcrypt':
echo "my_zcrypt" >/sys/class/zcrypt/create
# go into the device dir of this new device
echo "my_zcrypt" >create
cd my_zcrypt/
ls -l
total 0
-rw-r--r-- 1 root root 4096 Jul 20 15:23 apmask
-rw-r--r-- 1 root root 4096 Jul 20 15:23 aqmask
-r--r--r-- 1 root root 4096 Jul 20 15:23 dev
-rw-r--r-- 1 root root 4096 Jul 20 15:23 ioctlmask
lrwxrwxrwx 1 root root 0 Jul 20 15:23 subsystem -> ../../../../class/zcrypt
...
# customize this zcrypt node clone
# enable only adapter 0 and 2
echo "0xa0" >apmask
# enable only domain 6
echo "+6" >aqmask
# enable all 256 ioctls
echo "+0-255" >ioctls
# now the /dev/my_zcrypt may be used
# finally destroy it
echo "my_zcrypt" >/sys/class/zcrypt/destroy
Please note that a very similar 'filtering behavior' also applies to
the parent z90crypt device. The two mask attributes apmask and aqmask
in /sys/bus/ap act the very same for the z90crypt device node. However
the implementation here is totally different as the ap bus acts on
bind/unbind of queue devices and associated drivers but the effect is
still the same. So there are two filters active for each additional
zcrypt device node: The adapter/domain needs to be enabled on the ap
bus level and it needs to be active on the zcrypt device node level.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Code beautify by following most of the checkpatch suggestions:
- SPDX license identifier line complains by checkpatch
- missing space or newline complains by checkpatch
- octal numbers for permssions complains by checkpatch
- renaming of static sysfs functions complains by checkpatch
- fix of block comment complains by checkpatch
- fix printf like calls where function name instead of %s __func__
was used
- __packed instead of __attribute__((packed))
- init to zero for static variables removed
- use of DEVICE_ATTR_RO and DEVICE_ATTR_RW macros
No functional code changes or API changes!
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Tests showed, that the zcrypt device driver produces memory
leaks when a valid CCA or EP11 CPRB can't get delivered or has
a failure during processing within the zcrypt device driver.
This happens when a invalid domain or adapter number is used
or the lower level software or hardware layers produce any
kind of failure during processing of the request.
Only CPRBs send to CCA or EP11 cards can produce this memory
leak. The accelerator and the CPRBs processed by this type
of crypto card is not affected.
The two fields message and private within the ap_message struct
are allocated with pulling the function code for the CPRB but
only freed when processing of the CPRB succeeds. So for example
an invalid domain or adapter field causes the processing to
fail, leaving these two memory areas allocated forever.
Signed-off-by: Harald Freudenberger <freude@de.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There was an artificial restriction on the card/adapter id
to only 6 bits but all the AP commands do support adapter
ids with 8 bit. This patch removes this restriction to 64
adapters and now up to 256 adapter can get addressed.
Some of the ioctl calls work on the max number of cards
possible (which was 64). These ioctls are now deprecated
but still supported. All the defines, structs and ioctl
interface declarations have been kept for compabibility.
There are now new ioctls (and defines for these) with an
additional '2' appended which provide the extended versions
with 256 cards supported.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch removes the deprecated zcrypt proc interface.
It is outdated and deprecated and does not support the
latest 3 generations of CEX cards.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch removes the old status calls which have been marked
as deprecated since at least 2 years now. There is no known
application or library relying on these ioctls any more.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that the SPDX tag is in all drivers/s390/crypto/ files, that
identifies the license in a specific and legally-defined manner. So the
extra GPL text wording can be removed as it is no longer needed at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
No copyright headers or other non-license-description text was removed.
Cc: Harald Freudenberger <freude@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the drivers/s390/crypto/ files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Harald Freudenberger <freude@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The function to decide if one zcrypt queue is better than
another one compared two pointers instead of comparing the
values where the pointers refer to. So within the same
zcrypt card when load of each queue was equal just one queue
was used. This effect only appears on relatively lite load,
typically with one thread applications.
This patch fixes the wrong comparison and now the counters
show that requests are balanced equally over all available
queues within the cards.
There is no performance improvement coming with this fix.
As long as the queue depth for an APQN queue is not touched,
processing is not faster when requests are spread over
queues within the same card hardware. So this fix only
beautifies the lszcrypt counter printouts.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On some debug feature invocations the newline was missing.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Added some dbf debug messages on failure of the most important
ioctl calls. These messages are only enabled with dbf level
6 (debug) and so do not affect the normal operating mode which
uses level 3 (errors and higher).
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Export the two zcrypt device driver functions zcrypt_send_cprb and
zcrypt_device_status_mask to be useable for other kernel code.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The ap bus code and the zcrypt api had invocations to the
debug feature debugfs_create_dir() call but never populated
these directories in any way. Removed this unneeded code.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
During tests the Kernel complained about inconsistend lock state:
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
Now all the queue locks use spin_lock_bh/spin_unlock_bh.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Yet another trivial patch to reduce the noise that coccinelle
generates.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch introduces tracepoint definitions and tracepoint
event invocations for the s390 zcrypt device.
Currently there are just two tracepoint events defined.
An s390_zcrypt_req request event occurs as soon as the
request is recognized by the zcrypt ioctl function. This
event may act as some kind of request-processing-starts-now
indication.
As late as possible within the zcrypt ioctl function there
occurs the s390_zcrypt_rep event which may act as the point
in time where the request has been processed by the kernel
and the result is about to be transferred back to userspace.
The glue which binds together request and reply event is the
ptr parameter, which is the local buffer address where the
request from userspace has been stored by the ioctl function.
The main purpose of this zcrypt tracepoint patch is to get
some data for performance measurements together with
information about the kind of request and on which card and
queue the request has been processed. It is not an ffdc
interface as there is already code in the zcrypt device
driver to serve the s390 debug feature interface.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Rework the debug feature calls and initialization. There
are now two debug feature entries used by the zcrypt code.
The first is 'ap' with all the AP bus related stuff and the
second is 'zcrypt' with all the zcrypt and devices and
driver related entries. However, there isn't much traffic on
both debug features. The ap bus code emits only some debug
info and for zcrypt devices on appearance and disappearance
there is an entry written.
The new dbf invocations use the sprintf buffer layout,
whereas the old implementation used the ascii dbf buffer.
There are now 5*8=40 bytes used for each entry, resulting in
5 parameters per call. As the sprintf buffer needs a format
string the first parameter provides this and so up to 4 more
parameters can be used. Alltogehter the new layout should be
much more human readable for customers and test.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For the older CEX2x and CEX3x cards the function bits returned
by TAPQ do not reflect the functions of the card. Instead the
functionality is implicit by the type of the card. The reworked
zcrypt requires to have the function bits set correct, so this
patch fixes this. The queue selection is not only based on these
function bits but also on function pointers set by the individual
drivers.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the first eligible AP adapter respectively domain will be
selected to service requests. In case of sequential workload, the
very same adapter/domain will be used.
The adapter/domain selection algorithm now considers the completed
transactions per adaper/domain and therefore ensures a homogeneous
utilization.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce new ioctl (ZDEVICESTATUS) to provide detailed
information, like hardware type, domains, status and functionality
of available crypto devices.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the ap infrastructure only supports one domain at a time.
This feature extends the generic cryptographic device driver to
support multiple cryptographic domains simultaneously.
There are now card and queue devices on the AP bus with independent
card and queue drivers. The new /sys layout is as follows:
/sys/bus/ap
devices
<xx>.<yyyy> -> ../../../devices/ap/card<xx>/<xx>.<yyyy>
...
card<xx> -> ../../../devices/ap/card<xx>
...
drivers
<drv>card
card<xx> -> ../../../../devices/ap/card<xx>
<drv>queue
<xx>.<yyyy> -> ../../../../devices/ap/card<xx>/<xx>.<yyyy>
...
/sys/devices/ap
card<xx>
<xx>.<yyyy>
driver -> ../../../../bus/ap/drivers/<zzz>queue
...
driver -> ../../../bus/ap/drivers/<drv>card
...
The two digit <xx> field is the card number, the four digit <yyyy>
field is the queue number and <drv> is the name of the device driver,
e.g. "cex4".
For compatability /sys/bus/ap/card<xx> for the old layout has to exist,
including the attributes that used to reside there.
With additional contributions from Harald Freudenberger and
Martin Schwidefsky.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Crypto requests are very different in complexity and thus runtime.
Also various crypto adapters are differ with regard to the execution
time. Crypto requests can be balanced much better when the request
type and eligible crypto adapters are rated in a more precise
granularity. Therefore, request weights and adapter speed rates for
dedicated requests will be introduced.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that the message type modules are linked with the zcrypt_api
into a single module the zcrypt_ops_list is initialized by
the module init function of the zcyppt.ko module. After that
the list is static and all message types are present.
Drop the zcrypt_ops_list_lock spinlock and the module handling
in regard to the message types.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move the ap bus into the kernel and make it general available.
Additionally include the message types and the API layer as a
preparation for the workload management facility.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The debug_unregister() function performs also input parameter validation.
Thus the test around the calls is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ap_bus and zcrypt_api assumed module information to always be present
and initialisation to be done in module loading order (symbol
dependencies). These assumptions don't hold if zcrypt is built-in;
THIS_MODULE will be NULL in this case and init call order is linker
order, i.e. Makefile order.
Fix initialisation order by ordering the object files in the Makefile
according to their dependencies, like the module loader would do.
Fix message type registration by using a dedicated "name" field rather
than piggy-backing on the module ("owner") information. There's no
change to the requirement that module name and msgtype name are
identical. The existing name macros are used.
We don't need any special code for dealing with the drivers being
built-in; the generic module support code already does the right
thing.
Test results:
1. CONFIG_MODULES=y, CONFIG_ZCRYPT=y
KVM: boots, no /sys/bus/ap (expected)
LPAR with CEX5: boots, /sys/bus/ap/devices/card*/type present
2. CONFIG_MODULES=y, CONFIG_ZCRYPT=m=:
KVM: boots, loading zcrypt_cex4 (and ap) fails (expected)
LPAR with CEX5: boots, loading =zcrypt_cex4= succeeds,
/sys/bus/ap/devices/card*/type present after explicit module
loading
3. CONFIG_MODULES unset, CONFIG_ZCRYPT=y:
KVM: boots, no /sys/bus/ap (expected)
LPAR with CEX5: boots, /sys/bus/ap/devices/card*/type present
No further testing (user-space functionality) was done.
Fixes: 3b6245fd303f ("s390/zcrypt: Separate msgtype implementation from card modules.")
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In the past only even modulus sizes were allowed for RSA keys in
CRT format. This restriction was based on limited RSA key generation
on older crypto adapters that provides only even modulus sizes. This
restriction is not valid any more.
Revoke restrictions that crypto requests can be serviced with odd
RSA modulus length in CRT format.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Set the 'quality' property in the zcrypt rng device structure to enable the
zcrypt hwrng device to take part in the kernel entropy seeding process.
A module parameter named hwrng_seed will be introduced to disable the
participation. By default this parameter is set to 1 (enabled).
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This makes sure format strings can't accidentally leak into kernel
interface names.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This feature extends the generic cryptographic device driver (zcrypt)
with a new capability to service EP11 requests for the Crypto Express4S
card in EP11 (Enterprise PKCS#11 mode) coprocessor mode.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Detect external AP bus configuration changes and request
an AP device rescan.
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Msgtype implementations are now separated from card specific modules
and can be dynamically registered. Existing msgtype implementations
are restructured in modules.
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.
Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Remove the option to build a single module z90crypt that contains
ap bus, request router and card drivers.
Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Also process 4096 bit RSA keys in CRT format. Handle them like the
smaller keys and take care of the zero padding.
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Use nonseekable_open for a couple of s390 device drivers. This avoids
the use of default_llseek function which has a dependency on the BKL.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
It's not obvious that copy_from_user() is called with a sane length
parameter here. Even though it currently seems to be correct better
add a check to prevent stack corruption / exploits.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Harald Freudenberger