This is a minor correctness fix: since the at91_cf driver probe() routine
is in the init section, it should use platform_driver_probe() instead of
leaving that pointer around in the driver struct after init section
removal.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This introduce krealloc() that reallocates memory while keeping the contents
unchanged. The allocator avoids reallocation if the new size fits the
currently used cache. I also added a simple non-optimized version for
mm/slob.c for compatibility.
[akpm@linux-foundation.org: fix warnings]
Acked-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Acked-by: Matt Mackall <mpm@selenic.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was broken. It adds complexity, for no good reason. Rather than
separate __pa() and __pa_symbol(), we should deprecate __pa_symbol(),
and preferably __pa() too - and just use "virt_to_phys()" instead, which
is more readable and has nicer semantics.
However, right now, just undo the separation, and make __pa_symbol() be
the exact same as __pa(). That fixes the bugs this patch introduced,
and we can do the fairly obvious cleanups later.
Do the new __phys_addr() function (which is now the actual workhorse for
the unified __pa()/__pa_symbol()) as a real external function, that way
all the potential issues with compile/link-time optimizations of
constant symbol addresses go away, and we can also, if we choose to, add
more sanity-checking of the argument.
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild: (38 commits)
kconfig: fix mconf segmentation fault
kbuild: enable use of code from a different dir
kconfig: error out if recursive dependencies are found
kbuild: scripts/basic/fixdep segfault on pathological string-o-death
kconfig: correct minor typo in Kconfig warning message.
kconfig: fix path to modules.txt in Kconfig help
usr/Kconfig: fix typo
kernel-doc: alphabetically-sorted entries in index.html of 'htmldocs'
kbuild: be more explicit on missing .config file
kbuild: clarify the creation of the LOCALVERSION_AUTO string.
kbuild: propagate errors from find in scripts/gen_initramfs_list.sh
kconfig: refer to qt3 if we cannot find qt libraries
kbuild: handle compressed cpio initramfs-es
kbuild: ignore section mismatch warning for references from .paravirtprobe to .init.text
kbuild: remove stale comment in modpost.c
kbuild/mkuboot.sh: allow spaces in CROSS_COMPILE
kbuild: fix make mrproper for Documentation/DocBook/man
kbuild: remove kconfig binaries during make mrproper
kconfig/menuconfig: do not hardcode '.config'
kbuild: override build timestamp & version
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (66 commits)
KVM: Remove unused 'instruction_length'
KVM: Don't require explicit indication of completion of mmio or pio
KVM: Remove extraneous guest entry on mmio read
KVM: SVM: Only save/restore MSRs when needed
KVM: fix an if() condition
KVM: VMX: Add lazy FPU support for VT
KVM: VMX: Properly shadow the CR0 register in the vcpu struct
KVM: Don't complain about cpu erratum AA15
KVM: Lazy FPU support for SVM
KVM: Allow passing 64-bit values to the emulated read/write API
KVM: Per-vcpu statistics
KVM: VMX: Avoid unnecessary vcpu_load()/vcpu_put() cycles
KVM: MMU: Avoid heavy ASSERT at non debug mode.
KVM: VMX: Only save/restore MSR_K6_STAR if necessary
KVM: Fold drivers/kvm/kvm_vmx.h into drivers/kvm/vmx.c
KVM: VMX: Don't switch 64-bit msrs for 32-bit guests
KVM: VMX: Reduce unnecessary saving of host msrs
KVM: Handle guest page faults when emulating mmio
KVM: SVM: Report hardware exit reason to userspace instead of dmesg
KVM: Retry sleeping allocation if atomic allocation fails
...
utrace removes the ptrace_message field in task_struct. Move our use
of this field into a new member in thread_info called "syscall"
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
I have found small bug in mconf, when you run it without any argument it
will sigsegv.
Without patch:
$ scripts/kconfig/mconf
Segmentation fault
With patch:
$ scripts/kconfig/mconf
can't find file (null)
Signed-off-by: Marcin Garski <mgarski@post.pl>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
To introduce support for source in one directory but output files
in another directory during a non O= build prefix all paths
with $(src) repsectively $(obj).
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Sample:
config FOO
bool "This is foo"
depends on BAR
config BAR
bool "This is bar"
depends on FOO
This will result in following error message:
error: found recursive dependency: FOO -> BAR -> FOO
And will then exit with exit code equal 1 so make will stop.
Inspired by patch from: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Roman Zippel <zippel@linux-m68k.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] Fix typo in cifs readme from previous commit
[CIFS] Make sec=none force an anonymous mount
[CIFS] Change semaphore to mutex for cifs lock_sem
[CIFS] Fix oops in reset_cifs_unix_caps on reconnect
[CIFS] UID/GID override on CIFS mounts to Samba
[CIFS] prefixpath mounts to servers supporting posix paths used wrong slash
[CIFS] Update cifs version to 1.49
[CIFS] Replace kmalloc/memset combination with kzalloc
[CIFS] Add IPv6 support
[CIFS] New CIFS POSIX mkdir performance improvement (part 2)
[CIFS] New CIFS POSIX mkdir performance improvement
[CIFS] Add write perm for usr to file on windows should remove r/o dos attr
[CIFS] Remove unnecessary parm to cifs_reopen_file
[CIFS] Switch cifsd to kthread_run from kernel_thread
[CIFS] Remove unnecessary checks
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (231 commits)
[PATCH] i386: Don't delete cpu_devs data to identify different x86 types in late_initcall
[PATCH] i386: type may be unused
[PATCH] i386: Some additional chipset register values validation.
[PATCH] i386: Add missing !X86_PAE dependincy to the 2G/2G split.
[PATCH] x86-64: Don't exclude asm-offsets.c in Documentation/dontdiff
[PATCH] i386: avoid redundant preempt_disable in __unlazy_fpu
[PATCH] i386: white space fixes in i387.h
[PATCH] i386: Drop noisy e820 debugging printks
[PATCH] x86-64: Fix allnoconfig error in genapic_flat.c
[PATCH] x86-64: Shut up warnings for vfat compat ioctls on other file systems
[PATCH] x86-64: Share identical video.S between i386 and x86-64
[PATCH] x86-64: Remove CONFIG_REORDER
[PATCH] x86-64: Print type and size correctly for unknown compat ioctls
[PATCH] i386: Remove copy_*_user BUG_ONs for (size < 0)
[PATCH] i386: Little cleanups in smpboot.c
[PATCH] x86-64: Don't enable NUMA for a single node in K8 NUMA scanning
[PATCH] x86: Use RDTSCP for synchronous get_cycles if possible
[PATCH] i386: Add X86_FEATURE_RDTSCP
[PATCH] i386: Implement X86_FEATURE_SYNC_RDTSC on i386
[PATCH] i386: Implement alternative_io for i386
...
Fix up trivial conflict in include/linux/highmem.h manually.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It still used the long-deprecated "pci_module_init()" interface, rather
than the proper "pci_register_driver()" one.
[ I don't have the hardware, and I doubt many do, but the fix is
trivial and obvious, and can't be worse than not compiling ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CC fs/nfs/nfsroot.o
fs/nfs/nfsroot.c:131: error: tokens causes a section type conflict
make[2]: *** [fs/nfs/nfsroot.o] Error 1
This is due to mixing const and non-const content in the same section
which halfway recent gccs absolutely hate. Fixed by dropping the const.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* master.kernel.org:/pub/scm/linux/kernel/git/jejb/voyager-2.6:
[VOYAGER] add smp alternatives
[VOYAGER] Use modern techniques to setup and teardown low identiy mappings.
[VOYAGER] Convert the monitor thread to use the kthread API
[VOYAGER] clockevents driver: bring voyager in to line
[VOYAGER] clockevents: correct boot cpu is zero assumption
[VOYAGER] add smp_call_function_single
The S3C2410_UDC_SETIX() macro is not used and won't be used by the udc
driver, so delete it.
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
linux/mmc/protocol.h header is gone, thus breaking the build of the
mach-qt2410.c file. As this header is not used, I'm removing it. The
right headers may still be added later if needed.
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
And fix up the code to always allow MSI on 5714 A2.
Call tg3_find_peer() earlier because we need that information before
we can determine whether we can set TG3_FLAG_SUPPORT_MSI or not.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Without the following patch, the kernel does not automatically detect
2GB CompactFlash cards from Transcend.
Signed-off-by: Fabrice Aeschbacher <fabrice.aeschbacher@siemens.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Peter Stuge <peter@stuge.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
HPT36x chip don't seem to have the channel enable bits, so prevent the IDE core
from checking them...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Michal Kepien <michal.kepien@poczta.onet.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* fix ->speedproc to set the drive speed
* this driver doesn't support SWDMA so use the correct ->swdma_mask
* BUG() if an unsupported mode is passed to ->speedproc
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This driver doesn't support SWDMA so use the correct ->swdma_mask.
While at it:
* no need to call config_chipset_for_pio() in config_chipset_for_dma(),
if DMA is not available config_chipset_for_pio() will be called
by siimage_config_drive_for_dma() and if DMA is available
config_siimage_chipset_for_pio() will be called by siimage_tune_chipset()
* remove needless config_chipset_for_pio() wrapper
* bump driver version
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* limit max PIO mode to PIO4, this driver doesn't support PIO5 and attempt
to setup PIO5 by it821x_tuneproc() could result in incorrect PIO timings
+ incorrect base clock being set for controller in the passthrough mode
* move code limiting max PIO according to the pair device capabilities from
config_it821x_chipset_for_pio() to it821x_tuneproc() so the check is also
applied for mode change requests coming through ->tuneproc and ->speedproc
interfaces
* set device speed in it821x_tuneproc()
* in it821x_tune_chipset() call it821x_tuneproc() also if the controller is
in the smart mode (so the check for pair device max PIO is done)
* rename it821x_tuneproc() to it821x_tune_pio(), then add it821x_tuneproc()
wrapper which does the max PIO mode check; it worked by the pure luck
previously, pio[4] and pio_want[4] arrays were used with index == 255
so random PIO timings and base clock were set for the controller in the
passthrough mode, thankfully PIO timings and base clock were corrected
later by config_it821x_chipset_for_pio() call (but it was not called for
PIO-only devices during resume and for user requested PIO autotuning)
* remove config_it821x_chipset_for_pio() call from config_chipset_for_dma()
as the driver sets ->autotune to 1 and ->tuneproc does the proper job now
* convert the last user of config_it821x_chipset_for_pio() to use
it821x_tuneproc(drive, 255) and remove no longer needed function
While at it:
* fix few comments
* bump driver version
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Teach the driver's tuneproc() method to do PIO auto-runing properly since it
treated 5 instead of 255 as auto-tune request, and also passed the mode limit
of PIO5 to ide_get_best_pio_mode() despite supporting up to PIO4 only.
While at it, also:
- remove the driver's wrong claim about supporting SWDMA modes;
- stop hooking ide_dma_timeout() method as the handler clearly doesn't fit for
the task...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Fold the parts of the ide_dma_end() methods identical to __ide_dma_end() into a
mere call to it.
Start using faster versions of the ide_dma_end() and ide_dma_test_irq() methods
for the PCI0646U and newer chips that have the duplicate interrupt status bits
in the I/O mapped MRDMODE register, determing what methods to use at the driver
load time. Do some cleanup/renaming in the "old" ide_dma_test_irq() method too.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Fix several issues with the driver's procfs output:
- when testing if channel is enabled, the code looks at the "simplex" bits, not
at the real enable bits -- add #define for the primary channel enable bit;
- UltraDMA modes 0, 1, 3 for slave drive reported incorrectly due to using the
master drive's clock cycle resolution bit.
While at it, also perform the following cleanups:
- don't print extra newline before the first controller's dump;
- correct the chipset names (from CMDxxx to PCI-xxx)
- don't read from the registers which aren't used for dump;
- better align the table column sizes;
- rework UltraDMA mode dump code;
- remove PIO mode dump code that has never been finished;
- remove the duplicate interrupt status (the MRDMODE register bits mirror those
those in the CFR and ARTTIM23 registers) and fold the dump into single line;
- correct the style of the ?: operators...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
The IDE core looks at the wrong bit when checking if the secondary channel is
enabled on PCI0646 -- CNTRL register bit 7 is read-ahead disable, bit 3 is the
correct one.
Starting with PCI0646U chip, the primary channel can also be enabled/disabled --
so, add 'enablebits' initializers to each 'ide_pci_device_t' structure, handling
the original PCI0646 via adding the init_setup() method and clearing the 'reg'
field there if necessary...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
The driver's ide_dma_test_irq() method was reading the MRDMODE register even on
PCI0643/6 where it was write-only -- fix this by always reading the "backward-
compatible" interrupt bits, renaming dma_alt_stat to irq_stat as the interrupt
status bits are not coupled to DMA.
In addition, wrong interrupt bit was tested/cleared for the primary channel --
it's bit 2 in all the chip specs and the driver used bit 1... :-/
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Fix the multiword DMA and drop the single-word DMA support (which nobody will
miss, I think). In order to do it, a number of changes was necessary:
- rename program_drive_counts() to program_cycle_times(), pass to it cycle's
total/active times instead of the clock counts, and convert them into the
active/recovery clocks there instead of cmd64x_tune_pio() -- this causes
quantize_timing() to also move;
- contrarywise, move all the code handling the address setup timing into
cmd64x_tune_pio(), so that setting MWDMA mode wouldn't change address setup;
- remove from the speedproc() method the bogus code pretending to set the DMA
timings by twiddling bits in the BMIDE status register, handle setting MWDMA
by just calling program_cycle_times(); while at it, improve the style of that
whole switch statement;
- stop fiddling with the DMA capable bits in the speedproc() method -- they do
not enable DMA, and are properly dealt with by the dma_host_{on,off} methods;
- don't set hwif->swdma_mask in the init_hwif() method anymore.
In addition to those changes, do the following:
- in cmd64x_tune_pio(), when writing to ARTTIM23 register preserve the interrupt
status bit, eliminate local_irq_{save|restore}() around this code as there's
*no* actual race with the interrupt handler, and move cmdprintk() to a more
fitting place -- after ide_get_best_pio_mode() call;
- make {arttim|drwtim}_regs arrays single-dimensional, indexed with drive->dn;
- rename {setup|recovery}_counts[] into more fitting {setup|recovery}_values[];
- in the speedproc() method, get rid of the duplicate reads/writes from/to the
UDIDETCRx registers and of the extra variable used to store the transfer mode
value after filtering, use another method of determining master/slave drive,
and cleanup useless parens;
- beautify cmdprintk() output here and there.
While at it, remove meaningless comment about the driver being used only on
UltraSPARC and long non-relevant RCS tag. :-)
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Fold the now equivalent code in the ide_dma_check() method into a mere call to
ide_use_dma(). Make config_for_dma() return non-zero if DMA mode has been set
and call it from the ide_dma_check() method instead of ide_dma_on().
Defer writing the DMA timings to the chip registers until DMA is really turned
on (and do not enable IORDY for DMA).
Remove unneeded code from the init_hwif() method, improve its overall looks.
Rename the dma_start(), ide_dma_check(), and ide_dma_lostirq() methods, and
also use more proper hwif->dma_command, fix printk() and comment in the latter
one as well. While at it, cleanup style in several places.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Get rid of the 'pio_speed' member of 'ide_drive_t' that was only used by this
driver by storing the PIO mode timings in the 'drive_data' instead -- this
allows us to greatly simplify the process of "reloading" of the chip's timing
register and do it right in sl82c150_dma_off_quietly() and to get rid of two
extra arguments to config_for_pio() -- which got renamed to sl82c105_tune_pio()
and now returns a PIO mode selected, with ide_config_drive_speed() call moved
into the tuneproc() method, now called sl82c105_tune_drive() with the code to
set drive's 'io_32bit' and 'unmask' flags in its turn moved to its proper place
in the init_hwif() method.
Also, while at it, rename get_timing_sl82c105() into get_pio_timings() and get
rid of the code in it clamping cycle counts to 32 which was both incorrect and
never executed anyway...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
__ioremap() took a set of page table flags (specifically the cacheable
and bufferable bits) to control the mapping type. However, with
the advent of ARMv6, this is far too limited.
Replace the page table flags with a memory type index, so that the
desired attributes can be selected from the mem_type table.
Finally, to prevent silent miscompilation due to the differing
arguments, rename the __ioremap() and __ioremap_pfn() functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch removes the use of the TG3_FLAG_5701_REG_WRITE_BUG flag.
It's logic is only used to set a function pointer and thus the
logic can be collapsed and the flag removed.
[ Comment tidy by Christoph Hellwig. -DaveM ]
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Add cached device type for ioremap_cached(). Group all device memory
types together, and ensure that they all have a "MT_DEVICE" prefix.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The reset was added a while back so that ASF could re-init whatever
MAC address it wanted to use after the MAC address was changed.
Instead of resetting, we can just keep MAC address 1 unchanged during
MAC address changes if MAC address 1 is different from MAC address 0.
This fixes 2 problems:
1. Bonding calls set_mac_address in contexts that cannot sleep.
It no longer sleeps with the chip reset removed.
2. When ASF shares the same MAC address as the NIC, it needs to
always do that even when the MAC address is changed.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the memory types table to define the L1 descriptor bit 4 to
be in terms of the ARMv6 definition - execute never.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Change TG3_FLAG_SERDES_WOL_CAP to TG3_FLAG_WOL_CAP to make it easier
to manage WoL. This flag is now used consistently during ethtool WoL
setup and power setting changes.
Signed-off-by: Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The GPIO settings may change during reset and so the stored values in
tp->grc_local_ctrl should be cleared first.
Signed-off-by: Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes the NVRAM sizing procedure so that the driver can
take advantage of devices with 1:1 NVRAM strapping configurations. This
is useful in cases where the traditional NVRAM sizing method fails. In
the event that the flash size cannot be determined, the largest known
NVRAM size is used. The patch also removes support for 5755 NVRAM
devices that are not supported by Broadcom and adds explicit sizing for
this device.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1. Remove the check for skb->len greater than MTU when doing TSO.
When the destination has a smaller MSS than the source, a TSO packet
may be smaller than the MTU and we still need to process it as a TSO
packet.
2. On 5705A3 devices with TSO enabled, the DMA engine can hang due to a
hardware bug. This patch avoids the hanging condition by reducing the
DMA burst size.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add MAINTAINERS entry for mac80211.
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David Brownell
Pekka Enberg
Linus Torvalds
Russell King
Marcin Garski
Sam Ravnborg
Steve French
Ralf Baechle
Arnaud Patard
Michael Chan
Fabrice Aeschbacher
Sergei Shtylyov
Bartlomiej Zolnierkiewicz
Matt Carlson
Gary Zambrano
Jiri Benc