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2009-03-24UIO: Take offset into account when determining number of pages that can be ↵Ian Abbott
mapped If a UIO memory region does not start on a page boundary but straddles one, the number of actual pages that overlap the memory region may be calculated incorrectly because the offset isn't taken into account. If userspace sets the mmap length to offset+size, it may fail with -EINVAL if UIO thinks it's trying to allocate too many pages. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Cc: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24UIO: Add name attributes for mappings and port regionsHans J. Koch
If a UIO device has several memory mappings, it can be difficult for userspace to find the right one. The situation becomes even worse if the UIO driver can handle different versions of a card that have different numbers of mappings. Benedikt Spranger has such cards and pointed this out to me. Thanks, Bene! To address this problem, this patch adds "name" sysfs attributes for each mapping. Userspace can use these to clearly identify each mapping. The name string is optional. If a driver doesn't set it, an empty string will be returned, so this patch won't break existing drivers. The same problem exists for port region information, so a "name" attribute is added there, too. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06UIO: Pass information about ioports to userspace (V2)Hans J. Koch
Devices sometimes have memory where all or parts of it can not be mapped to userspace. But it might still be possible to access this memory from userspace by other means. An example are PCI cards that advertise not only mappable memory but also ioport ranges. On x86 architectures, these can be accessed with ioperm, iopl, inb, outb, and friends. Mike Frysinger (CCed) reported a similar problem on Blackfin arch where it doesn't seem to be easy to mmap non-cached memory but it can still be accessed from userspace. This patch allows kernel drivers to pass information about such ports to userspace. Similar to the existing mem[] array, it adds a port[] array to struct uio_info. Each port range is described by start, size, and porttype. If a driver fills in at least one such port range, the UIO core will simply pass this information to userspace by creating a new directory "portio" underneath /sys/class/uio/uioN/. Similar to the "mem" directory, it will contain a subdirectory (portX) for each port range given. Note that UIO simply passes this information to userspace, it performs no action whatsoever with this data. It's userspace's responsibility to obtain access to these ports and to solve arch dependent issues. The "porttype" attribute tells userspace what kind of port it is dealing with. This mechanism could also be used to give userspace information about GPIOs related to a device. You frequently find such hardware in embedded devices, so I added a UIO_PORT_GPIO definition. I'm not really sure if this is a good idea since there are other solutions to this problem, but it won't hurt much anyway. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-11-01saner FASYNC handling on file closeAl Viro
As it is, all instances of ->release() for files that have ->fasync() need to remember to evict file from fasync lists; forgetting that creates a hole and we actually have a bunch that *does* forget. So let's keep our lives simple - let __fput() check FASYNC in file->f_flags and call ->fasync() there if it's been set. And lose that crap in ->release() instances - leaving it there is still valid, but we don't have to bother anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6Linus Torvalds
* 'bkl-removal' of git://git.lwn.net/linux-2.6: UIO: BKL removal
2008-10-16UIO: BKL removalJonathan Corbet
Fill in needed locking around idr accesses, then remove the big kernel lock from the UIO driver. Since there are no in-tree UIO drivers with open() methods, no further BKL pushdown is required. Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-10-16UIO: Fix mapping of logical and virtual memoryAndrew G. Harvey
mmap() doesn't work as expected for UIO_MEM_LOGICAL or UIO_MEM_VIRTUAL mappings. The offset into the memory needs to be added, otherwise uio_vma_fault always returns the first page only. Note that for UIO userspace calls mmap() with offset = N * getpagesize() to access mapping N. This must be compensated when calculating the offset. A comment was added to explain this since it is not obvious. Signed-off-by: Andrew G. Harvey <agh@cisco.com> Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16UIO: Add alignment warnings for uio-memHans J. Koch
This patch adds an "offset" attribute for UIO mappings. It shows the difference between the actual start address of the memory and the start address of the page. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16device create: misc: convert device_create_drvdata to device_createGreg Kroah-Hartman
Now that device_create() has been audited, rename things back to the original call to be sane. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21UIO: Add write function to allow irq maskingHans J. Koch
Sometimes it is necessary to enable/disable the interrupt of a UIO device from the userspace part of the driver. With this patch, the UIO kernel driver can implement an "irqcontrol()" function that does this. Userspace can write an s32 value to /dev/uioX (usually 0 or 1 to turn the irq off or on). The UIO core will then call the driver's irqcontrol function. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com> Acked-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-14Merge commit 'v2.6.26' into bkl-removalJonathan Corbet
2008-06-20UIO: cdev lock_kernel() pushdownJonathan Corbet
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-05-20UIO: fix race in device_createGreg Kroah-Hartman
There is a race from when a device is created with device_create() and then the drvdata is set with a call to dev_set_drvdata() in which a sysfs file could be open, yet the drvdata will be NULL, causing all sorts of bad things to happen. This patch fixes the problem by using the new function, device_create_drvdata(). Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-19UIO: hold a reference to the device's owner while the device is openUwe Kleine-König
Otherwise the device might just disappear while /dev/uioX is being used which results in an Oops. Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com> Signed-off-by: Hans J Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-24UIO: add pgprot_noncached() to UIO mmap codeJean-Samuel Chenard
Mapping of physical memory in UIO needs pgprot_noncached() to ensure that IO memory is not cached. Without pgprot_noncached(), it (accidentally) works on x86 and arm, but fails on PPC. Signed-off-by: Jean-Samuel Chenard <jsamch@gmail.com> Signed-off-by: Hans J Koch <hjk@linutronix.de> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-21UIO: fix Greg's stupid changesBrandon Philips
This fixes two bugs with UIO that cropped up recently in -rc1 1) WARNING: at fs/sysfs/file.c:334 sysfs_open_file when trying to open a map addr/size file - complaining about missing sysfs_ops for ktype 2) Permission denied when reading uio/uio0/maps/map0/{addr,size} when files are mode S_IRUGO Also fix a typo: attr_attribute -> addr_attribute Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-06uio: nopageNick Piggin
Convert uio from nopage to fault. Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Hans J Koch <hjk@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-24UIO: constify function pointer tablesJan Engelhardt
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Kobject: convert drivers/* from kobject_unregister() to kobject_put()Greg Kroah-Hartman
There is no need for kobject_unregister() anymore, thanks to Kay's kobject cleanup changes, so replace all instances of it with kobject_put(). Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Kobject: rename kobject_init_ng() to kobject_init()Greg Kroah-Hartman
Now that the old kobject_init() function is gone, rename kobject_init_ng() to kobject_init() to clean up the namespace. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Kobject: rename kobject_add_ng() to kobject_add()Greg Kroah-Hartman
Now that the old kobject_add() function is gone, rename kobject_add_ng() to kobject_add() to clean up the namespace. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24UIO: fix kobject usageGreg Kroah-Hartman
The uio kobject code is "wierd". This patch should hopefully fix it up to be sane and not leak memory anymore. Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benedikt Spranger <b.spranger@linutronix.de> Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24kobject: remove struct kobj_type from struct ksetGreg Kroah-Hartman
We don't need a "default" ktype for a kset. We should set this explicitly every time for each kset. This change is needed so that we can make ksets dynamic, and cleans up one of the odd, undocumented assumption that the kset/kobject/ktype model has. This patch is based on a lot of help from Kay Sievers. Nasty bug in the block code was found by Dave Young <hidave.darkstar@gmail.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-18UIO: Add the User IO core codeHans J. Koch
This interface allows the ability to write the majority of a driver in userspace with only a very small shell of a driver in the kernel itself. It uses a char device and sysfs to interact with a userspace process to process interrupts and control memory accesses. See the docbook documentation for more details on how to use this interface. From: Hans J. Koch <hjk@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benedikt Spranger <b.spranger@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>