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path: root/drivers/char/mem.c
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2007-01-22Revert "[PATCH] Fix up mmap_kmem"Linus Torvalds
This reverts commit 99a10a60ba9bedcf5d70ef81414d3e03816afa3f. As per Hugh Dickins: "Nadia Derbey has reported that mmap of /dev/kmem no longer works with the kernel virtual address as offset, and Franck has confirmed that his patch came from a misunderstanding of what an offset means to /dev/kmem - whereas his patch description seems to say that he was correcting the offset on a few plaforms, there was no such problem to correct, and his patch was in fact changing its API on all platforms." Suggested-by: Hugh Dickins <hugh@veritas.com> Cc: Franck Bui-Huu <fbuihuu@gmail.com> Cc: Nadia Derbey <Nadia.Derbey@bull.net> Cc: Andi Kleen <ak@suse.de> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-10[PATCH] read_zero_pagealigned() locking fixHugh Dickins
Ramiro Voicu hits the BUG_ON(!pte_none(*pte)) in zeromap_pte_range: kernel bugzilla 7645. Right: read_zero_pagealigned uses down_read of mmap_sem, but another thread's racing read of /dev/zero, or a normal fault, can easily set that pte again, in between zap_page_range and zeromap_page_range getting there. It's been wrong ever since 2.4.3. The simple fix is to use down_write instead, but that would serialize reads of /dev/zero more than at present: perhaps some app would be badly affected. So instead let zeromap_page_range return the error instead of BUG_ON, and read_zero_pagealigned break to the slower clear_user loop in that case - there's no need to optimize for it. Use -EEXIST for when a pte is found: BUG_ON in mmap_zero (the other user of zeromap_page_range), though it really isn't interesting there. And since mmap_zero wants -EAGAIN for out-of-memory, the zeromaps better return that than -ENOMEM. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Ramiro Voicu: <Ramiro.Voicu@cern.ch> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] struct path: convert char-driversJosef Sipek
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-01Driver core: change mem class_devices to be real devicesGreg Kroah-Hartman
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-13Include proper header file for PFN_DOWN()Linus Torvalds
The recent commit (99a10a60ba9bedcf5d70ef81414d3e03816afa3f) to fix up mmap_kmem() broke compiles because it used PFN_DOWN() without including <linux/pfn.h>. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-13[PATCH] Fix up mmap_kmemFranck Bui-Huu
vma->vm_pgoff is an pfn _offset_ relatif to the begining of the memory start. The previous code was doing at first: vma->vm_pgoff << PAGE_SHIFT which results into a wrong physical address since some platforms have a physical mem start that can be different from 0. After that the previous call __pa() on this wrong physical address, however __pa() is used to convert a _virtual_ address into a physical one. This patch rewrites this convertion. It calculates the pfn of PAGE_OFFSET which is the pfn of the mem start then it adds the vma->vm_pgoff to it. It also uses virt_to_phys() instead of __pa() since the latter shouldn't be used by drivers. Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] mem driver: fix conditional on isa i/o supportGeoff Levand
This change corrects the logic on the preprocessor conditionals that include support for ISA port i/o (/dev/ioports) into the mem character driver. This fixes the following error when building for powerpc platforms with CONFIG_PCI=n. drivers/built-in.o: undefined reference to `pci_io_base' Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Linas Vepstas <lins@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmemDavid Howells
Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] make valid_mmap_phys_addr_range() take a pfnLennert Buytenhek
Newer ARMs have a 40 bit physical address space, but mapping physical memory above 4G needs a special page table format which we (currently?) do not use for userspace mappings, so what happens instead is that mapping an address >= 4G will happily discard the upper bits and wrap. There is a valid_mmap_phys_addr_range() arch hook where we could check for >= 4G addresses and deny the mapping, but this hook takes an unsigned long address: static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size); And drivers/char/mem.c:mmap_mem() calls it like this: static int mmap_mem(struct file * file, struct vm_area_struct * vma) { size_t size = vma->vm_end - vma->vm_start; if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size)) So that's not much help either. This patch makes the hook take a pfn instead of a phys address. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] make more file_operation structs staticArjan van de Ven
Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-26[PATCH] devfs: Remove the devfs_fs_kernel.h file from the treeGreg Kroah-Hartman
Also fixes up all files that #include it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel treeGreg Kroah-Hartman
Removes the devfs_mk_cdev() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-04-26[PATCH] splice: add ->splice_write support for /dev/nullJens Axboe
Useful for testing. Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-28[PATCH] mark f_ops const in the inodeArjan van de Ven
Mark the f_ops members of inodes as const, as well as fix the ripple-through this causes by places that copy this f_ops and then "do stuff" with it. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26[PATCH] EFI, /dev/mem: simplify efi_mem_attribute_range()Bjorn Helgaas
Pass the size, not a pointer to the size, to efi_mem_attribute_range(). This function validates memory regions for the /dev/mem read/write/mmap paths. The pointer allows arches to reduce the size of the range, but I think that's unnecessary complexity. Simplifying it will let me use efi_mem_attribute_range() to improve the ia64 ioremap() implementation. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Matt Domsch <Matt_Domsch@dell.com> Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com> Cc: "Brown, Len" <len.brown@intel.com> Cc: Andi Kleen <ak@muc.de> Acked-by: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25[PATCH] adjust /dev/{kmem,mem,port} write handlersJan Beulich
The /dev/mem and /dev/kmem write handlers weren't fully POSIX compliant in that they wouldn't always force the file pointer to be updated when returning success status. The /dev/port write handler was inconsistent with the /dev/mem and /dev/kmem handlers in that when encountering a -EFAULT condition after already having written a number of items it would return -EFAULT rather than the number of bytes written. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12[PATCH] powerpc: iSeries fixes for build with no PCIStephen Rothwell
This reverts part of "ppc64 iSeries: allow build with no PCI" (145d01e4287b8cbf50f87c3283e33bf5c84e8468) which affected generic code and applies a fix in the arch specific code. Commit "partly merge iseries do_IRQ" (5fee9b3b39eb55c7e3619a3b36ceeabffeb8f144) introduced iSeries_get_irq which was only available if CONFIG_PCI is set. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-09[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_semJes Sorensen
This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-08[PATCH] /dev/mem: validate mmap requestsBjorn Helgaas
Add a hook so architectures can validate /dev/mem mmap requests. This is analogous to validation we already perform in the read/write paths. The identity mapping scheme used on ia64 requires that each 16MB or 64MB granule be accessed with exactly one attribute (write-back or uncacheable). This avoids "attribute aliasing", which can cause a machine check. Sample problem scenario: - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K - efi_memmap_init() discards any write-back (WB) memory in the first granule - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0 - hwinfo receives UC mapping (the default, since memmap says "no WB here") - Machine check abort (on chipsets that don't support UC access to WB memory, e.g., sx1000) In the scenario above, the only choices are - Use WB for hwinfo mmap. Can't do this because it causes attribute aliasing with the UC mapping for the VGA MMIO space. - Use UC for hwinfo mmap. Can't do this because the chipset may not support UC for that region. - Disallow the hwinfo mmap with -EINVAL. That's what this patch does. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08[PATCH] /dev/mem __HAVE_PHYS_MEM_ACCESS_PROT tidy-upBjorn Helgaas
Tidy up __HAVE_PHYS_MEM_ACCESS_PROT usage to make mmap_mem() easier to read. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08[PATCH] kmsg_write: don't return printk return valueGuillaume Chazarain
kmsg_write returns with printk, so some programs may be confused by a successful write() with a return value different than the buffer length. # /bin/echo something > /dev/kmsg /bin/echo: write error: Inappropriate ioctl for device The drawbacks is that the printk return value can no more be quickly checked from userspace. Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28mm: re-architect the VM_UNPAGED logicLinus Torvalds
This replaces the (in my opinion horrible) VM_UNMAPPED logic with very explicit support for a "remapped page range" aka VM_PFNMAP. It allows a VM area to contain an arbitrary range of page table entries that the VM never touches, and never considers to be normal pages. Any user of "remap_pfn_range()" automatically gets this new functionality, and doesn't even have to mark the pages reserved or indeed mark them any other way. It just works. As a side effect, doing mmap() on /dev/mem works for arbitrary ranges. Sparc update from David in the next commit. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22[PATCH] unpaged: ZERO_PAGE in VM_UNPAGEDHugh Dickins
It's strange enough to be looking out for anonymous pages in VM_UNPAGED areas, let's not insert the ZERO_PAGE there - though whether it would matter will depend on what we decide about ZERO_PAGE refcounting. But whereas do_anonymous_page may (exceptionally) be called on a VM_UNPAGED area, do_no_page should never be: just BUG_ON. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-31Merge ../linux-2.6 by handPaul Mackerras
2005-10-29[PATCH] ppc: make phys_mem_access_prot() work with pfns instead of addressesRoland Dreier
Change the phys_mem_access_prot() function to take a pfn instead of an address. This allows mmap64() to work on /dev/mem for addresses above 4G on 32-bit architectures. We start with a pfn in mmap_mem(), so there's no need to convert to an address; in fact, it's actively bad, since the conversion can overflow when the address is above 4G. Similarly fix the ppc32 page_is_ram() function to avoid a conversion to an address by directly comparing to max_pfn. Working with max_pfn instead of high_memory fixes page_is_ram() to give the right answer for highmem pages. Signed-off-by: Roland Dreier <rolandd@cisco.com> Cc: Anton Blanchard <anton@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28[PATCH] Driver Core: fix up all callers of class_device_create()Greg Kroah-Hartman
The previous patch adding the ability to nest struct class_device changed the paramaters to the call class_device_create(). This patch fixes up all in-kernel users of the function. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-07[PATCH] remove a dead extern in mem.cChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-13Fix up mmap of /dev/kmemLinus Torvalds
This leaves the issue of whether we should deprecate the whole thing (or if we should check the whole mmap range, for that matter) open. Just do the minimal fix for now.
2005-06-25[PATCH] kexec code cleanupManeesh Soni
o Following patch provides purely cosmetic changes and corrects CodingStyle guide lines related certain issues like below in kexec related files o braces for one line "if" statements, "for" loops, o more than 80 column wide lines, o No space after "while", "for" and "switch" key words o Changes: o take-2: Removed the extra tab before "case" key words. o take-3: Put operator at the end of line and space before "*/" Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] kdump: cleanups for dump file access in linear raw formatVivek Goyal
Removed the dependency on backup region. Now all the information is encoded in ELF format. /dev/oldmem is a dummy interface. User space tool need to be intelligent enough to parse the elf headers and read the relevant memory areas with the help of /dev/oldmem. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] kdump: Accessing dump file in linear raw format (/dev/oldmem)Vivek Goyal
Hariprasad Nellitheertha <hari@in.ibm.com> This patch contains the code that enables us to access the previous kernel's memory as /dev/oldmem. Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] ppc64 iSeries: allow build with no PCIStephen Rothwell
This patch allows iSeries to build with CONFIG_PCI=n. This is useful for partitions that have only virtual I/O. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-20[PATCH] class: convert drivers/char/* to use the new class api instead of ↵gregkh@suse.de
class_simple Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!