aboutsummaryrefslogtreecommitdiffstats
path: root/samples/kfifo/inttype-example.c (unfollow)
AgeCommit message (Collapse)AuthorFilesLines
2010-10-15llseek: automatically add .llseek fopArnd Bergmann1-0/+1
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>
2010-09-16libfs: use generic_file_llseek for simple_attrArnd Bergmann1-0/+1
Simple attribute files need to be seekable to allow resetting the file for another read. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16mac80211: disallow seeks in minstrel debug codeArnd Bergmann1-1/+2
No need for seek here, so let's just use nonseekable_open. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16lirc: make chardev nonseekableArnd Bergmann4-0/+5
There does not seem to be a need for lirc to allow seeking on the file descriptor, so let's just disallow this before users start relying on it. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16viotape: use noop_llseekArnd Bergmann1-0/+1
Some applications try to seek on tape devices and fail if they return an error. Since we want to change the default llseek action to no_llseek, viotape needs to be changed to use noop_llseek explicitly. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16raw: use explicit llseek file operationsArnd Bergmann1-0/+2
The raw_fops may need to seek, so there should be an explicit reference to default_llseek. raw_ctl_fops does not contain a read or write method, so we use noop_llseek to ignore seeking requests without an error. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16ibmasmfs: use generic_file_llseekArnd Bergmann1-0/+4
The default for llseek will change to no_llseek, so ibmasmfs needs to add explicit .llseek assignments. Since we're dealing with regular files from a VFS perspective, use generic_file_llseek. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16spufs: use llseek in all file operationsArnd Bergmann1-0/+18
The default for llseek is changing, so we need explicit operations everywhere. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: linuxppc-dev@ozlabs.org
2010-09-16arm/omap: use generic_file_llseek in iommu_debugArnd Bergmann1-0/+2
In future kernels, debugfs files need to specify the llseek operation explicitly to allow seeking. This sets the llseek operation in the omap iommu debugfs files to generic_file_llseek, which is appropriate for files using simple_read_from_buffer. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Tony Lindgren <tony@atomide.com> Cc: linux-omap@vger.kernel.org
2010-09-16lkdtm: use generic_file_llseek in debugfsArnd Bergmann1-0/+9
When the default llseek behavior gets changed to not allowing seek, all file operations that rely on the current behaviour need to use an explicit .llseek operation. The files that lkdtm uses in debugfs are regular files and they get read using simple_read_from_buffer, so generic_file_llseek is the right operation. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-09-16net/wireless: use generic_file_llseek in debugfsArnd Bergmann13-0/+22
The default llseek operation is changing from default_llseek to no_llseek, so all code relying on the current behaviour needs to make that explicit. The wireless driver infrastructure and some of the drivers make use of generated debugfs files, so they cannot be converted by our script that automatically determines the right operation. All these files use debugfs and they typically rely on simple_read_from_buffer, so the best llseek operation here is generic_file_llseek. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org
2010-09-16drm: use noop_llseekArnd Bergmann13-0/+13
The drm device drivers currently allow seeking on the character device but never care about the actual file position. When we change the default llseek operation to be no_llseek, calling llseek on a drm device would return an error condition, which is an API change. Explicitly setting noop_llseek lets us keep the current API. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: David Airlie <airlied@linux.ie> Cc: dri-devel@lists.freedesktop.org
2010-09-12Linux 2.6.36-rc4Linus Torvalds1-1/+1
2010-09-11docbook: skip files with no docs since they generate scary warningsRandy Dunlap2-2/+0
Fix docbook templates that reference files that do not contain the expected kernel-doc notation. Fixes these warnings: Warning(arch/x86/include/asm/unaligned.h): no structured comments found Warning(lib/vsprintf.c): no structured comments found These cause errors in the generated html output, like below, so drop these lines. Name arch/x86/include/asm/unaligned.h - Document generation inconsistency Oops Warning The template for this document tried to insert the structured comment from the file arch/x86/include/asm/unaligned.h at this point, but none was found. This dummy section is inserted to allow generation to continue. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-11docbook: warn on unused doc entriesJohannes Berg3-3/+183
When you don't use !E or !I but only !F, then it's very easy to miss including some functions, structs etc. in documentation. To help finding which ones were missed, allow printing out the unused ones as warnings. For example, using this on mac80211 yields a lot of warnings like this: Warning: didn't use docs for DOC: mac80211 workqueue Warning: didn't use docs for ieee80211_max_queues Warning: didn't use docs for ieee80211_bss_change Warning: didn't use docs for ieee80211_bss_conf when generating the documentation for it. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-11kernel-doc: ignore case when stripping attributesJohannes Berg1-1/+1
There are valid attributes that could have upper case letters, but we still want to remove, like for example __attribute__((aligned(NETDEV_ALIGN))) as encountered in the wireless code. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-11PM / Hibernate: Avoid hitting OOM during preallocation of memoryRafael J. Wysocki1-20/+65
There is a problem in hibernate_preallocate_memory() that it calls preallocate_image_memory() with an argument that may be greater than the total number of available non-highmem memory pages. If that's the case, the OOM condition is guaranteed to trigger, which in turn can cause significant slowdown to occur during hibernation. To avoid that, make preallocate_image_memory() adjust its argument before calling preallocate_image_pages(), so that the total number of saveable non-highem pages left is not less than the minimum size of a hibernation image. Change hibernate_preallocate_memory() to try to allocate from highmem if the number of pages allocated by preallocate_image_memory() is too low. Modify free_unnecessary_pages() to take all possible memory allocation patterns into account. Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: M. Vefa Bicakci <bicave@superonline.com>
2010-09-11x86, tsc: Fix a preemption leak in restore_sched_clock_state()Peter Zijlstra1-1/+1
Doh, a real life genuine preemption leak.. This caused a suspend failure. Reported-bisected-and-tested-by-the-invaluable: Jeff Chua <jeff.chua.linux@gmail.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Nico Schottelius <nico-linux-20100709@schottelius.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Florian Pritz <flo@xssn.at> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: <stable@kernel.org> # Greg, please apply after: cd7240c ("x86, tsc, sched: Recompute cyc2ns_offset's during resume from") sleep states LKML-Reference: <1284150773.402.122.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-10x86, tsc: Fix a preemption leak in restore_sched_clock_state()Peter Zijlstra1-1/+1
A real life genuine preemption leak.. Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-11PM QoS: Correct pr_debug() misuse and improve parameter checksmark gross1-1/+3
Correct some pr_debug() misuse and add a stronger parameter check to pm_qos_write() for the ASCII hex value case. Thanks to Dan Carpenter for pointing out the problem! Signed-off-by: mark gross <markgross@thegnar.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-09-10xfs: log IO completion workqueue is a high priority queueDave Chinner1-1/+2
The workqueue implementation in 2.6.36-rcX has changed, resulting in the workqueues no longer having dedicated threads for work processing. This has caused severe livelocks under heavy parallel create workloads because the log IO completions have been getting held up behind metadata IO completions. Hence log commits would stall, memory allocation would stall because pages could not be cleaned, and lock contention on the AIL during inode IO completion processing was being seen to slow everything down even further. By making the log Io completion workqueue a high priority workqueue, they are queued ahead of all data/metadata IO completions and processed before the data/metadata completions. Hence the log never gets stalled, and operations needed to clean memory can continue as quickly as possible. This avoids the livelock conditions and allos the system to keep running under heavy load as per normal. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-09-10execve: make responsive to SIGKILL with large argumentsRoland McGrath1-0/+7
An execve with a very large total of argument/environment strings can take a really long time in the execve system call. It runs uninterruptibly to count and copy all the strings. This change makes it abort the exec quickly if sent a SIGKILL. Note that this is the conservative change, to interrupt only for SIGKILL, by using fatal_signal_pending(). It would be perfectly correct semantics to let any signal interrupt the string-copying in execve, i.e. use signal_pending() instead of fatal_signal_pending(). We'll save that change for later, since it could have user-visible consequences, such as having a timer set too quickly make it so that an execve can never complete, though it always happened to work before. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10execve: improve interactivity with large argumentsRoland McGrath1-0/+2
This adds a preemption point during the copying of the argument and environment strings for execve, in copy_strings(). There is already a preemption point in the count() loop, so this doesn't add any new points in the abstract sense. When the total argument+environment strings are very large, the time spent copying them can be much more than a normal user time slice. So this change improves the interactivity of the rest of the system when one process is doing an execve with very large arguments. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10setup_arg_pages: diagnose excessive argument sizeRoland McGrath1-0/+5
The CONFIG_STACK_GROWSDOWN variant of setup_arg_pages() does not check the size of the argument/environment area on the stack. When it is unworkably large, shift_arg_pages() hits its BUG_ON. This is exploitable with a very large RLIMIT_STACK limit, to create a crash pretty easily. Check that the initial stack is not too large to make it possible to map in any executable. We're not checking that the actual executable (or intepreter, for binfmt_elf) will fit. So those mappings might clobber part of the initial stack mapping. But that is just userland lossage that userland made happen, not a kernel problem. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10KEYS: Fix bug in keyctl_session_to_parent() if parent has no session keyringDavid Howells1-1/+2
Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership of the parent process's session keyring whether or not the parent has a session keyring [CVE-2010-2960]. This results in the following oops: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0 IP: [<ffffffff811ae4dd>] keyctl_session_to_parent+0x251/0x443 ... Call Trace: [<ffffffff811ae2f3>] ? keyctl_session_to_parent+0x67/0x443 [<ffffffff8109d286>] ? __do_fault+0x24b/0x3d0 [<ffffffff811af98c>] sys_keyctl+0xb4/0xb8 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b if the parent process has no session keyring. If the system is using pam_keyinit then it mostly protected against this as all processes derived from a login will have inherited the session keyring created by pam_keyinit during the log in procedure. To test this, pam_keyinit calls need to be commented out in /etc/pam.d/. Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10KEYS: Fix RCU no-lock warning in keyctl_session_to_parent()David Howells1-0/+3
There's an protected access to the parent process's credentials in the middle of keyctl_session_to_parent(). This results in the following RCU warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/keys/keyctl.c:1291 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by keyctl-session-/2137: #0: (tasklist_lock){.+.+..}, at: [<ffffffff811ae2ec>] keyctl_session_to_parent+0x60/0x236 stack backtrace: Pid: 2137, comm: keyctl-session- Not tainted 2.6.36-rc2-cachefs+ #1 Call Trace: [<ffffffff8105606a>] lockdep_rcu_dereference+0xaa/0xb3 [<ffffffff811ae379>] keyctl_session_to_parent+0xed/0x236 [<ffffffff811af77e>] sys_keyctl+0xb4/0xb6 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b The code should take the RCU read lock to make sure the parents credentials don't go away, even though it's holding a spinlock and has IRQ disabled. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10drm/i915: don't enable self-refresh on IronlakeJesse Barnes2-2/+12
We don't know how to enable it safely, especially as outputs turn on and off. When disabling LP1 we also need to make sure LP2 and 3 are already disabled. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29173 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29082 Reported-by: Chris Lord <chris@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Tested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: stable@kernel.org Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-10xfs: prevent reading uninitialized stack memoryDan Rosenberg1-0/+2
The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12 bytes of uninitialized stack memory, because the fsxattr struct declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero) the 12-byte fsx_pad member before copying it back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-09-10AT91: at91sam9261ek: remove C99 comments but keep informationNicolas Ferre1-4/+2
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-09-10AT91: at91sam9261ek board: remove warnings related to use of SPI or SD/MMCNicolas Ferre1-11/+19
The sd/mmc data structure is not used if SPI is selected. The configuration of PIO on the board prevent from using both interfaces at the same time (board dependent). Remove the warnings at compilation time adding a preprocessor condition. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-09-10AT91: dm9000 initialization updateNicolas Ferre1-1/+2
Add information in dm9000 mac/phy chip initialization: - irq resource details - platform data details Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-09-10block: Range check cpu in blk_cpu_to_groupBrian King1-2/+6
While testing CPU DLPAR, the following problem was discovered. We were DLPAR removing the first CPU, which in this case was logical CPUs 0-3. CPUs 0-2 were already marked offline and we were in the process of offlining CPU 3. After marking the CPU inactive and offline in cpu_disable, but before the cpu was completely idle (cpu_die), we ended up in __make_request on CPU 3. There we looked at the topology map to see which CPU to complete the I/O on and found no CPUs in the cpu_sibling_map. This resulted in the block layer setting the completion cpu to be NR_CPUS, which then caused an oops when we tried to complete the I/O. Fix this by sanity checking the value we return from blk_cpu_to_group to be a valid cpu value. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-09ipheth: remove incorrect devtype to WWANDan Williams1-6/+1
The 'wwan' devtype is meant for devices that require preconfiguration and *every* time setup before the ethernet interface can be used, like cellular modems which require a series of setup commands on serial ports or other mechanisms before the ethernet interface will handle packets. As ipheth only requires one-per-hotplug pairing setup with no preconfiguration (like APN, phone #, etc) and the network interface is usable at any time after that initial setup, remove the incorrect devtype wwan. Signed-off-by: Dan Williams <dcbw@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09MAINTAINERS: Add CAIFJoe Perches1-0/+10
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09tracing: t_start: reset FTRACE_ITER_HASH in case of seek/preadChris Wright1-0/+2
Be sure to avoid entering t_show() with FTRACE_ITER_HASH set without having properly started the iterator to iterate the hash. This case is degenerate and, as discovered by Robert Swiecki, can cause t_hash_show() to misuse a pointer. This causes a NULL ptr deref with possible security implications. Tracked as CVE-2010-3079. Cc: Robert Swiecki <swiecki@google.com> Cc: Eugene Teo <eugene@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-09libata-sff: Reenable Port Multiplier after libata-sff remodeling.Gwendal Grignou3-12/+31
Keep track of the link on the which the current request is in progress. It allows support of links behind port multiplier. Not all libata-sff is PMP compliant. Code for native BMDMA controller does not take in accound PMP. Tested on Marvell 7042 and Sil7526. Signed-off-by: Gwendal Grignou <gwendal@google.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-09-09libata: skip EH autopsy and recovery during suspendTejun Heo3-1/+18
For some mysterious reason, certain hardware reacts badly to usual EH actions while the system is going for suspend. As the devices won't be needed until the system is resumed, ask EH to skip usual autopsy and recovery and proceed directly to suspend. Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Stephan Diestelhorst <stephan.diestelhorst@amd.com> Cc: stable@kernel.org Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-09-09ahci: AHCI and RAID mode SATA patch for Intel Patsburg DeviceIDsSeth Heasley1-0/+3
This patch adds the Intel Patsburg (PCH) SATA AHCI and RAID Controller DeviceIDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-09-09ata_piix: IDE Mode SATA patch for Intel Patsburg DeviceIDsSeth Heasley1-0/+4
This patch adds the Intel Patsburg (PCH) IDE mode SATA Controller DeviceIDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-09-09libata,pata_via: revert ata_wait_idle() removal from ata_sff/via_tf_load()Tejun Heo2-0/+5
Commit 978c0666 (libata: Remove excess delay in the tf_load path) removed ata_wait_idle() from ata_sff_tf_load() and via_tf_load(). This caused obscure detection problems in sata_sil. https://bugzilla.kernel.org/show_bug.cgi?id=16606 The commit was pure performance optimization. Revert it for now. Reported-by: Dieter Plaetinck <dieter@plaetinck.be> Reported-by: Jan Beulich <JBeulich@novell.com> Bisected-by: gianluca <gianluca@sottospazio.it> Cc: stable@kernel.org Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-09-09minix: fix regression in minix_mkdir()Jorge Boncompte [DTI2]1-1/+1
Commit 9eed1fb721c ("minix: replace inode uid,gid,mode init with helper") broke directory creation on minix filesystems. Fix it by passing the needed mode flag to inode init helper. Signed-off-by: Jorge Boncompte [DTI2] <jorge@dti2.net> Cc: Dmitry Monakhov <dmonakhov@openvz.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@kernel.org> [2.6.35.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09mm: page allocator: drain per-cpu lists after direct reclaim allocation failsMel Gorman1-4/+16
When under significant memory pressure, a process enters direct reclaim and immediately afterwards tries to allocate a page. If it fails and no further progress is made, it's possible the system will go OOM. However, on systems with large amounts of memory, it's possible that a significant number of pages are on per-cpu lists and inaccessible to the calling process. This leads to a process entering direct reclaim more often than it should increasing the pressure on the system and compounding the problem. This patch notes that if direct reclaim is making progress but allocations are still failing that the system is already under heavy pressure. In this case, it drains the per-cpu lists and tries the allocation a second time before continuing. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09mm: page allocator: calculate a better estimate of NR_FREE_PAGES when memory is low and kswapd is awakeChristoph Lameter5-3/+72
Ordinarily watermark checks are based on the vmstat NR_FREE_PAGES as it is cheaper than scanning a number of lists. To avoid synchronization overhead, counter deltas are maintained on a per-cpu basis and drained both periodically and when the delta is above a threshold. On large CPU systems, the difference between the estimated and real value of NR_FREE_PAGES can be very high. If NR_FREE_PAGES is much higher than number of real free page in buddy, the VM can allocate pages below min watermark, at worst reducing the real number of pages to zero. Even if the OOM killer kills some victim for freeing memory, it may not free memory if the exit path requires a new page resulting in livelock. This patch introduces a zone_page_state_snapshot() function (courtesy of Christoph) that takes a slightly more accurate view of an arbitrary vmstat counter. It is used to read NR_FREE_PAGES while kswapd is awake to avoid the watermark being accidentally broken. The estimate is not perfect and may result in cache line bounces but is expected to be lighter than the IPI calls necessary to continually drain the per-cpu counters while kswapd is awake. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09mm: page allocator: update free page counters after pages are placed on the free listMel Gorman1-4/+5
When allocating a page, the system uses NR_FREE_PAGES counters to determine if watermarks would remain intact after the allocation was made. This check is made without interrupts disabled or the zone lock held and so is race-prone by nature. Unfortunately, when pages are being freed in batch, the counters are updated before the pages are added on the list. During this window, the counters are misleading as the pages do not exist yet. When under significant pressure on systems with large numbers of CPUs, it's possible for processes to make progress even though they should have been stalled. This is particularly problematic if a number of the processes are using GFP_ATOMIC as the min watermark can be accidentally breached and in extreme cases, the system can livelock. This patch updates the counters after the pages have been added to the list. This makes the allocator more cautious with respect to preserving the watermarks and mitigates livelock possibilities. [akpm@linux-foundation.org: avoid modifying incoming args] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09vmstat: update zone stat threshold when onlining a cpuKAMEZAWA Hiroyuki1-0/+1
refresh_zone_stat_thresholds() calculates parameter based on the number of online cpus. It's called at cpu offlining but needs to be called at onlining, too. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Acked-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09vfs: take O_NONBLOCK out of the O_* uniqueness testJames Bottomley1-3/+7
O_NONBLOCK on parisc has a dual value: #define O_NONBLOCK 000200004 /* HPUX has separate NDELAY & NONBLOCK */ It is caught by the O_* bits uniqueness check and leads to a parisc compile error. The fix would be to take O_NONBLOCK out. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Cc: Jamie Lokier <jamie@shareable.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09swap: discard while swapping only if SWAP_FLAG_DISCARDHugh Dickins2-2/+3
Tests with recent firmware on Intel X25-M 80GB and OCZ Vertex 60GB SSDs show a shift since I last tested in December: in part because of firmware updates, in part because of the necessary move from barriers to awaiting completion at the block layer. While discard at swapon still shows as slightly beneficial on both, discarding 1MB swap cluster when allocating is now disadvanteous: adds 25% overhead on Intel, adds 230% on OCZ (YMMV). Surrender: discard as presently implemented is more hindrance than help for swap; but might prove useful on other devices, or with improvements. So continue to do the discard at swapon, but make discard while swapping conditional on a SWAP_FLAG_DISCARD to sys_swapon() (which has been using only the lower 16 bits of int flags). We can add a --discard or -d to swapon(8), and a "discard" to swap in /etc/fstab: matching the mount option for btrfs, ext4, fat, gfs2, nilfs2. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Nigel Cunningham <nigel@tuxonice.net> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09swap: do not send discards as barriersChristoph Hellwig1-6/+3
The swap code already uses synchronous discards, no need to add I/O barriers. This fixes the worst of the terrible slowdown in swap allocation for hibernation, reported on 2.6.35 by Nigel Cunningham; but does not entirely eliminate that regression. [tj@kernel.org: superflous newlines removed] Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Nigel Cunningham <nigel@tuxonice.net> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09swap: prevent reuse during hibernationHugh Dickins1-4/+20
Move the hibernation check from scan_swap_map() into try_to_free_swap(): to catch not only the common case when hibernation's allocation itself triggers swap reuse, but also the less likely case when concurrent page reclaim (shrink_page_list) might happen to try_to_free_swap from a page. Hibernation already clears __GFP_IO from the gfp_allowed_mask, to stop reclaim from going to swap: check that to prevent swap reuse too. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ondrej Zary <linux@rainbow-software.org> Cc: Andrea Gelmini <andrea.gelmini@gmail.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Nigel Cunningham <nigel@tuxonice.net> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-09swap: revert special hibernation allocationHugh Dickins5-84/+26
Please revert 2.6.36-rc commit d2997b1042ec150616c1963b5e5e919ffd0b0ebf "hibernation: freeze swap at hibernation". It complicated matters by adding a second swap allocation path, just for hibernation; without in any way fixing the issue that it was intended to address - page reclaim after fixing the hibernation image might free swap from a page already imaged as swapcache, letting its swap be reallocated to store a different page of the image: resulting in data corruption if the imaged page were freed as clean then swapped back in. Pages freed to si->swap_map were still in danger of being reallocated by the alternative allocation path. I guess it inadvertently fixed slow SSD swap allocation for hibernation, as reported by Nigel Cunningham: by missing out the discards that occur on the usual swap allocation path; but that was unintentional, and needs a separate fix. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ondrej Zary <linux@rainbow-software.org> Cc: Andrea Gelmini <andrea.gelmini@gmail.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Nigel Cunningham <nigel@tuxonice.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>