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-rw-r--r--Documentation/ABI/testing/sysfs-gpio26
-rw-r--r--Documentation/DMA-mapping.txt2
-rw-r--r--Documentation/HOWTO3
-rw-r--r--Documentation/SubmitChecklist2
-rw-r--r--Documentation/cpusets.txt18
-rw-r--r--Documentation/feature-removal-schedule.txt8
-rw-r--r--Documentation/filesystems/Locking15
-rw-r--r--Documentation/filesystems/proc.txt2
-rw-r--r--Documentation/ioctl/cdrom.txt4
-rw-r--r--Documentation/sysctl/kernel.txt7
-rw-r--r--Documentation/usb/anchors.txt12
11 files changed, 73 insertions, 26 deletions
diff --git a/Documentation/ABI/testing/sysfs-gpio b/Documentation/ABI/testing/sysfs-gpio
new file mode 100644
index 000000000000..8aab8092ad35
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-gpio
@@ -0,0 +1,26 @@
+What: /sys/class/gpio/
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Brownell <dbrownell@users.sourceforge.net>
+Description:
+
+ As a Kconfig option, individual GPIO signals may be accessed from
+ userspace. GPIOs are only made available to userspace by an explicit
+ "export" operation. If a given GPIO is not claimed for use by
+ kernel code, it may be exported by userspace (and unexported later).
+ Kernel code may export it for complete or partial access.
+
+ GPIOs are identified as they are inside the kernel, using integers in
+ the range 0..INT_MAX. See Documentation/gpio.txt for more information.
+
+ /sys/class/gpio
+ /export ... asks the kernel to export a GPIO to userspace
+ /unexport ... to return a GPIO to the kernel
+ /gpioN ... for each exported GPIO #N
+ /value ... always readable, writes fail for input GPIOs
+ /direction ... r/w as: in, out (default low); write: high, low
+ /gpiochipN ... for each gpiochip; #N is its first GPIO
+ /base ... (r/o) same as N
+ /label ... (r/o) descriptive, not necessarily unique
+ /ngpio ... (r/o) number of GPIOs; numbered N to N + (ngpio - 1)
+
diff --git a/Documentation/DMA-mapping.txt b/Documentation/DMA-mapping.txt
index b463ecd0c7ce..c74fec8c2351 100644
--- a/Documentation/DMA-mapping.txt
+++ b/Documentation/DMA-mapping.txt
@@ -740,7 +740,7 @@ failure can be determined by:
dma_addr_t dma_handle;
dma_handle = pci_map_single(pdev, addr, size, direction);
- if (pci_dma_mapping_error(dma_handle)) {
+ if (pci_dma_mapping_error(pdev, dma_handle)) {
/*
* reduce current DMA mapping usage,
* delay and try again later or
diff --git a/Documentation/HOWTO b/Documentation/HOWTO
index c2371c5a98f9..48a3955f05fc 100644
--- a/Documentation/HOWTO
+++ b/Documentation/HOWTO
@@ -77,7 +77,8 @@ documentation files are also added which explain how to use the feature.
When a kernel change causes the interface that the kernel exposes to
userspace to change, it is recommended that you send the information or
a patch to the manual pages explaining the change to the manual pages
-maintainer at mtk.manpages@gmail.com.
+maintainer at mtk.manpages@gmail.com, and CC the list
+linux-api@vger.kernel.org.
Here is a list of files that are in the kernel source tree that are
required reading:
diff --git a/Documentation/SubmitChecklist b/Documentation/SubmitChecklist
index da10e0714241..21f0795af20f 100644
--- a/Documentation/SubmitChecklist
+++ b/Documentation/SubmitChecklist
@@ -67,6 +67,8 @@ kernel patches.
19: All new userspace interfaces are documented in Documentation/ABI/.
See Documentation/ABI/README for more information.
+ Patches that change userspace interfaces should be CCed to
+ linux-api@vger.kernel.org.
20: Check that it all passes `make headers_check'.
diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt
index 1f5a924d1e56..47e568a9370a 100644
--- a/Documentation/cpusets.txt
+++ b/Documentation/cpusets.txt
@@ -635,14 +635,16 @@ prior 'mems' setting, will not be moved.
There is an exception to the above. If hotplug functionality is used
to remove all the CPUs that are currently assigned to a cpuset,
-then the kernel will automatically update the cpus_allowed of all
-tasks attached to CPUs in that cpuset to allow all CPUs. When memory
-hotplug functionality for removing Memory Nodes is available, a
-similar exception is expected to apply there as well. In general,
-the kernel prefers to violate cpuset placement, over starving a task
-that has had all its allowed CPUs or Memory Nodes taken offline. User
-code should reconfigure cpusets to only refer to online CPUs and Memory
-Nodes when using hotplug to add or remove such resources.
+then all the tasks in that cpuset will be moved to the nearest ancestor
+with non-empty cpus. But the moving of some (or all) tasks might fail if
+cpuset is bound with another cgroup subsystem which has some restrictions
+on task attaching. In this failing case, those tasks will stay
+in the original cpuset, and the kernel will automatically update
+their cpus_allowed to allow all online CPUs. When memory hotplug
+functionality for removing Memory Nodes is available, a similar exception
+is expected to apply there as well. In general, the kernel prefers to
+violate cpuset placement, over starving a task that has had all
+its allowed CPUs or Memory Nodes taken offline.
There is a second exception to the above. GFP_ATOMIC requests are
kernel internal allocations that must be satisfied, immediately.
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index eb1a47b97427..83c88cae1eda 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -322,3 +322,11 @@ Why: Accounting can now be enabled/disabled without kernel recompilation.
controlled by a kernel/module/sysfs/sysctl parameter.
Who: Krzysztof Piotr Oledzki <ole@ans.pl>
+---------------------------
+
+What: ide-scsi (BLK_DEV_IDESCSI)
+When: 2.6.29
+Why: The 2.6 kernel supports direct writing to ide CD drives, which
+ eliminates the need for ide-scsi. The new method is more
+ efficient in every way.
+Who: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 680fb566b928..8362860e21a7 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -144,8 +144,8 @@ prototypes:
void (*kill_sb) (struct super_block *);
locking rules:
may block BKL
-get_sb yes yes
-kill_sb yes yes
+get_sb yes no
+kill_sb yes no
->get_sb() returns error or 0 with locked superblock attached to the vfsmount
(exclusive on ->s_umount).
@@ -409,12 +409,12 @@ ioctl: yes (see below)
unlocked_ioctl: no (see below)
compat_ioctl: no
mmap: no
-open: maybe (see below)
+open: no
flush: no
release: no
fsync: no (see below)
aio_fsync: no
-fasync: yes (see below)
+fasync: no
lock: yes
readv: no
writev: no
@@ -431,13 +431,6 @@ For many filesystems, it is probably safe to acquire the inode
semaphore. Note some filesystems (i.e. remote ones) provide no
protection for i_size so you will need to use the BKL.
-->open() locking is in-transit: big lock partially moved into the methods.
-The only exception is ->open() in the instances of file_operations that never
-end up in ->i_fop/->proc_fops, i.e. ones that belong to character devices
-(chrdev_open() takes lock before replacing ->f_op and calling the secondary
-method. As soon as we fix the handling of module reference counters all
-instances of ->open() will be called without the BKL.
-
Note: ext2_release() was *the* source of contention on fs-intensive
loads and dropping BKL on ->release() helps to get rid of that (we still
grab BKL for cases when we close a file that had been opened r/w, but that
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 394eb2cc1c39..f566ad9bcb7b 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -2413,6 +2413,8 @@ The following 4 memory types are supported:
- (bit 1) anonymous shared memory
- (bit 2) file-backed private memory
- (bit 3) file-backed shared memory
+ - (bit 4) ELF header pages in file-backed private memory areas (it is
+ effective only if the bit 2 is cleared)
Note that MMIO pages such as frame buffer are never dumped and vDSO pages
are always dumped regardless of the bitmask status.
diff --git a/Documentation/ioctl/cdrom.txt b/Documentation/ioctl/cdrom.txt
index 62d4af44ec4a..59df81c8da2b 100644
--- a/Documentation/ioctl/cdrom.txt
+++ b/Documentation/ioctl/cdrom.txt
@@ -271,14 +271,14 @@ CDROMCLOSETRAY pendant of CDROMEJECT
usage:
- ioctl(fd, CDROMEJECT, 0);
+ ioctl(fd, CDROMCLOSETRAY, 0);
inputs: none
outputs: none
error returns:
- ENOSYS cd drive not capable of ejecting
+ ENOSYS cd drive not capable of closing the tray
EBUSY other processes are accessing drive, or door is locked
notes:
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 276a7e637822..e1ff0d920a5c 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -351,9 +351,10 @@ kernel. This value defaults to SHMMAX.
softlockup_thresh:
-This value can be used to lower the softlockup tolerance
-threshold. The default threshold is 10s. If a cpu is locked up
-for 10s, the kernel complains. Valid values are 1-60s.
+This value can be used to lower the softlockup tolerance threshold. The
+default threshold is 60 seconds. If a cpu is locked up for 60 seconds,
+the kernel complains. Valid values are 1-60 seconds. Setting this
+tunable to zero will disable the softlockup detection altogether.
==============================================================
diff --git a/Documentation/usb/anchors.txt b/Documentation/usb/anchors.txt
index 7304bcf5a306..5e6b64c20d25 100644
--- a/Documentation/usb/anchors.txt
+++ b/Documentation/usb/anchors.txt
@@ -42,9 +42,21 @@ This function kills all URBs associated with an anchor. The URBs
are called in the reverse temporal order they were submitted.
This way no data can be reordered.
+usb_unlink_anchored_urbs()
+--------------------------
+
+This function unlinks all URBs associated with an anchor. The URBs
+are processed in the reverse temporal order they were submitted.
+This is similar to usb_kill_anchored_urbs(), but it will not sleep.
+Therefore no guarantee is made that the URBs have been unlinked when
+the call returns. They may be unlinked later but will be unlinked in
+finite time.
+
usb_wait_anchor_empty_timeout()
-------------------------------
This function waits for all URBs associated with an anchor to finish
or a timeout, whichever comes first. Its return value will tell you
whether the timeout was reached.
+
+