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authorLinus Torvalds <torvalds@linux-foundation.org>2014-08-08 15:57:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-08-08 15:57:47 -0700
commit8065be8d032f38da25b54bf077a05a30d9ce9f2a (patch)
tree32a7baf4b40e0240ab4b9dd6f2bbe6129929bb66 /Documentation
parent27d438c56009e5ae632de36fe70985d1aab5e344 (diff)
parentecc265fe9e09e32a3573b2ba26e79b2099eb8bbb (diff)
Merge branch 'akpm' (second patchbomb from Andrew Morton)
Merge more incoming from Andrew Morton: "Two new syscalls: memfd_create in "shm: add memfd_create() syscall" kexec_file_load in "kexec: implementation of new syscall kexec_file_load" And: - Most (all?) of the rest of MM - Lots of the usual misc bits - fs/autofs4 - drivers/rtc - fs/nilfs - procfs - fork.c, exec.c - more in lib/ - rapidio - Janitorial work in filesystems: fs/ufs, fs/reiserfs, fs/adfs, fs/cramfs, fs/romfs, fs/qnx6. - initrd/initramfs work - "file sealing" and the memfd_create() syscall, in tmpfs - add pci_zalloc_consistent, use it in lots of places - MAINTAINERS maintenance - kexec feature work" * emailed patches from Andrew Morton <akpm@linux-foundation.org: (193 commits) MAINTAINERS: update nomadik patterns MAINTAINERS: update usb/gadget patterns MAINTAINERS: update DMA BUFFER SHARING patterns kexec: verify the signature of signed PE bzImage kexec: support kexec/kdump on EFI systems kexec: support for kexec on panic using new system call kexec-bzImage64: support for loading bzImage using 64bit entry kexec: load and relocate purgatory at kernel load time purgatory: core purgatory functionality purgatory/sha256: provide implementation of sha256 in purgaotory context kexec: implementation of new syscall kexec_file_load kexec: new syscall kexec_file_load() declaration kexec: make kexec_segment user buffer pointer a union resource: provide new functions to walk through resources kexec: use common function for kimage_normal_alloc() and kimage_crash_alloc() kexec: move segment verification code in a separate function kexec: rename unusebale_pages to unusable_pages kernel: build bin2c based on config option CONFIG_BUILD_BIN2C bin2c: move bin2c in scripts/basic shm: wait for pins to be released when sealing ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-fs-nilfs2269
-rw-r--r--Documentation/cgroups/memcg_test.txt160
-rw-r--r--Documentation/devicetree/bindings/i2c/trivial-devices.txt1
-rw-r--r--Documentation/oops-tracing.txt2
-rw-r--r--Documentation/rapidio/tsi721.txt19
-rw-r--r--Documentation/sysctl/kernel.txt1
6 files changed, 300 insertions, 152 deletions
diff --git a/Documentation/ABI/testing/sysfs-fs-nilfs2 b/Documentation/ABI/testing/sysfs-fs-nilfs2
new file mode 100644
index 00000000000..304ba84a973
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-fs-nilfs2
@@ -0,0 +1,269 @@
+
+What: /sys/fs/nilfs2/features/revision
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show current revision of NILFS file system driver.
+ This value informs about file system revision that
+ driver is ready to support.
+
+What: /sys/fs/nilfs2/features/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/features group.
+
+What: /sys/fs/nilfs2/<device>/revision
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show NILFS file system revision on volume.
+ This value informs about metadata structures'
+ revision on mounted volume.
+
+What: /sys/fs/nilfs2/<device>/blocksize
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show volume's block size in bytes.
+
+What: /sys/fs/nilfs2/<device>/device_size
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show volume size in bytes.
+
+What: /sys/fs/nilfs2/<device>/free_blocks
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show count of free blocks on volume.
+
+What: /sys/fs/nilfs2/<device>/uuid
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show volume's UUID (Universally Unique Identifier).
+
+What: /sys/fs/nilfs2/<device>/volume_name
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show volume's label.
+
+What: /sys/fs/nilfs2/<device>/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device> group.
+
+What: /sys/fs/nilfs2/<device>/superblock/sb_write_time
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show last write time of super block in human-readable
+ format.
+
+What: /sys/fs/nilfs2/<device>/superblock/sb_write_time_secs
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show last write time of super block in seconds.
+
+What: /sys/fs/nilfs2/<device>/superblock/sb_write_count
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show current write count of super block.
+
+What: /sys/fs/nilfs2/<device>/superblock/sb_update_frequency
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show/Set interval of periodical update of superblock
+ (in seconds).
+
+What: /sys/fs/nilfs2/<device>/superblock/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device>/superblock
+ group.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_pseg_block
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show start block number of the latest segment.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_seg_sequence
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show sequence value of the latest segment.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_seg_checkpoint
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show checkpoint number of the latest segment.
+
+What: /sys/fs/nilfs2/<device>/segctor/current_seg_sequence
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show segment sequence counter.
+
+What: /sys/fs/nilfs2/<device>/segctor/current_last_full_seg
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show index number of the latest full segment.
+
+What: /sys/fs/nilfs2/<device>/segctor/next_full_seg
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show index number of the full segment index
+ to be used next.
+
+What: /sys/fs/nilfs2/<device>/segctor/next_pseg_offset
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show offset of next partial segment in the current
+ full segment.
+
+What: /sys/fs/nilfs2/<device>/segctor/next_checkpoint
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show next checkpoint number.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_seg_write_time
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show write time of the last segment in
+ human-readable format.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_seg_write_time_secs
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show write time of the last segment in seconds.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_nongc_write_time
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show write time of the last segment not for cleaner
+ operation in human-readable format.
+
+What: /sys/fs/nilfs2/<device>/segctor/last_nongc_write_time_secs
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show write time of the last segment not for cleaner
+ operation in seconds.
+
+What: /sys/fs/nilfs2/<device>/segctor/dirty_data_blocks_count
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of dirty data blocks.
+
+What: /sys/fs/nilfs2/<device>/segctor/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device>/segctor
+ group.
+
+What: /sys/fs/nilfs2/<device>/segments/segments_number
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of segments on a volume.
+
+What: /sys/fs/nilfs2/<device>/segments/blocks_per_segment
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of blocks in segment.
+
+What: /sys/fs/nilfs2/<device>/segments/clean_segments
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show count of clean segments.
+
+What: /sys/fs/nilfs2/<device>/segments/dirty_segments
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show count of dirty segments.
+
+What: /sys/fs/nilfs2/<device>/segments/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device>/segments
+ group.
+
+What: /sys/fs/nilfs2/<device>/checkpoints/checkpoints_number
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of checkpoints on volume.
+
+What: /sys/fs/nilfs2/<device>/checkpoints/snapshots_number
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of snapshots on volume.
+
+What: /sys/fs/nilfs2/<device>/checkpoints/last_seg_checkpoint
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show checkpoint number of the latest segment.
+
+What: /sys/fs/nilfs2/<device>/checkpoints/next_checkpoint
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show next checkpoint number.
+
+What: /sys/fs/nilfs2/<device>/checkpoints/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device>/checkpoints
+ group.
+
+What: /sys/fs/nilfs2/<device>/mounted_snapshots/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe content of /sys/fs/nilfs2/<device>/mounted_snapshots
+ group.
+
+What: /sys/fs/nilfs2/<device>/mounted_snapshots/<id>/inodes_count
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of inodes for snapshot.
+
+What: /sys/fs/nilfs2/<device>/mounted_snapshots/<id>/blocks_count
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Show number of blocks for snapshot.
+
+What: /sys/fs/nilfs2/<device>/mounted_snapshots/<id>/README
+Date: April 2014
+Contact: "Vyacheslav Dubeyko" <slava@dubeyko.com>
+Description:
+ Describe attributes of /sys/fs/nilfs2/<device>/mounted_snapshots/<id>
+ group.
diff --git a/Documentation/cgroups/memcg_test.txt b/Documentation/cgroups/memcg_test.txt
index 80ac454704b..8870b021215 100644
--- a/Documentation/cgroups/memcg_test.txt
+++ b/Documentation/cgroups/memcg_test.txt
@@ -24,64 +24,27 @@ Please note that implementation details can be changed.
a page/swp_entry may be charged (usage += PAGE_SIZE) at
- mem_cgroup_charge_anon()
- Called at new page fault and Copy-On-Write.
-
- mem_cgroup_try_charge_swapin()
- Called at do_swap_page() (page fault on swap entry) and swapoff.
- Followed by charge-commit-cancel protocol. (With swap accounting)
- At commit, a charge recorded in swap_cgroup is removed.
-
- mem_cgroup_charge_file()
- Called at add_to_page_cache()
-
- mem_cgroup_cache_charge_swapin()
- Called at shmem's swapin.
-
- mem_cgroup_prepare_migration()
- Called before migration. "extra" charge is done and followed by
- charge-commit-cancel protocol.
- At commit, charge against oldpage or newpage will be committed.
+ mem_cgroup_try_charge()
2. Uncharge
a page/swp_entry may be uncharged (usage -= PAGE_SIZE) by
- mem_cgroup_uncharge_page()
- Called when an anonymous page is fully unmapped. I.e., mapcount goes
- to 0. If the page is SwapCache, uncharge is delayed until
- mem_cgroup_uncharge_swapcache().
-
- mem_cgroup_uncharge_cache_page()
- Called when a page-cache is deleted from radix-tree. If the page is
- SwapCache, uncharge is delayed until mem_cgroup_uncharge_swapcache().
-
- mem_cgroup_uncharge_swapcache()
- Called when SwapCache is removed from radix-tree. The charge itself
- is moved to swap_cgroup. (If mem+swap controller is disabled, no
- charge to swap occurs.)
+ mem_cgroup_uncharge()
+ Called when a page's refcount goes down to 0.
mem_cgroup_uncharge_swap()
Called when swp_entry's refcnt goes down to 0. A charge against swap
disappears.
- mem_cgroup_end_migration(old, new)
- At success of migration old is uncharged (if necessary), a charge
- to new page is committed. At failure, charge to old page is committed.
-
3. charge-commit-cancel
- In some case, we can't know this "charge" is valid or not at charging
- (because of races).
- To handle such case, there are charge-commit-cancel functions.
- mem_cgroup_try_charge_XXX
- mem_cgroup_commit_charge_XXX
- mem_cgroup_cancel_charge_XXX
- these are used in swap-in and migration.
+ Memcg pages are charged in two steps:
+ mem_cgroup_try_charge()
+ mem_cgroup_commit_charge() or mem_cgroup_cancel_charge()
At try_charge(), there are no flags to say "this page is charged".
at this point, usage += PAGE_SIZE.
- At commit(), the function checks the page should be charged or not
- and set flags or avoid charging.(usage -= PAGE_SIZE)
+ At commit(), the page is associated with the memcg.
At cancel(), simply usage -= PAGE_SIZE.
@@ -91,18 +54,6 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
Anonymous page is newly allocated at
- page fault into MAP_ANONYMOUS mapping.
- Copy-On-Write.
- It is charged right after it's allocated before doing any page table
- related operations. Of course, it's uncharged when another page is used
- for the fault address.
-
- At freeing anonymous page (by exit() or munmap()), zap_pte() is called
- and pages for ptes are freed one by one.(see mm/memory.c). Uncharges
- are done at page_remove_rmap() when page_mapcount() goes down to 0.
-
- Another page freeing is by page-reclaim (vmscan.c) and anonymous
- pages are swapped out. In this case, the page is marked as
- PageSwapCache(). uncharge() routine doesn't uncharge the page marked
- as SwapCache(). It's delayed until __delete_from_swap_cache().
4.1 Swap-in.
At swap-in, the page is taken from swap-cache. There are 2 cases.
@@ -111,41 +62,6 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
(b) If the SwapCache has been mapped by processes, it has been
charged already.
- This swap-in is one of the most complicated work. In do_swap_page(),
- following events occur when pte is unchanged.
-
- (1) the page (SwapCache) is looked up.
- (2) lock_page()
- (3) try_charge_swapin()
- (4) reuse_swap_page() (may call delete_swap_cache())
- (5) commit_charge_swapin()
- (6) swap_free().
-
- Considering following situation for example.
-
- (A) The page has not been charged before (2) and reuse_swap_page()
- doesn't call delete_from_swap_cache().
- (B) The page has not been charged before (2) and reuse_swap_page()
- calls delete_from_swap_cache().
- (C) The page has been charged before (2) and reuse_swap_page() doesn't
- call delete_from_swap_cache().
- (D) The page has been charged before (2) and reuse_swap_page() calls
- delete_from_swap_cache().
-
- memory.usage/memsw.usage changes to this page/swp_entry will be
- Case (A) (B) (C) (D)
- Event
- Before (2) 0/ 1 0/ 1 1/ 1 1/ 1
- ===========================================
- (3) +1/+1 +1/+1 +1/+1 +1/+1
- (4) - 0/ 0 - -1/ 0
- (5) 0/-1 0/ 0 -1/-1 0/ 0
- (6) - 0/-1 - 0/-1
- ===========================================
- Result 1/ 1 1/ 1 1/ 1 1/ 1
-
- In any cases, charges to this page should be 1/ 1.
-
4.2 Swap-out.
At swap-out, typical state transition is below.
@@ -158,28 +74,20 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
swp_entry's refcnt -= 1.
- At (b), the page is marked as SwapCache and not uncharged.
- At (d), the page is removed from SwapCache and a charge in page_cgroup
- is moved to swap_cgroup.
-
Finally, at task exit,
(e) zap_pte() is called and swp_entry's refcnt -=1 -> 0.
- Here, a charge in swap_cgroup disappears.
5. Page Cache
Page Cache is charged at
- add_to_page_cache_locked().
- uncharged at
- - __remove_from_page_cache().
-
The logic is very clear. (About migration, see below)
Note: __remove_from_page_cache() is called by remove_from_page_cache()
and __remove_mapping().
6. Shmem(tmpfs) Page Cache
- Memcg's charge/uncharge have special handlers of shmem. The best way
- to understand shmem's page state transition is to read mm/shmem.c.
+ The best way to understand shmem's page state transition is to read
+ mm/shmem.c.
But brief explanation of the behavior of memcg around shmem will be
helpful to understand the logic.
@@ -192,56 +100,10 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
It's charged when...
- A new page is added to shmem's radix-tree.
- A swp page is read. (move a charge from swap_cgroup to page_cgroup)
- It's uncharged when
- - A page is removed from radix-tree and not SwapCache.
- - When SwapCache is removed, a charge is moved to swap_cgroup.
- - When swp_entry's refcnt goes down to 0, a charge in swap_cgroup
- disappears.
7. Page Migration
- One of the most complicated functions is page-migration-handler.
- Memcg has 2 routines. Assume that we are migrating a page's contents
- from OLDPAGE to NEWPAGE.
-
- Usual migration logic is..
- (a) remove the page from LRU.
- (b) allocate NEWPAGE (migration target)
- (c) lock by lock_page().
- (d) unmap all mappings.
- (e-1) If necessary, replace entry in radix-tree.
- (e-2) move contents of a page.
- (f) map all mappings again.
- (g) pushback the page to LRU.
- (-) OLDPAGE will be freed.
-
- Before (g), memcg should complete all necessary charge/uncharge to
- NEWPAGE/OLDPAGE.
-
- The point is....
- - If OLDPAGE is anonymous, all charges will be dropped at (d) because
- try_to_unmap() drops all mapcount and the page will not be
- SwapCache.
-
- - If OLDPAGE is SwapCache, charges will be kept at (g) because
- __delete_from_swap_cache() isn't called at (e-1)
-
- - If OLDPAGE is page-cache, charges will be kept at (g) because
- remove_from_swap_cache() isn't called at (e-1)
-
- memcg provides following hooks.
-
- - mem_cgroup_prepare_migration(OLDPAGE)
- Called after (b) to account a charge (usage += PAGE_SIZE) against
- memcg which OLDPAGE belongs to.
-
- - mem_cgroup_end_migration(OLDPAGE, NEWPAGE)
- Called after (f) before (g).
- If OLDPAGE is used, commit OLDPAGE again. If OLDPAGE is already
- charged, a charge by prepare_migration() is automatically canceled.
- If NEWPAGE is used, commit NEWPAGE and uncharge OLDPAGE.
-
- But zap_pte() (by exit or munmap) can be called while migration,
- we have to check if OLDPAGE/NEWPAGE is a valid page after commit().
+
+ mem_cgroup_migrate()
8. LRU
Each memcg has its own private LRU. Now, its handling is under global
diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index 37803eb5521..6af570ec53b 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -70,6 +70,7 @@ nuvoton,npct501 i2c trusted platform module (TPM)
nxp,pca9556 Octal SMBus and I2C registered interface
nxp,pca9557 8-bit I2C-bus and SMBus I/O port with reset
nxp,pcf8563 Real-time clock/calendar
+nxp,pcf85063 Tiny Real-Time Clock
ovti,ov5642 OV5642: Color CMOS QSXGA (5-megapixel) Image Sensor with OmniBSI and Embedded TrueFocus
pericom,pt7c4338 Real-time Clock Module
plx,pex8648 48-Lane, 12-Port PCI Express Gen 2 (5.0 GT/s) Switch
diff --git a/Documentation/oops-tracing.txt b/Documentation/oops-tracing.txt
index e3155995ddd..beefb9f8290 100644
--- a/Documentation/oops-tracing.txt
+++ b/Documentation/oops-tracing.txt
@@ -268,6 +268,8 @@ characters, each representing a particular tainted value.
14: 'E' if an unsigned module has been loaded in a kernel supporting
module signature.
+ 15: 'L' if a soft lockup has previously occurred on the system.
+
The primary reason for the 'Tainted: ' string is to tell kernel
debuggers if this is a clean kernel or if anything unusual has
occurred. Tainting is permanent: even if an offending module is
diff --git a/Documentation/rapidio/tsi721.txt b/Documentation/rapidio/tsi721.txt
index 335f3c6087d..626052f403b 100644
--- a/Documentation/rapidio/tsi721.txt
+++ b/Documentation/rapidio/tsi721.txt
@@ -20,13 +20,26 @@ II. Known problems
None.
-III. To do
+III. DMA Engine Support
- Add DMA data transfers (non-messaging).
- Add inbound region (SRIO-to-PCIe) mapping.
+Tsi721 mport driver supports DMA data transfers between local system memory and
+remote RapidIO devices. This functionality is implemented according to SLAVE
+mode API defined by common Linux kernel DMA Engine framework.
+
+Depending on system requirements RapidIO DMA operations can be included/excluded
+by setting CONFIG_RAPIDIO_DMA_ENGINE option. Tsi721 miniport driver uses seven
+out of eight available BDMA channels to support DMA data transfers.
+One BDMA channel is reserved for generation of maintenance read/write requests.
+
+If Tsi721 mport driver have been built with RAPIDIO_DMA_ENGINE support included,
+this driver will accept DMA-specific module parameter:
+ "dma_desc_per_channel" - defines number of hardware buffer descriptors used by
+ each BDMA channel of Tsi721 (by default - 128).
IV. Version History
+ 1.1.0 - DMA operations re-worked to support data scatter/gather lists larger
+ than hardware buffer descriptors ring.
1.0.0 - Initial driver release.
V. License
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index c14374e7177..f79eb966637 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -826,6 +826,7 @@ can be ORed together:
4096 - An out-of-tree module has been loaded.
8192 - An unsigned module has been loaded in a kernel supporting module
signature.
+16384 - A soft lockup has previously occurred on the system.
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