The standard 32-bit addressing PCI device would do something like
this:
- if (pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
+ if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
printk(KERN_WARNING
"mydev: No suitable DMA available.\n");
goto ignore_this_device;
int using_dac;
- if (!pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
+ if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(64))) {
using_dac = 1;
- } else if (!pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
+ } else if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
using_dac = 0;
} else {
printk(KERN_WARNING
int using_dac, consistent_using_dac;
- if (!pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
+ if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(64))) {
using_dac = 1;
consistent_using_dac = 1;
- pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
- } else if (!pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
+ pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+ } else if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
using_dac = 0;
consistent_using_dac = 0;
- pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
+ pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
} else {
printk(KERN_WARNING
"mydev: No suitable DMA available.\n");
Finally, if your device can only drive the low 24-bits of
address during PCI bus mastering you might do something like:
- if (pci_set_dma_mask(pdev, DMA_24BIT_MASK)) {
+ if (pci_set_dma_mask(pdev, DMA_BIT_MASK(24))) {
printk(KERN_WARNING
"mydev: 24-bit DMA addressing not available.\n");
goto ignore_this_device;
Here is pseudo-code showing how this might be done:
- #define PLAYBACK_ADDRESS_BITS DMA_32BIT_MASK
+ #define PLAYBACK_ADDRESS_BITS DMA_BIT_MASK(32)
#define RECORD_ADDRESS_BITS 0x00ffffff
struct my_sound_card *card;
!Eblock/blk-tag.c
!Iblock/blk-tag.c
!Eblock/blk-integrity.c
-!Iblock/blktrace.c
+!Ikernel/trace/blktrace.c
!Iblock/genhd.c
!Eblock/genhd.c
</chapter>
if (err < 0)
return err;
/* check PCI availability (28bit DMA) */
- if (pci_set_dma_mask(pci, DMA_28BIT_MASK) < 0 ||
- pci_set_consistent_dma_mask(pci, DMA_28BIT_MASK) < 0) {
+ if (pci_set_dma_mask(pci, DMA_BIT_MASK(28)) < 0 ||
+ pci_set_consistent_dma_mask(pci, DMA_BIT_MASK(28)) < 0) {
printk(KERN_ERR "error to set 28bit mask DMA\n");
pci_disable_device(pci);
return -ENXIO;
err = pci_enable_device(pci);
if (err < 0)
return err;
- if (pci_set_dma_mask(pci, DMA_28BIT_MASK) < 0 ||
- pci_set_consistent_dma_mask(pci, DMA_28BIT_MASK) < 0) {
+ if (pci_set_dma_mask(pci, DMA_BIT_MASK(28)) < 0 ||
+ pci_set_consistent_dma_mask(pci, DMA_BIT_MASK(28)) < 0) {
printk(KERN_ERR "error to set 28bit mask DMA\n");
pci_disable_device(pci);
return -ENXIO;
- info on using Compaq's SMART2 Intelligent Disk Array Controllers.
floppy.txt
- notes and driver options for the floppy disk driver.
+mflash.txt
+ - info on mGine m(g)flash driver for linux.
nbd.txt
- info on a TCP implementation of a network block device.
paride.txt
--- /dev/null
+This document describes m[g]flash support in linux.
+
+Contents
+ 1. Overview
+ 2. Reserved area configuration
+ 3. Example of mflash platform driver registration
+
+1. Overview
+
+Mflash and gflash are embedded flash drive. The only difference is mflash is
+MCP(Multi Chip Package) device. These two device operate exactly same way.
+So the rest mflash repersents mflash and gflash altogether.
+
+Internally, mflash has nand flash and other hardware logics and supports
+2 different operation (ATA, IO) modes. ATA mode doesn't need any new
+driver and currently works well under standard IDE subsystem. Actually it's
+one chip SSD. IO mode is ATA-like custom mode for the host that doesn't have
+IDE interface.
+
+Followings are brief descriptions about IO mode.
+A. IO mode based on ATA protocol and uses some custom command. (read confirm,
+write confirm)
+B. IO mode uses SRAM bus interface.
+C. IO mode supports 4kB boot area, so host can boot from mflash.
+
+2. Reserved area configuration
+If host boot from mflash, usually needs raw area for boot loader image. All of
+the mflash's block device operation will be taken this value as start offset.
+Note that boot loader's size of reserved area and kernel configuration value
+must be same.
+
+3. Example of mflash platform driver registration
+Working mflash is very straight forward. Adding platform device stuff to board
+configuration file is all. Here is some pseudo example.
+
+static struct mg_drv_data mflash_drv_data = {
+ /* If you want to polling driver set to 1 */
+ .use_polling = 0,
+ /* device attribution */
+ .dev_attr = MG_BOOT_DEV
+};
+
+static struct resource mg_mflash_rsc[] = {
+ /* Base address of mflash */
+ [0] = {
+ .start = 0x08000000,
+ .end = 0x08000000 + SZ_64K - 1,
+ .flags = IORESOURCE_MEM
+ },
+ /* mflash interrupt pin */
+ [1] = {
+ .start = IRQ_GPIO(84),
+ .end = IRQ_GPIO(84),
+ .flags = IORESOURCE_IRQ
+ },
+ /* mflash reset pin */
+ [2] = {
+ .start = 43,
+ .end = 43,
+ .name = MG_RST_PIN,
+ .flags = IORESOURCE_IO
+ },
+ /* mflash reset-out pin
+ * If you use mflash as storage device (i.e. other than MG_BOOT_DEV),
+ * should assign this */
+ [3] = {
+ .start = 51,
+ .end = 51,
+ .name = MG_RSTOUT_PIN,
+ .flags = IORESOURCE_IO
+ }
+};
+
+static struct platform_device mflash_dev = {
+ .name = MG_DEV_NAME,
+ .id = -1,
+ .dev = {
+ .platform_data = &mflash_drv_data,
+ },
+ .num_resources = ARRAY_SIZE(mg_mflash_rsc),
+ .resource = mg_mflash_rsc
+};
+
+platform_device_register(&mflash_dev);
Maintained by Alan Cox <device@lanana.org>
- Last revised: 29 November 2006
+ Last revised: 6th April 2009
This list is the Linux Device List, the official registry of allocated
device numbers and /dev directory nodes for the Linux operating
206 = /dev/ttySC1 SC26xx serial port 1
207 = /dev/ttySC2 SC26xx serial port 2
208 = /dev/ttySC3 SC26xx serial port 3
+ 209 = /dev/ttyMAX0 MAX3100 serial port 0
+ 210 = /dev/ttyMAX1 MAX3100 serial port 1
+ 211 = /dev/ttyMAX2 MAX3100 serial port 2
+ 212 = /dev/ttyMAX3 MAX3100 serial port 3
205 char Low-density serial ports (alternate device)
0 = /dev/culu0 Callout device for ttyLU0
ypan Enable display panning using the VESA protected mode
interface. The visible screen is just a window of the
video memory, console scrolling is done by changing the
- start of the window. Available on x86 only.
+ start of the window. This option is available on x86
+ only and is the default option on that architecture.
ywrap Same as ypan, but assumes your gfx board can wrap-around
the video memory (i.e. starts reading from top if it
Available on x86 only.
redraw Scroll by redrawing the affected part of the screen, this
- is the safe (and slow) default.
+ is the default on non-x86.
(If you're using uvesafb as a module, the above three options are
used a parameter of the scroll option, e.g. scroll=ypan.)
--
Michal Januszewski <spock@gentoo.org>
- Last updated: 2007-06-16
+ Last updated: 2009-03-30
Documentation of the uvesafb options is loosely based on vesafb.txt.
---------------------------
-What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client()
+What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client(),
+ i2c_adapter->client_register(), i2c_adapter->client_unregister
When: 2.6.30
Check: i2c_attach_client i2c_detach_client
Why: Deprecated by the new (standard) device driver binding model. Use
- info on Novell Netware(tm) filesystem using NCP protocol.
nfsroot.txt
- short guide on setting up a diskless box with NFS root filesystem.
+nilfs2.txt
+ - info and mount options for the NILFS2 filesystem.
ntfs.txt
- info and mount options for the NTFS filesystem (Windows NT).
ocfs2.txt
--- /dev/null
+
+Kernel NFS Server Statistics
+============================
+
+This document describes the format and semantics of the statistics
+which the kernel NFS server makes available to userspace. These
+statistics are available in several text form pseudo files, each of
+which is described separately below.
+
+In most cases you don't need to know these formats, as the nfsstat(8)
+program from the nfs-utils distribution provides a helpful command-line
+interface for extracting and printing them.
+
+All the files described here are formatted as a sequence of text lines,
+separated by newline '\n' characters. Lines beginning with a hash
+'#' character are comments intended for humans and should be ignored
+by parsing routines. All other lines contain a sequence of fields
+separated by whitespace.
+
+/proc/fs/nfsd/pool_stats
+------------------------
+
+This file is available in kernels from 2.6.30 onwards, if the
+/proc/fs/nfsd filesystem is mounted (it almost always should be).
+
+The first line is a comment which describes the fields present in
+all the other lines. The other lines present the following data as
+a sequence of unsigned decimal numeric fields. One line is shown
+for each NFS thread pool.
+
+All counters are 64 bits wide and wrap naturally. There is no way
+to zero these counters, instead applications should do their own
+rate conversion.
+
+pool
+ The id number of the NFS thread pool to which this line applies.
+ This number does not change.
+
+ Thread pool ids are a contiguous set of small integers starting
+ at zero. The maximum value depends on the thread pool mode, but
+ currently cannot be larger than the number of CPUs in the system.
+ Note that in the default case there will be a single thread pool
+ which contains all the nfsd threads and all the CPUs in the system,
+ and thus this file will have a single line with a pool id of "0".
+
+packets-arrived
+ Counts how many NFS packets have arrived. More precisely, this
+ is the number of times that the network stack has notified the
+ sunrpc server layer that new data may be available on a transport
+ (e.g. an NFS or UDP socket or an NFS/RDMA endpoint).
+
+ Depending on the NFS workload patterns and various network stack
+ effects (such as Large Receive Offload) which can combine packets
+ on the wire, this may be either more or less than the number
+ of NFS calls received (which statistic is available elsewhere).
+ However this is a more accurate and less workload-dependent measure
+ of how much CPU load is being placed on the sunrpc server layer
+ due to NFS network traffic.
+
+sockets-enqueued
+ Counts how many times an NFS transport is enqueued to wait for
+ an nfsd thread to service it, i.e. no nfsd thread was considered
+ available.
+
+ The circumstance this statistic tracks indicates that there was NFS
+ network-facing work to be done but it couldn't be done immediately,
+ thus introducing a small delay in servicing NFS calls. The ideal
+ rate of change for this counter is zero; significantly non-zero
+ values may indicate a performance limitation.
+
+ This can happen either because there are too few nfsd threads in the
+ thread pool for the NFS workload (the workload is thread-limited),
+ or because the NFS workload needs more CPU time than is available in
+ the thread pool (the workload is CPU-limited). In the former case,
+ configuring more nfsd threads will probably improve the performance
+ of the NFS workload. In the latter case, the sunrpc server layer is
+ already choosing not to wake idle nfsd threads because there are too
+ many nfsd threads which want to run but cannot, so configuring more
+ nfsd threads will make no difference whatsoever. The overloads-avoided
+ statistic (see below) can be used to distinguish these cases.
+
+threads-woken
+ Counts how many times an idle nfsd thread is woken to try to
+ receive some data from an NFS transport.
+
+ This statistic tracks the circumstance where incoming
+ network-facing NFS work is being handled quickly, which is a good
+ thing. The ideal rate of change for this counter will be close
+ to but less than the rate of change of the packets-arrived counter.
+
+overloads-avoided
+ Counts how many times the sunrpc server layer chose not to wake an
+ nfsd thread, despite the presence of idle nfsd threads, because
+ too many nfsd threads had been recently woken but could not get
+ enough CPU time to actually run.
+
+ This statistic counts a circumstance where the sunrpc layer
+ heuristically avoids overloading the CPU scheduler with too many
+ runnable nfsd threads. The ideal rate of change for this counter
+ is zero. Significant non-zero values indicate that the workload
+ is CPU limited. Usually this is associated with heavy CPU usage
+ on all the CPUs in the nfsd thread pool.
+
+ If a sustained large overloads-avoided rate is detected on a pool,
+ the top(1) utility should be used to check for the following
+ pattern of CPU usage on all the CPUs associated with the given
+ nfsd thread pool.
+
+ - %us ~= 0 (as you're *NOT* running applications on your NFS server)
+
+ - %wa ~= 0
+
+ - %id ~= 0
+
+ - %sy + %hi + %si ~= 100
+
+ If this pattern is seen, configuring more nfsd threads will *not*
+ improve the performance of the workload. If this patten is not
+ seen, then something more subtle is wrong.
+
+threads-timedout
+ Counts how many times an nfsd thread triggered an idle timeout,
+ i.e. was not woken to handle any incoming network packets for
+ some time.
+
+ This statistic counts a circumstance where there are more nfsd
+ threads configured than can be used by the NFS workload. This is
+ a clue that the number of nfsd threads can be reduced without
+ affecting performance. Unfortunately, it's only a clue and not
+ a strong indication, for a couple of reasons:
+
+ - Currently the rate at which the counter is incremented is quite
+ slow; the idle timeout is 60 minutes. Unless the NFS workload
+ remains constant for hours at a time, this counter is unlikely
+ to be providing information that is still useful.
+
+ - It is usually a wise policy to provide some slack,
+ i.e. configure a few more nfsds than are currently needed,
+ to allow for future spikes in load.
+
+
+Note that incoming packets on NFS transports will be dealt with in
+one of three ways. An nfsd thread can be woken (threads-woken counts
+this case), or the transport can be enqueued for later attention
+(sockets-enqueued counts this case), or the packet can be temporarily
+deferred because the transport is currently being used by an nfsd
+thread. This last case is not very interesting and is not explicitly
+counted, but can be inferred from the other counters thus:
+
+packets-deferred = packets-arrived - ( sockets-enqueued + threads-woken )
+
+
+More
+----
+Descriptions of the other statistics file should go here.
+
+
+Greg Banks <gnb@sgi.com>
+26 Mar 2009
--- /dev/null
+NFSv4.1 Server Implementation
+
+Server support for minorversion 1 can be controlled using the
+/proc/fs/nfsd/versions control file. The string output returned
+by reading this file will contain either "+4.1" or "-4.1"
+correspondingly.
+
+Currently, server support for minorversion 1 is disabled by default.
+It can be enabled at run time by writing the string "+4.1" to
+the /proc/fs/nfsd/versions control file. Note that to write this
+control file, the nfsd service must be taken down. Use your user-mode
+nfs-utils to set this up; see rpc.nfsd(8)
+
+The NFSv4 minorversion 1 (NFSv4.1) implementation in nfsd is based
+on the latest NFSv4.1 Internet Draft:
+http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-29
+
+From the many new features in NFSv4.1 the current implementation
+focuses on the mandatory-to-implement NFSv4.1 Sessions, providing
+"exactly once" semantics and better control and throttling of the
+resources allocated for each client.
+
+Other NFSv4.1 features, Parallel NFS operations in particular,
+are still under development out of tree.
+See http://wiki.linux-nfs.org/wiki/index.php/PNFS_prototype_design
+for more information.
+
+The table below, taken from the NFSv4.1 document, lists
+the operations that are mandatory to implement (REQ), optional
+(OPT), and NFSv4.0 operations that are required not to implement (MNI)
+in minor version 1. The first column indicates the operations that
+are not supported yet by the linux server implementation.
+
+The OPTIONAL features identified and their abbreviations are as follows:
+ pNFS Parallel NFS
+ FDELG File Delegations
+ DDELG Directory Delegations
+
+The following abbreviations indicate the linux server implementation status.
+ I Implemented NFSv4.1 operations.
+ NS Not Supported.
+ NS* unimplemented optional feature.
+ P pNFS features implemented out of tree.
+ PNS pNFS features that are not supported yet (out of tree).
+
+Operations
+
+ +----------------------+------------+--------------+----------------+
+ | Operation | REQ, REC, | Feature | Definition |
+ | | OPT, or | (REQ, REC, | |
+ | | MNI | or OPT) | |
+ +----------------------+------------+--------------+----------------+
+ | ACCESS | REQ | | Section 18.1 |
+NS | BACKCHANNEL_CTL | REQ | | Section 18.33 |
+NS | BIND_CONN_TO_SESSION | REQ | | Section 18.34 |
+ | CLOSE | REQ | | Section 18.2 |
+ | COMMIT | REQ | | Section 18.3 |
+ | CREATE | REQ | | Section 18.4 |
+I | CREATE_SESSION | REQ | | Section 18.36 |
+NS*| DELEGPURGE | OPT | FDELG (REQ) | Section 18.5 |
+ | DELEGRETURN | OPT | FDELG, | Section 18.6 |
+ | | | DDELG, pNFS | |
+ | | | (REQ) | |
+NS | DESTROY_CLIENTID | REQ | | Section 18.50 |
+I | DESTROY_SESSION | REQ | | Section 18.37 |
+I | EXCHANGE_ID | REQ | | Section 18.35 |
+NS | FREE_STATEID | REQ | | Section 18.38 |
+ | GETATTR | REQ | | Section 18.7 |
+P | GETDEVICEINFO | OPT | pNFS (REQ) | Section 18.40 |
+P | GETDEVICELIST | OPT | pNFS (OPT) | Section 18.41 |
+ | GETFH | REQ | | Section 18.8 |
+NS*| GET_DIR_DELEGATION | OPT | DDELG (REQ) | Section 18.39 |
+P | LAYOUTCOMMIT | OPT | pNFS (REQ) | Section 18.42 |
+P | LAYOUTGET | OPT | pNFS (REQ) | Section 18.43 |
+P | LAYOUTRETURN | OPT | pNFS (REQ) | Section 18.44 |
+ | LINK | OPT | | Section 18.9 |
+ | LOCK | REQ | | Section 18.10 |
+ | LOCKT | REQ | | Section 18.11 |
+ | LOCKU | REQ | | Section 18.12 |
+ | LOOKUP | REQ | | Section 18.13 |
+ | LOOKUPP | REQ | | Section 18.14 |
+ | NVERIFY | REQ | | Section 18.15 |
+ | OPEN | REQ | | Section 18.16 |
+NS*| OPENATTR | OPT | | Section 18.17 |
+ | OPEN_CONFIRM | MNI | | N/A |
+ | OPEN_DOWNGRADE | REQ | | Section 18.18 |
+ | PUTFH | REQ | | Section 18.19 |
+ | PUTPUBFH | REQ | | Section 18.20 |
+ | PUTROOTFH | REQ | | Section 18.21 |
+ | READ | REQ | | Section 18.22 |
+ | READDIR | REQ | | Section 18.23 |
+ | READLINK | OPT | | Section 18.24 |
+NS | RECLAIM_COMPLETE | REQ | | Section 18.51 |
+ | RELEASE_LOCKOWNER | MNI | | N/A |
+ | REMOVE | REQ | | Section 18.25 |
+ | RENAME | REQ | | Section 18.26 |
+ | RENEW | MNI | | N/A |
+ | RESTOREFH | REQ | | Section 18.27 |
+ | SAVEFH | REQ | | Section 18.28 |
+ | SECINFO | REQ | | Section 18.29 |
+NS | SECINFO_NO_NAME | REC | pNFS files | Section 18.45, |
+ | | | layout (REQ) | Section 13.12 |
+I | SEQUENCE | REQ | | Section 18.46 |
+ | SETATTR | REQ | | Section 18.30 |
+ | SETCLIENTID | MNI | | N/A |
+ | SETCLIENTID_CONFIRM | MNI | | N/A |
+NS | SET_SSV | REQ | | Section 18.47 |
+NS | TEST_STATEID | REQ | | Section 18.48 |
+ | VERIFY | REQ | | Section 18.31 |
+NS*| WANT_DELEGATION | OPT | FDELG (OPT) | Section 18.49 |
+ | WRITE | REQ | | Section 18.32 |
+
+Callback Operations
+
+ +-------------------------+-----------+-------------+---------------+
+ | Operation | REQ, REC, | Feature | Definition |
+ | | OPT, or | (REQ, REC, | |
+ | | MNI | or OPT) | |
+ +-------------------------+-----------+-------------+---------------+
+ | CB_GETATTR | OPT | FDELG (REQ) | Section 20.1 |
+P | CB_LAYOUTRECALL | OPT | pNFS (REQ) | Section 20.3 |
+NS*| CB_NOTIFY | OPT | DDELG (REQ) | Section 20.4 |
+P | CB_NOTIFY_DEVICEID | OPT | pNFS (OPT) | Section 20.12 |
+NS*| CB_NOTIFY_LOCK | OPT | | Section 20.11 |
+NS*| CB_PUSH_DELEG | OPT | FDELG (OPT) | Section 20.5 |
+ | CB_RECALL | OPT | FDELG, | Section 20.2 |
+ | | | DDELG, pNFS | |
+ | | | (REQ) | |
+NS*| CB_RECALL_ANY | OPT | FDELG, | Section 20.6 |
+ | | | DDELG, pNFS | |
+ | | | (REQ) | |
+NS | CB_RECALL_SLOT | REQ | | Section 20.8 |
+NS*| CB_RECALLABLE_OBJ_AVAIL | OPT | DDELG, pNFS | Section 20.7 |
+ | | | (REQ) | |
+I | CB_SEQUENCE | OPT | FDELG, | Section 20.9 |
+ | | | DDELG, pNFS | |
+ | | | (REQ) | |
+NS*| CB_WANTS_CANCELLED | OPT | FDELG, | Section 20.10 |
+ | | | DDELG, pNFS | |
+ | | | (REQ) | |
+ +-------------------------+-----------+-------------+---------------+
+
+Implementation notes:
+
+EXCHANGE_ID:
+* only SP4_NONE state protection supported
+* implementation ids are ignored
+
+CREATE_SESSION:
+* backchannel attributes are ignored
+* backchannel security parameters are ignored
+
+SEQUENCE:
+* no support for dynamic slot table renegotiation (optional)
+
+nfsv4.1 COMPOUND rules:
+The following cases aren't supported yet:
+* Enforcing of NFS4ERR_NOT_ONLY_OP for: BIND_CONN_TO_SESSION, CREATE_SESSION,
+ DESTROY_CLIENTID, DESTROY_SESSION, EXCHANGE_ID.
+* DESTROY_SESSION MUST be the final operation in the COMPOUND request.
+
--- /dev/null
+NILFS2
+------
+
+NILFS2 is a log-structured file system (LFS) supporting continuous
+snapshotting. In addition to versioning capability of the entire file
+system, users can even restore files mistakenly overwritten or
+destroyed just a few seconds ago. Since NILFS2 can keep consistency
+like conventional LFS, it achieves quick recovery after system
+crashes.
+
+NILFS2 creates a number of checkpoints every few seconds or per
+synchronous write basis (unless there is no change). Users can select
+significant versions among continuously created checkpoints, and can
+change them into snapshots which will be preserved until they are
+changed back to checkpoints.
+
+There is no limit on the number of snapshots until the volume gets
+full. Each snapshot is mountable as a read-only file system
+concurrently with its writable mount, and this feature is convenient
+for online backup.
+
+The userland tools are included in nilfs-utils package, which is
+available from the following download page. At least "mkfs.nilfs2",
+"mount.nilfs2", "umount.nilfs2", and "nilfs_cleanerd" (so called
+cleaner or garbage collector) are required. Details on the tools are
+described in the man pages included in the package.
+
+Project web page: http://www.nilfs.org/en/
+Download page: http://www.nilfs.org/en/download.html
+Git tree web page: http://www.nilfs.org/git/
+NILFS mailing lists: http://www.nilfs.org/mailman/listinfo/users
+
+Caveats
+=======
+
+Features which NILFS2 does not support yet:
+
+ - atime
+ - extended attributes
+ - POSIX ACLs
+ - quotas
+ - writable snapshots
+ - remote backup (CDP)
+ - data integrity
+ - defragmentation
+
+Mount options
+=============
+
+NILFS2 supports the following mount options:
+(*) == default
+
+barrier=on(*) This enables/disables barriers. barrier=off disables
+ it, barrier=on enables it.
+errors=continue(*) Keep going on a filesystem error.
+errors=remount-ro Remount the filesystem read-only on an error.
+errors=panic Panic and halt the machine if an error occurs.
+cp=n Specify the checkpoint-number of the snapshot to be
+ mounted. Checkpoints and snapshots are listed by lscp
+ user command. Only the checkpoints marked as snapshot
+ are mountable with this option. Snapshot is read-only,
+ so a read-only mount option must be specified together.
+order=relaxed(*) Apply relaxed order semantics that allows modified data
+ blocks to be written to disk without making a
+ checkpoint if no metadata update is going. This mode
+ is equivalent to the ordered data mode of the ext3
+ filesystem except for the updates on data blocks still
+ conserve atomicity. This will improve synchronous
+ write performance for overwriting.
+order=strict Apply strict in-order semantics that preserves sequence
+ of all file operations including overwriting of data
+ blocks. That means, it is guaranteed that no
+ overtaking of events occurs in the recovered file
+ system after a crash.
+
+NILFS2 usage
+============
+
+To use nilfs2 as a local file system, simply:
+
+ # mkfs -t nilfs2 /dev/block_device
+ # mount -t nilfs2 /dev/block_device /dir
+
+This will also invoke the cleaner through the mount helper program
+(mount.nilfs2).
+
+Checkpoints and snapshots are managed by the following commands.
+Their manpages are included in the nilfs-utils package above.
+
+ lscp list checkpoints or snapshots.
+ mkcp make a checkpoint or a snapshot.
+ chcp change an existing checkpoint to a snapshot or vice versa.
+ rmcp invalidate specified checkpoint(s).
+
+To mount a snapshot,
+
+ # mount -t nilfs2 -r -o cp=<cno> /dev/block_device /snap_dir
+
+where <cno> is the checkpoint number of the snapshot.
+
+To unmount the NILFS2 mount point or snapshot, simply:
+
+ # umount /dir
+
+Then, the cleaner daemon is automatically shut down by the umount
+helper program (umount.nilfs2).
+
+Disk format
+===========
+
+A nilfs2 volume is equally divided into a number of segments except
+for the super block (SB) and segment #0. A segment is the container
+of logs. Each log is composed of summary information blocks, payload
+blocks, and an optional super root block (SR):
+
+ ______________________________________________________
+ | |SB| | Segment | Segment | Segment | ... | Segment | |
+ |_|__|_|____0____|____1____|____2____|_____|____N____|_|
+ 0 +1K +4K +8M +16M +24M +(8MB x N)
+ . . (Typical offsets for 4KB-block)
+ . .
+ .______________________.
+ | log | log |... | log |
+ |__1__|__2__|____|__m__|
+ . .
+ . .
+ . .
+ .______________________________.
+ | Summary | Payload blocks |SR|
+ |_blocks__|_________________|__|
+
+The payload blocks are organized per file, and each file consists of
+data blocks and B-tree node blocks:
+
+ |<--- File-A --->|<--- File-B --->|
+ _______________________________________________________________
+ | Data blocks | B-tree blocks | Data blocks | B-tree blocks | ...
+ _|_____________|_______________|_____________|_______________|_
+
+
+Since only the modified blocks are written in the log, it may have
+files without data blocks or B-tree node blocks.
+
+The organization of the blocks is recorded in the summary information
+blocks, which contains a header structure (nilfs_segment_summary), per
+file structures (nilfs_finfo), and per block structures (nilfs_binfo):
+
+ _________________________________________________________________________
+ | Summary | finfo | binfo | ... | binfo | finfo | binfo | ... | binfo |...
+ |_blocks__|___A___|_(A,1)_|_____|(A,Na)_|___B___|_(B,1)_|_____|(B,Nb)_|___
+
+
+The logs include regular files, directory files, symbolic link files
+and several meta data files. The mata data files are the files used
+to maintain file system meta data. The current version of NILFS2 uses
+the following meta data files:
+
+ 1) Inode file (ifile) -- Stores on-disk inodes
+ 2) Checkpoint file (cpfile) -- Stores checkpoints
+ 3) Segment usage file (sufile) -- Stores allocation state of segments
+ 4) Data address translation file -- Maps virtual block numbers to usual
+ (DAT) block numbers. This file serves to
+ make on-disk blocks relocatable.
+
+The following figure shows a typical organization of the logs:
+
+ _________________________________________________________________________
+ | Summary | regular file | file | ... | ifile | cpfile | sufile | DAT |SR|
+ |_blocks__|_or_directory_|_______|_____|_______|________|________|_____|__|
+
+
+To stride over segment boundaries, this sequence of files may be split
+into multiple logs. The sequence of logs that should be treated as
+logically one log, is delimited with flags marked in the segment
+summary. The recovery code of nilfs2 looks this boundary information
+to ensure atomicity of updates.
+
+The super root block is inserted for every checkpoints. It includes
+three special inodes, inodes for the DAT, cpfile, and sufile. Inodes
+of regular files, directories, symlinks and other special files, are
+included in the ifile. The inode of ifile itself is included in the
+corresponding checkpoint entry in the cpfile. Thus, the hierarchy
+among NILFS2 files can be depicted as follows:
+
+ Super block (SB)
+ |
+ v
+ Super root block (the latest cno=xx)
+ |-- DAT
+ |-- sufile
+ `-- cpfile
+ |-- ifile (cno=c1)
+ |-- ifile (cno=c2) ---- file (ino=i1)
+ : : |-- file (ino=i2)
+ `-- ifile (cno=xx) |-- file (ino=i3)
+ : :
+ `-- file (ino=yy)
+ ( regular file, directory, or symlink )
+
+For detail on the format of each file, please see include/linux/nilfs2_fs.h.
--- /dev/null
+Kernel driver g760a
+===================
+
+Supported chips:
+ * Global Mixed-mode Technology Inc. G760A
+ Prefix: 'g760a'
+ Datasheet: Publicly available at the GMT website
+ http://www.gmt.com.tw/datasheet/g760a.pdf
+
+Author: Herbert Valerio Riedel <hvr@gnu.org>
+
+Description
+-----------
+
+The GMT G760A Fan Speed PWM Controller is connected directly to a fan
+and performs closed-loop control of the fan speed.
+
+The fan speed is programmed by setting the period via 'pwm1' of two
+consecutive speed pulses. The period is defined in terms of clock
+cycle counts of an assumed 32kHz clock source.
+
+Setting a period of 0 stops the fan; setting the period to 255 sets
+fan to maximum speed.
+
+The measured fan rotation speed returned via 'fan1_input' is derived
+from the measured speed pulse period by assuming again a 32kHz clock
+source and a 2 pulse-per-revolution fan.
+
+The 'alarms' file provides access to the two alarm bits provided by
+the G760A chip's status register: Bit 0 is set when the actual fan
+speed differs more than 20% with respect to the programmed fan speed;
+bit 1 is set when fan speed is below 1920 RPM.
+
+The g760a driver will not update its values more frequently than every
+other second; reading them more often will do no harm, but will return
+'old' values.
---------------------
2.1. Modules
-------
- To get the device working, you have to load the proper kernel module. You
- can do this using
- modprobe modulename
- where modulename is ser_gigaset (M101), usb_gigaset (M105), or
- bas_gigaset (direct USB connection to the base).
+ For the devices to work, the proper kernel modules have to be loaded.
+ This normally happens automatically when the system detects the USB
+ device (base, M105) or when the line discipline is attached (M101). It
+ can also be triggered manually using the modprobe(8) command, for example
+ for troubleshooting or to pass module parameters.
The module ser_gigaset provides a serial line discipline N_GIGASET_M101
- which drives the device through the regular serial line driver. To use it,
- run the Gigaset M101 daemon "gigasetm101d" (also available from
- http://sourceforge.net/projects/gigaset307x/) with the device file of the
- RS232 port to the M101 as an argument, for example:
- gigasetm101d /dev/ttyS1
- This will open the device file, set its line discipline to N_GIGASET_M101,
- and then sleep in the background, keeping the device open so that the
- line discipline remains active. To deactivate it, kill the daemon, for
- example with
- killall gigasetm101d
- before disconnecting the device.
+ which drives the device through the regular serial line driver. It must
+ be attached to the serial line to which the M101 is connected with the
+ ldattach(8) command (requires util-linux-ng release 2.14 or later), for
+ example:
+ ldattach GIGASET_M101 /dev/ttyS1
+ This will open the device file, attach the line discipline to it, and
+ then sleep in the background, keeping the device open so that the line
+ discipline remains active. To deactivate it, kill the daemon, for example
+ with
+ killall ldattach
+ before disconnecting the device. To have this happen automatically at
+ system startup/shutdown on an LSB compatible system, create and activate
+ an appropriate LSB startup script /etc/init.d/gigaset. (The init name
+ 'gigaset' is officially assigned to this project by LANANA.)
+ Alternatively, just add the 'ldattach' command line to /etc/rc.local.
2.2. Device nodes for user space programs
------------------------------------
operation (for wireless access to the base), but are needed for access
to the M105's own configuration mode (registration to the base, baudrate
and line format settings, device status queries) via the gigacontr
- utility. Their use is disabled in the driver by default for safety
- reasons but can be enabled by setting the kernel configuration option
- "Support for undocumented USB requests" (GIGASET_UNDOCREQ) to "Y" and
- recompiling.
+ utility. Their use is controlled by the kernel configuration option
+ "Support for undocumented USB requests" (CONFIG_GIGASET_UNDOCREQ). If you
+ encounter error code -ENOTTY when trying to use some features of the
+ M105, try setting that option to "y" via 'make {x,menu}config' and
+ recompiling the driver.
3. Troubleshooting
Solution:
Select Unimodem mode for all DECT data adapters. (see section 2.4.)
+ Problem:
+ You want to configure your USB DECT data adapter (M105) but gigacontr
+ reports an error: "/dev/ttyGU0: Inappropriate ioctl for device".
+ Solution:
+ Recompile the usb_gigaset driver with the kernel configuration option
+ CONFIG_GIGASET_UNDOCREQ set to 'y'. (see section 2.6.)
+
3.2. Telling the driver to provide more information
----------------------------------------------
Building the driver with the "Gigaset debugging" kernel configuration
1,0: use 1st APIC table
default: 0
- acpi_sleep= [HW,ACPI] Sleep options
- Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
- old_ordering, s4_nonvs }
- See Documentation/power/video.txt for information on
- s3_bios and s3_mode.
- s3_beep is for debugging; it makes the PC's speaker beep
- as soon as the kernel's real-mode entry point is called.
- s4_nohwsig prevents ACPI hardware signature from being
- used during resume from hibernation.
- old_ordering causes the ACPI 1.0 ordering of the _PTS
- control method, with respect to putting devices into
- low power states, to be enforced (the ACPI 2.0 ordering
- of _PTS is used by default).
- s4_nonvs prevents the kernel from saving/restoring the
- ACPI NVS memory during hibernation.
-
- acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
- Format: { level | edge | high | low }
-
- acpi_irq_balance [HW,ACPI]
- ACPI will balance active IRQs
- default in APIC mode
-
- acpi_irq_nobalance [HW,ACPI]
- ACPI will not move active IRQs (default)
- default in PIC mode
-
- acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
- use by PCI
- Format: <irq>,<irq>...
-
- acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
- Format: <irq>,<irq>...
-
- acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
-
- acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
- Format: To spoof as Windows 98: ="Microsoft Windows"
-
- acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
- acpi_osi="string1" # add string1 -- only one string
- acpi_osi="!string2" # remove built-in string2
- acpi_osi= # disable all strings
-
- acpi_serialize [HW,ACPI] force serialization of AML methods
-
- acpi_skip_timer_override [HW,ACPI]
- Recognize and ignore IRQ0/pin2 Interrupt Override.
- For broken nForce2 BIOS resulting in XT-PIC timer.
- acpi_use_timer_override [HW,ACPI]
- Use timer override. For some broken Nvidia NF5 boards
- that require a timer override, but don't have
- HPET
-
acpi_backlight= [HW,ACPI]
acpi_backlight=vendor
acpi_backlight=video
(e.g. thinkpad_acpi, sony_acpi, etc.) instead
of the ACPI video.ko driver.
- acpi_display_output= [HW,ACPI]
- acpi_display_output=vendor
- acpi_display_output=video
- See above.
-
acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
Format: <int>
unusable. The "log_buf_len" parameter may be useful
if you need to capture more output.
+ acpi_display_output= [HW,ACPI]
+ acpi_display_output=vendor
+ acpi_display_output=video
+ See above.
+
+ acpi_irq_balance [HW,ACPI]
+ ACPI will balance active IRQs
+ default in APIC mode
+
+ acpi_irq_nobalance [HW,ACPI]
+ ACPI will not move active IRQs (default)
+ default in PIC mode
+
+ acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
+ Format: <irq>,<irq>...
+
+ acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
+ use by PCI
+ Format: <irq>,<irq>...
+
+ acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
+
+ acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
+ Format: To spoof as Windows 98: ="Microsoft Windows"
+
+ acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
+ acpi_osi="string1" # add string1 -- only one string
+ acpi_osi="!string2" # remove built-in string2
+ acpi_osi= # disable all strings
+
+ acpi_pm_good [X86-32,X86-64]
+ Override the pmtimer bug detection: force the kernel
+ to assume that this machine's pmtimer latches its value
+ and always returns good values.
+
acpi.power_nocheck= [HW,ACPI]
Format: 1/0 enable/disable the check of power state.
On some bogus BIOS the _PSC object/_STA object of
power state again in power transition.
1 : disable the power state check
- acpi_pm_good [X86-32,X86-64]
- Override the pmtimer bug detection: force the kernel
- to assume that this machine's pmtimer latches its value
- and always returns good values.
-
acpi_enforce_resources= [ACPI]
{ strict | lax | no }
Check for resource conflicts between native drivers
no: ACPI OperationRegions are not marked as reserved,
no further checks are performed.
- agp= [AGP]
- { off | try_unsupported }
- off: disable AGP support
- try_unsupported: try to drive unsupported chipsets
- (may crash computer or cause data corruption)
-
- enable_timer_pin_1 [i386,x86-64]
- Enable PIN 1 of APIC timer
- Can be useful to work around chipset bugs
- (in particular on some ATI chipsets).
- The kernel tries to set a reasonable default.
-
- disable_timer_pin_1 [i386,x86-64]
- Disable PIN 1 of APIC timer
- Can be useful to work around chipset bugs.
-
ad1848= [HW,OSS]
Format: <io>,<irq>,<dma>,<dma2>,<type>
Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
See also header of sound/oss/aedsp16.c.
+ agp= [AGP]
+ { off | try_unsupported }
+ off: disable AGP support
+ try_unsupported: try to drive unsupported chipsets
+ (may crash computer or cause data corruption)
+
aha152x= [HW,SCSI]
See Documentation/scsi/aha152x.txt.
possible to determine what the correct size should be.
This option provides an override for these situations.
- security= [SECURITY] Choose a security module to enable at boot.
- If this boot parameter is not specified, only the first
- security module asking for security registration will be
- loaded. An invalid security module name will be treated
- as if no module has been chosen.
-
capability.disable=
[SECURITY] Disable capabilities. This would normally
be used only if an alternative security model is to be
Range: 0 - 8192
Default: 64
- dma_debug=off If the kernel is compiled with DMA_API_DEBUG support
- this option disables the debugging code at boot.
-
- dma_debug_entries=<number>
- This option allows to tune the number of preallocated
- entries for DMA-API debugging code. One entry is
- required per DMA-API allocation. Use this if the
- DMA-API debugging code disables itself because the
- architectural default is too low.
-
- hpet= [X86-32,HPET] option to control HPET usage
- Format: { enable (default) | disable | force |
- verbose }
- disable: disable HPET and use PIT instead
- force: allow force enabled of undocumented chips (ICH4,
- VIA, nVidia)
- verbose: show contents of HPET registers during setup
-
com20020= [HW,NET] ARCnet - COM20020 chipset
Format:
<io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
console=brl,ttyS0
For now, only VisioBraille is supported.
- earlycon= [KNL] Output early console device and options.
- uart[8250],io,<addr>[,options]
- uart[8250],mmio,<addr>[,options]
- Start an early, polled-mode console on the 8250/16550
- UART at the specified I/O port or MMIO address.
- The options are the same as for ttyS, above.
-
- no_console_suspend
- [HW] Never suspend the console
- Disable suspending of consoles during suspend and
- hibernate operations. Once disabled, debugging
- messages can reach various consoles while the rest
- of the system is being put to sleep (ie, while
- debugging driver suspend/resume hooks). This may
- not work reliably with all consoles, but is known
- to work with serial and VGA consoles.
-
coredump_filter=
[KNL] Change the default value for
/proc/<pid>/coredump_filter.
Format: <area>[,<node>]
See also Documentation/networking/decnet.txt.
- vt.default_blu= [VT]
- Format: <blue0>,<blue1>,<blue2>,...,<blue15>
- Change the default blue palette of the console.
- This is a 16-member array composed of values
- ranging from 0-255.
-
- vt.default_grn= [VT]
- Format: <green0>,<green1>,<green2>,...,<green15>
- Change the default green palette of the console.
- This is a 16-member array composed of values
- ranging from 0-255.
-
- vt.default_red= [VT]
- Format: <red0>,<red1>,<red2>,...,<red15>
- Change the default red palette of the console.
- This is a 16-member array composed of values
- ranging from 0-255.
-
- vt.default_utf8=
- [VT]
- Format=<0|1>
- Set system-wide default UTF-8 mode for all tty's.
- Default is 1, i.e. UTF-8 mode is enabled for all
- newly opened terminals.
+ default_hugepagesz=
+ [same as hugepagesz=] The size of the default
+ HugeTLB page size. This is the size represented by
+ the legacy /proc/ hugepages APIs, used for SHM, and
+ default size when mounting hugetlbfs filesystems.
+ Defaults to the default architecture's huge page size
+ if not specified.
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
Documentation/serial/digiepca.txt.
disable_mtrr_cleanup [X86]
- enable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
to discrete, to make X server driver able to add WB
- entry later. This parameter enables/disables that.
-
- mtrr_chunk_size=nn[KMG] [X86]
- used for mtrr cleanup. It is largest continous chunk
- that could hold holes aka. UC entries.
-
- mtrr_gran_size=nn[KMG] [X86]
- Used for mtrr cleanup. It is granularity of mtrr block.
- Default is 1.
- Large value could prevent small alignment from
- using up MTRRs.
-
- mtrr_spare_reg_nr=n [X86]
- Format: <integer>
- Range: 0,7 : spare reg number
- Default : 1
- Used for mtrr cleanup. It is spare mtrr entries number.
- Set to 2 or more if your graphical card needs more.
+ entry later. This parameter disables that.
disable_mtrr_trim [X86, Intel and AMD only]
By default the kernel will trim any uncacheable
MTRR settings. This parameter disables that behavior,
possibly causing your machine to run very slowly.
+ disable_timer_pin_1 [i386,x86-64]
+ Disable PIN 1 of APIC timer
+ Can be useful to work around chipset bugs.
+
dmasound= [HW,OSS] Sound subsystem buffers
+ dma_debug=off If the kernel is compiled with DMA_API_DEBUG support,
+ this option disables the debugging code at boot.
+
+ dma_debug_entries=<number>
+ This option allows to tune the number of preallocated
+ entries for DMA-API debugging code. One entry is
+ required per DMA-API allocation. Use this if the
+ DMA-API debugging code disables itself because the
+ architectural default is too low.
+
dscc4.setup= [NET]
dtc3181e= [HW,SCSI]
+ dynamic_printk Enables pr_debug()/dev_dbg() calls if
+ CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
+ These can also be switched on/off via
+ <debugfs>/dynamic_printk/modules
+
+ earlycon= [KNL] Output early console device and options.
+ uart[8250],io,<addr>[,options]
+ uart[8250],mmio,<addr>[,options]
+ Start an early, polled-mode console on the 8250/16550
+ UART at the specified I/O port or MMIO address.
+ The options are the same as for ttyS, above.
+
earlyprintk= [X86-32,X86-64,SH,BLACKFIN]
earlyprintk=vga
earlyprintk=serial[,ttySn[,baudrate]]
pass this option to capture kernel.
See Documentation/kdump/kdump.txt for details.
+ enable_mtrr_cleanup [X86]
+ The kernel tries to adjust MTRR layout from continuous
+ to discrete, to make X server driver able to add WB
+ entry later. This parameter enables that.
+
+ enable_timer_pin_1 [i386,x86-64]
+ Enable PIN 1 of APIC timer
+ Can be useful to work around chipset bugs
+ (in particular on some ATI chipsets).
+ The kernel tries to set a reasonable default.
+
enforcing [SELINUX] Set initial enforcing status.
Format: {"0" | "1"}
See security/selinux/Kconfig help text.
hisax= [HW,ISDN]
See Documentation/isdn/README.HiSax.
+ hlt [BUGS=ARM,SH]
+
+ hpet= [X86-32,HPET] option to control HPET usage
+ Format: { enable (default) | disable | force |
+ verbose }
+ disable: disable HPET and use PIT instead
+ force: allow force enabled of undocumented chips (ICH4,
+ VIA, nVidia)
+ verbose: show contents of HPET registers during setup
+
hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
On x86-64 and powerpc, this option can be specified
(when the CPU supports the "pdpe1gb" cpuinfo flag)
Note that 1GB pages can only be allocated at boot time
using hugepages= and not freed afterwards.
- default_hugepagesz=
- [same as hugepagesz=] The size of the default
- HugeTLB page size. This is the size represented by
- the legacy /proc/ hugepages APIs, used for SHM, and
- default size when mounting hugetlbfs filesystems.
- Defaults to the default architecture's huge page size
- if not specified.
-
- hlt [BUGS=ARM,SH]
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
terminal devices. Valid values: 0..8
idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
See Documentation/ide/ide.txt.
+ ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
+ Claim all unknown PCI IDE storage controllers.
+
idle= [X86]
Format: idle=poll, idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly
In such case C2/C3 won't be used again.
idle=nomwait: Disable mwait for CPU C-states
- ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
- Claim all unknown PCI IDE storage controllers.
-
ignore_loglevel [KNL]
Ignore loglevel setting - this will print /all/
kernel messages to the console. Useful for debugging.
inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
Format: <irq>
- inttest= [IA64]
-
- iomem= Disable strict checking of access to MMIO memory
- strict regions from userspace.
- relaxed
-
- iommu= [x86]
- off
- force
- noforce
- biomerge
- panic
- nopanic
- merge
- nomerge
- forcesac
- soft
-
-
intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
on
Enable intel iommu driver.
result in a hardware IOTLB flush operation as opposed
to batching them for performance.
+ inttest= [IA64]
+
+ iomem= Disable strict checking of access to MMIO memory
+ strict regions from userspace.
+ relaxed
+
+ iommu= [x86]
+ off
+ force
+ noforce
+ biomerge
+ panic
+ nopanic
+ merge
+ nomerge
+ forcesac
+ soft
+
+ io7= [HW] IO7 for Marvel based alpha systems
+ See comment before marvel_specify_io7 in
+ arch/alpha/kernel/core_marvel.c.
+
io_delay= [X86-32,X86-64] I/O delay method
0x80
Standard port 0x80 based delay
none
No delay
- io7= [HW] IO7 for Marvel based alpha systems
- See comment before marvel_specify_io7 in
- arch/alpha/kernel/core_marvel.c.
-
ip= [IP_PNP]
See Documentation/filesystems/nfsroot.txt.
ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
See header of drivers/scsi/ips.c.
- ports= [IP_VS_FTP] IPVS ftp helper module
- Default is 21.
- Up to 8 (IP_VS_APP_MAX_PORTS) ports
- may be specified.
- Format: <port>,<port>....
-
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
js= [HW,JOY] Analog joystick
See Documentation/input/joystick.txt.
+ keepinitrd [HW,ARM]
+
kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
specifies the amount of memory usable by the kernel
for non-movable allocations. The requested amount is
higher than default (KMEMTRACE_N_SUBBUFS in code) if
you experience buffer overruns.
- movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
- is similar to kernelcore except it specifies the
- amount of memory used for migratable allocations.
- If both kernelcore and movablecore is specified,
- then kernelcore will be at *least* the specified
- value but may be more. If movablecore on its own
- is specified, the administrator must be careful
- that the amount of memory usable for all allocations
- is not too small.
-
- keepinitrd [HW,ARM]
-
- kstack=N [X86-32,X86-64] Print N words from the kernel stack
- in oops dumps.
-
kgdboc= [HW] kgdb over consoles.
Requires a tty driver that supports console polling.
(only serial suported for now)
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
+ kstack=N [X86-32,X86-64] Print N words from the kernel stack
+ in oops dumps.
+
l2cr= [PPC]
l3cr= [PPC]
(machvec) in a generic kernel.
Example: machvec=hpzx1_swiotlb
- max_loop= [LOOP] Maximum number of loopback devices that can
- be mounted
- Format: <1-256>
+ max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater
+ than or equal to this physical address is ignored.
maxcpus= [SMP] Maximum number of processors that an SMP kernel
should make use of. maxcpus=n : n >= 0 limits the
it is equivalent to "nosmp", which also disables
the IO APIC.
- max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater than
- or equal to this physical address is ignored.
+ max_loop= [LOOP] Maximum number of loopback devices that can
+ be mounted
+ Format: <1-256>
max_luns= [SCSI] Maximum number of LUNs to probe.
Should be between 1 and 2^32-1.
mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
reporting absolute coordinates, such as tablets
+ movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
+ is similar to kernelcore except it specifies the
+ amount of memory used for migratable allocations.
+ If both kernelcore and movablecore is specified,
+ then kernelcore will be at *least* the specified
+ value but may be more. If movablecore on its own
+ is specified, the administrator must be careful
+ that the amount of memory usable for all allocations
+ is not too small.
+
mpu401= [HW,OSS]
Format: <io>,<irq>
[HW] Make the MicroTouch USB driver use raw coordinates
('y', default) or cooked coordinates ('n')
+ mtrr_chunk_size=nn[KMG] [X86]
+ used for mtrr cleanup. It is largest continous chunk
+ that could hold holes aka. UC entries.
+
+ mtrr_gran_size=nn[KMG] [X86]
+ Used for mtrr cleanup. It is granularity of mtrr block.
+ Default is 1.
+ Large value could prevent small alignment from
+ using up MTRRs.
+
+ mtrr_spare_reg_nr=n [X86]
+ Format: <integer>
+ Range: 0,7 : spare reg number
+ Default : 1
+ Used for mtrr cleanup. It is spare mtrr entries number.
+ Set to 2 or more if your graphical card needs more.
+
n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
NCR_D700= [HW,SCSI]
0 - turn nmi_watchdog off
1 - use the IO-APIC timer for the NMI watchdog
2 - use the local APIC for the NMI watchdog using
- a performance counter. Note: This will use one performance
- counter and the local APIC's performance vector.
- When panic is specified panic when an NMI watchdog timeout occurs.
- This is useful when you use a panic=... timeout and need the box
- quickly up again.
+ a performance counter. Note: This will use one
+ performance counter and the local APIC's performance
+ vector.
+ When panic is specified, panic when an NMI watchdog
+ timeout occurs.
+ This is useful when you use a panic=... timeout and
+ need the box quickly up again.
Instead of 1 and 2 it is possible to use the following
symbolic names: lapic and ioapic
Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
emulation library even if a 387 maths coprocessor
is present.
+ no_console_suspend
+ [HW] Never suspend the console
+ Disable suspending of consoles during suspend and
+ hibernate operations. Once disabled, debugging
+ messages can reach various consoles while the rest
+ of the system is being put to sleep (ie, while
+ debugging driver suspend/resume hooks). This may
+ not work reliably with all consoles, but is known
+ to work with serial and VGA consoles.
+
noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
caches in the slab allocator. Saves per-node memory,
but will impact performance.
nocache [ARM]
+ noclflush [BUGS=X86] Don't use the CLFLUSH instruction
+
nodelayacct [KNL] Disable per-task delay accounting
nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
register save and restore. The kernel will only save
legacy floating-point registers on task switch.
- noclflush [BUGS=X86] Don't use the CLFLUSH instruction
-
nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or
wfi(ARM) instruction doesn't work correctly and not to
use it. This is also useful when using JTAG debugger.
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
- nox2apic [X86-64,APIC] Do not enable x2APIC mode.
-
- x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
- default x2apic cluster mode on platforms
- supporting x2apic.
-
noltlbs [PPC] Do not use large page/tlb entries for kernel
lowmem mapping on PPC40x.
nomfgpt [X86-32] Disable Multi-Function General Purpose
Timer usage (for AMD Geode machines).
+ norandmaps Don't use address space randomization. Equivalent to
+ echo 0 > /proc/sys/kernel/randomize_va_space
+
noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops
noreplace-smp [X86-32,SMP] Don't replace SMP instructions
purges which is reported from either PAL_VM_SUMMARY or
SAL PALO.
+ nr_uarts= [SERIAL] maximum number of UARTs to be registered.
+
numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
one of ['zone', 'node', 'default'] can be specified
This can be set from sysctl after boot.
See Documentation/sysctl/vm.txt for details.
- nr_uarts= [SERIAL] maximum number of UARTs to be registered.
-
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
See Documentation/debugging-via-ohci1394.txt for more
info.
printk.time= Show timing data prefixed to each printk message line
Format: <bool> (1/Y/y=enable, 0/N/n=disable)
+ processor.max_cstate= [HW,ACPI]
+ Limit processor to maximum C-state
+ max_cstate=9 overrides any DMI blacklist limit.
+
+ processor.nocst [HW,ACPI]
+ Ignore the _CST method to determine C-states,
+ instead using the legacy FADT method
+
profile= [KNL] Enable kernel profiling via /proc/profile
Format: [schedule,]<number>
Param: "schedule" - profile schedule points.
Requires CONFIG_SCHEDSTATS
Param: "kvm" - profile VM exits.
- processor.max_cstate= [HW,ACPI]
- Limit processor to maximum C-state
- max_cstate=9 overrides any DMI blacklist limit.
-
- processor.nocst [HW,ACPI]
- Ignore the _CST method to determine C-states,
- instead using the legacy FADT method
-
prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
before loading.
See Documentation/blockdev/ramdisk.txt.
allowing boot to proceed. none ignores them, expecting
user space to do the scan.
- selinux [SELINUX] Disable or enable SELinux at boot time.
+ security= [SECURITY] Choose a security module to enable at boot.
+ If this boot parameter is not specified, only the first
+ security module asking for security registration will be
+ loaded. An invalid security module name will be treated
+ as if no module has been chosen.
+
+ selinux= [SELINUX] Disable or enable SELinux at boot time.
Format: { "0" | "1" }
See security/selinux/Kconfig help text.
0 -- disable.
medium is write-protected).
Example: quirks=0419:aaf5:rl,0421:0433:rc
- add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in
- kernel's map of available physical RAM.
-
vdso= [X86-32,SH,x86-64]
vdso=2: enable compat VDSO (default with COMPAT_VDSO)
vdso=1: enable VDSO (default)
vmpoff= [KNL,S390] Perform z/VM CP command after power off.
Format: <command>
+ vt.default_blu= [VT]
+ Format: <blue0>,<blue1>,<blue2>,...,<blue15>
+ Change the default blue palette of the console.
+ This is a 16-member array composed of values
+ ranging from 0-255.
+
+ vt.default_grn= [VT]
+ Format: <green0>,<green1>,<green2>,...,<green15>
+ Change the default green palette of the console.
+ This is a 16-member array composed of values
+ ranging from 0-255.
+
+ vt.default_red= [VT]
+ Format: <red0>,<red1>,<red2>,...,<red15>
+ Change the default red palette of the console.
+ This is a 16-member array composed of values
+ ranging from 0-255.
+
+ vt.default_utf8=
+ [VT]
+ Format=<0|1>
+ Set system-wide default UTF-8 mode for all tty's.
+ Default is 1, i.e. UTF-8 mode is enabled for all
+ newly opened terminals.
+
waveartist= [HW,OSS]
Format: <io>,<irq>,<dma>,<dma2>
wdt= [WDT] Watchdog
See Documentation/watchdog/wdt.txt.
+ x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
+ default x2apic cluster mode on platforms
+ supporting x2apic.
+
xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
xd_geo= See header of drivers/block/xd.c.
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
- norandmaps Don't use address space randomization. Equivalent to
- echo 0 > /proc/sys/kernel/randomize_va_space
-
______________________________________________________________________
TODO:
is single-stepped, Kprobe calls kp->post_handler. If a fault
occurs during execution of kp->pre_handler or kp->post_handler,
or during single-stepping of the probed instruction, Kprobes calls
-kp->fault_handler. Any or all handlers can be NULL.
+kp->fault_handler. Any or all handlers can be NULL. If kp->flags
+is set KPROBE_FLAG_DISABLED, that kp will be registered but disabled,
+so, it's handlers aren't hit until calling enable_kprobe(kp).
NOTE:
1. With the introduction of the "symbol_name" field to struct kprobe,
incorrect probes. However, other probes in the array are
unregistered correctly.
+4.7 disable_*probe
+
+#include <linux/kprobes.h>
+int disable_kprobe(struct kprobe *kp);
+int disable_kretprobe(struct kretprobe *rp);
+int disable_jprobe(struct jprobe *jp);
+
+Temporarily disables the specified *probe. You can enable it again by using
+enable_*probe(). You must specify the probe which has been registered.
+
+4.8 enable_*probe
+
+#include <linux/kprobes.h>
+int enable_kprobe(struct kprobe *kp);
+int enable_kretprobe(struct kretprobe *rp);
+int enable_jprobe(struct jprobe *jp);
+
+Enables *probe which has been disabled by disable_*probe(). You must specify
+the probe which has been registered.
+
5. Kprobes Features and Limitations
Kprobes allows multiple probes at the same address. Currently,
is also specified. Following columns show probe status. If the probe is on
a virtual address that is no longer valid (module init sections, module
virtual addresses that correspond to modules that've been unloaded),
-such probes are marked with [GONE].
+such probes are marked with [GONE]. If the probe is temporarily disabled,
+such probes are marked with [DISABLED].
-/debug/kprobes/enabled: Turn kprobes ON/OFF
+/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
-Provides a knob to globally turn registered kprobes ON or OFF. By default,
-all kprobes are enabled. By echoing "0" to this file, all registered probes
-will be disarmed, till such time a "1" is echoed to this file.
+Provides a knob to globally and forcibly turn registered kprobes ON or OFF.
+By default, all kprobes are enabled. By echoing "0" to this file, all
+registered probes will be disarmed, till such time a "1" is echoed to this
+file. Note that this knob just disarms and arms all kprobes and doesn't
+change each probe's disabling state. This means that disabled kprobes (marked
+[DISABLED]) will be not enabled if you turn ON all kprobes by this knob.
- reg : should specify localbus chip select and size used for the chip.
- fsl,upm-addr-offset : UPM pattern offset for the address latch.
- fsl,upm-cmd-offset : UPM pattern offset for the command latch.
-- gpios : may specify optional GPIO connected to the Ready-Not-Busy pin.
-Example:
+Optional properties:
+- fsl,upm-wait-flags : add chip-dependent short delays after running the
+ UPM pattern (0x1), after writing a data byte (0x2) or after
+ writing out a buffer (0x4).
+- fsl,upm-addr-line-cs-offsets : address offsets for multi-chip support.
+ The corresponding address lines are used to select the chip.
+- gpios : may specify optional GPIOs connected to the Ready-Not-Busy pins
+ (R/B#). For multi-chip devices, "n" GPIO definitions are required
+ according to the number of chips.
+- chip-delay : chip dependent delay for transfering data from array to
+ read registers (tR). Required if property "gpios" is not used
+ (R/B# pins not connected).
+
+Examples:
upm@1,0 {
compatible = "fsl,upm-nand";
};
};
};
+
+upm@3,0 {
+ #address-cells = <0>;
+ #size-cells = <0>;
+ compatible = "tqc,tqm8548-upm-nand", "fsl,upm-nand";
+ reg = <3 0x0 0x800>;
+ fsl,upm-addr-offset = <0x10>;
+ fsl,upm-cmd-offset = <0x08>;
+ /* Multi-chip NAND device */
+ fsl,upm-addr-line-cs-offsets = <0x0 0x200>;
+ fsl,upm-wait-flags = <0x5>;
+ chip-delay = <25>; // in micro-seconds
+
+ nand@0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ partition@0 {
+ label = "fs";
+ reg = <0x00000000 0x10000000>;
+ };
+ };
+};
-LED connected to GPIO
+LEDs connected to GPIO lines
Required properties:
-- compatible : should be "gpio-led".
-- label : (optional) the label for this LED. If omitted, the label is
+- compatible : should be "gpio-leds".
+
+Each LED is represented as a sub-node of the gpio-leds device. Each
+node's name represents the name of the corresponding LED.
+
+LED sub-node properties:
+- gpios : Should specify the LED's GPIO, see "Specifying GPIO information
+ for devices" in Documentation/powerpc/booting-without-of.txt. Active
+ low LEDs should be indicated using flags in the GPIO specifier.
+- label : (optional) The label for this LED. If omitted, the label is
taken from the node name (excluding the unit address).
-- gpios : should specify LED GPIO.
+- linux,default-trigger : (optional) This parameter, if present, is a
+ string defining the trigger assigned to the LED. Current triggers are:
+ "backlight" - LED will act as a back-light, controlled by the framebuffer
+ system
+ "default-on" - LED will turn on
+ "heartbeat" - LED "double" flashes at a load average based rate
+ "ide-disk"&nb