diff options
Diffstat (limited to 'Documentation')
26 files changed, 952 insertions, 505 deletions
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 1ae4dc0fd856..f8fe882e33dc 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -59,6 +59,9 @@ !Iinclude/linux/hrtimer.h !Ekernel/hrtimer.c </sect1> + <sect1><title>Workqueues and Kevents</title> +!Ekernel/workqueue.c + </sect1> <sect1><title>Internal Functions</title> !Ikernel/exit.c !Ikernel/signal.c @@ -300,7 +303,7 @@ X!Ekernel/module.c </sect1> <sect1><title>Resources Management</title> -!Ekernel/resource.c +!Ikernel/resource.c </sect1> <sect1><title>MTRR Handling</title> @@ -312,9 +315,7 @@ X!Ekernel/module.c !Edrivers/pci/pci-driver.c !Edrivers/pci/remove.c !Edrivers/pci/pci-acpi.c -<!-- kerneldoc does not understand __devinit -X!Edrivers/pci/search.c - --> +!Edrivers/pci/search.c !Edrivers/pci/msi.c !Edrivers/pci/bus.c <!-- FIXME: Removed for now since no structured comments in source diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index c2c85bcb3d43..2cd7f02ffd0b 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -10,7 +10,9 @@ kernel, the process can sometimes be daunting if you're not familiar with "the system." This text is a collection of suggestions which can greatly increase the chances of your change being accepted. -If you are submitting a driver, also read Documentation/SubmittingDrivers. +Read Documentation/SubmitChecklist for a list of items to check +before submitting code. If you are submitting a driver, also read +Documentation/SubmittingDrivers. @@ -74,9 +76,6 @@ There are a number of scripts which can aid in this: Quilt: http://savannah.nongnu.org/projects/quilt -Randy Dunlap's patch scripts: -http://www.xenotime.net/linux/scripts/patching-scripts-002.tar.gz - Andrew Morton's patch scripts: http://www.zip.com.au/~akpm/linux/patches/ Instead of these scripts, quilt is the recommended patch management @@ -484,7 +483,7 @@ Greg Kroah-Hartman "How to piss off a kernel subsystem maintainer". <http://www.kroah.com/log/2005/10/19/> <http://www.kroah.com/log/2006/01/11/> -NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people!. +NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people! <http://marc.theaimsgroup.com/?l=linux-kernel&m=112112749912944&w=2> Kernel Documentation/CodingStyle @@ -493,4 +492,3 @@ Kernel Documentation/CodingStyle Linus Torvald's mail on the canonical patch format: <http://lkml.org/lkml/2005/4/7/183> -- -Last updated on 17 Nov 2005. diff --git a/Documentation/accounting/delay-accounting.txt b/Documentation/accounting/delay-accounting.txt index be215e58423b..1443cd71d263 100644 --- a/Documentation/accounting/delay-accounting.txt +++ b/Documentation/accounting/delay-accounting.txt @@ -64,11 +64,13 @@ Compile the kernel with CONFIG_TASK_DELAY_ACCT=y CONFIG_TASKSTATS=y -Enable the accounting at boot time by adding -the following to the kernel boot options - delayacct +Delay accounting is enabled by default at boot up. +To disable, add + nodelayacct +to the kernel boot options. The rest of the instructions +below assume this has not been done. -and after the system has booted up, use a utility +After the system has booted up, use a utility similar to getdelays.c to access the delays seen by a given task or a task group (tgid). The utility also allows a given command to be diff --git a/Documentation/connector/ucon.c b/Documentation/connector/ucon.c new file mode 100644 index 000000000000..d738cde2a8d5 --- /dev/null +++ b/Documentation/connector/ucon.c @@ -0,0 +1,206 @@ +/* + * ucon.c + * + * Copyright (c) 2004+ Evgeniy Polyakov <johnpol@2ka.mipt.ru> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <asm/types.h> + +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/poll.h> + +#include <linux/netlink.h> +#include <linux/rtnetlink.h> + +#include <arpa/inet.h> + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <time.h> + +#include <linux/connector.h> + +#define DEBUG +#define NETLINK_CONNECTOR 11 + +#ifdef DEBUG +#define ulog(f, a...) fprintf(stdout, f, ##a) +#else +#define ulog(f, a...) do {} while (0) +#endif + +static int need_exit; +static __u32 seq; + +static int netlink_send(int s, struct cn_msg *msg) +{ + struct nlmsghdr *nlh; + unsigned int size; + int err; + char buf[128]; + struct cn_msg *m; + + size = NLMSG_SPACE(sizeof(struct cn_msg) + msg->len); + + nlh = (struct nlmsghdr *)buf; + nlh->nlmsg_seq = seq++; + nlh->nlmsg_pid = getpid(); + nlh->nlmsg_type = NLMSG_DONE; + nlh->nlmsg_len = NLMSG_LENGTH(size - sizeof(*nlh)); + nlh->nlmsg_flags = 0; + + m = NLMSG_DATA(nlh); +#if 0 + ulog("%s: [%08x.%08x] len=%u, seq=%u, ack=%u.\n", + __func__, msg->id.idx, msg->id.val, msg->len, msg->seq, msg->ack); +#endif + memcpy(m, msg, sizeof(*m) + msg->len); + + err = send(s, nlh, size, 0); + if (err == -1) + ulog("Failed to send: %s [%d].\n", + strerror(errno), errno); + + return err; +} + +int main(int argc, char *argv[]) +{ + int s; + char buf[1024]; + int len; + struct nlmsghdr *reply; + struct sockaddr_nl l_local; + struct cn_msg *data; + FILE *out; + time_t tm; + struct pollfd pfd; + + if (argc < 2) + out = stdout; + else { + out = fopen(argv[1], "a+"); + if (!out) { + ulog("Unable to open %s for writing: %s\n", + argv[1], strerror(errno)); + out = stdout; + } + } + + memset(buf, 0, sizeof(buf)); + + s = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR); + if (s == -1) { + perror("socket"); + return -1; + } + + l_local.nl_family = AF_NETLINK; + l_local.nl_groups = 0x123; /* bitmask of requested groups */ + l_local.nl_pid = 0; + + if (bind(s, (struct sockaddr *)&l_local, sizeof(struct sockaddr_nl)) == -1) { + perror("bind"); + close(s); + return -1; + } + +#if 0 + { + int on = 0x57; /* Additional group number */ + setsockopt(s, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &on, sizeof(on)); + } +#endif + if (0) { + int i, j; + + memset(buf, 0, sizeof(buf)); + + data = (struct cn_msg *)buf; + + data->id.idx = 0x123; + data->id.val = 0x456; + data->seq = seq++; + data->ack = 0; + data->len = 0; + + for (j=0; j<10; ++j) { + for (i=0; i<1000; ++i) { + len = netlink_send(s, data); + } + + ulog("%d messages have been sent to %08x.%08x.\n", i, data->id.idx, data->id.val); + } + + return 0; + } + + + pfd.fd = s; + + while (!need_exit) { + pfd.events = POLLIN; + pfd.revents = 0; + switch (poll(&pfd, 1, -1)) { + case 0: + need_exit = 1; + break; + case -1: + if (errno != EINTR) { + need_exit = 1; + break; + } + continue; + } + if (need_exit) + break; + + memset(buf, 0, sizeof(buf)); + len = recv(s, buf, sizeof(buf), 0); + if (len == -1) { + perror("recv buf"); + close(s); + return -1; + } + reply = (struct nlmsghdr *)buf; + + switch (reply->nlmsg_type) { + case NLMSG_ERROR: + fprintf(out, "Error message received.\n"); + fflush(out); + break; + case NLMSG_DONE: + data = (struct cn_msg *)NLMSG_DATA(reply); + + time(&tm); + fprintf(out, "%.24s : [%x.%x] [%08u.%08u].\n", + ctime(&tm), data->id.idx, data->id.val, data->seq, data->ack); + fflush(out); + break; + default: + break; + } + } + + close(s); + return 0; +} diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index 7fedc00c3d30..555c8cf3650a 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -153,10 +153,13 @@ scaling_governor, and by "echoing" the name of another that some governors won't load - they only work on some specific architectures or processors. -scaling_min_freq and +scaling_min_freq and scaling_max_freq show the current "policy limits" (in kHz). By echoing new values into these files, you can change these limits. + NOTE: when setting a policy you need to + first set scaling_max_freq, then + scaling_min_freq. If you have selected the "userspace" governor which allows you to diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index 1bcf69996c9d..bc107cb157a8 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt @@ -251,16 +251,24 @@ A: This is what you would need in your kernel code to receive notifications. return NOTIFY_OK; } - static struct notifier_block foobar_cpu_notifer = + static struct notifier_block __cpuinitdata foobar_cpu_notifer = { .notifier_call = foobar_cpu_callback, }; +You need to call register_cpu_notifier() from your init function. +Init functions could be of two types: +1. early init (init function called when only the boot processor is online). +2. late init (init function called _after_ all the CPUs are online). -In your init function, +For the first case, you should add the following to your init function register_cpu_notifier(&foobar_cpu_notifier); +For the second case, you should add the following to your init function + + register_hotcpu_notifier(&foobar_cpu_notifier); + You can fail PREPARE notifiers if something doesn't work to prepare resources. This will stop the activity and send a following CANCELED event back. diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt index 159e2a0c3e80..76b44290c154 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cpusets.txt @@ -217,6 +217,12 @@ exclusive cpuset. Also, the use of a Linux virtual file system (vfs) to represent the cpuset hierarchy provides for a familiar permission and name space for cpusets, with a minimum of additional kernel code. +The cpus file in the root (top_cpuset) cpuset is read-only. +It automatically tracks the value of cpu_online_map, using a CPU +hotplug notifier. If and when memory nodes can be hotplugged, +we expect to make the mems file in the root cpuset read-only +as well, and have it track the value of node_online_map. + 1.4 What are exclusive cpusets ? -------------------------------- diff --git a/Documentation/devices.txt b/Documentation/devices.txt index 4aaf68fafebe..66c725f530f3 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt @@ -2565,10 +2565,10 @@ Your cooperation is appreciated. 243 = /dev/usb/dabusb3 Fourth dabusb device 180 block USB block devices - 0 = /dev/uba First USB block device - 8 = /dev/ubb Second USB block device - 16 = /dev/ubc Thrid USB block device - ... + 0 = /dev/uba First USB block device + 8 = /dev/ubb Second USB block device + 16 = /dev/ubc Third USB block device + ... 181 char Conrad Electronic parallel port radio clocks 0 = /dev/pcfclock0 First Conrad radio clock diff --git a/Documentation/fb/imacfb.txt b/Documentation/fb/imacfb.txt new file mode 100644 index 000000000000..759028545a7e --- /dev/null +++ b/Documentation/fb/imacfb.txt @@ -0,0 +1,31 @@ + +What is imacfb? +=============== + +This is a generic EFI platform driver for Intel based Apple computers. +Imacfb is only for EFI booted Intel Macs. + +Supported Hardware +================== + +iMac 17"/20" +Macbook +Macbook Pro 15"/17" +MacMini + +How to use it? +============== + +Imacfb does not have any kind of autodetection of your machine. +You have to add the fillowing kernel parameters in your elilo.conf: + Macbook : + video=imacfb:macbook + MacMini : + video=imacfb:mini + Macbook Pro 15", iMac 17" : + video=imacfb:i17 + Macbook Pro 17", iMac 20" : + video=imacfb:i20 + +-- +Edgar Hucek <gimli@dark-green.com> diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX index 66fdc0744fe0..16dec61d7671 100644 --- a/Documentation/filesystems/00-INDEX +++ b/Documentation/filesystems/00-INDEX @@ -62,8 +62,8 @@ ramfs-rootfs-initramfs.txt - info on the 'in memory' filesystems ramfs, rootfs and initramfs. reiser4.txt - info on the Reiser4 filesystem based on dancing tree algorithms. -relayfs.txt - - info on relayfs, for efficient streaming from kernel to user space. +relay.txt + - info on relay, for efficient streaming from kernel to user space. romfs.txt - description of the ROMFS filesystem. smbfs.txt diff --git a/Documentation/filesystems/relay.txt b/Documentation/filesystems/relay.txt new file mode 100644 index 000000000000..d6788dae0349 --- /dev/null +++ b/Documentation/filesystems/relay.txt @@ -0,0 +1,479 @@ +relay interface (formerly relayfs) +================================== + +The relay interface provides a means for kernel applications to +efficiently log and transfer large quantities of data from the kernel +to userspace via user-defined 'relay channels'. + +A 'relay channel' is a kernel->user data relay mechanism implemented +as a set of per-cpu kernel buffers ('channel buffers'), each +represented as a regular file ('relay file') in user space. Kernel +clients write into the channel buffers using efficient write +functions; these automatically log into the current cpu's channel +buffer. User space applications mmap() or read() from the relay files +and retrieve the data as it becomes available. The relay files +themselves are files created in a host filesystem, e.g. debugfs, and +are associated with the channel buffers using the API described below. + +The format of the data logged into the channel buffers is completely +up to the kernel client; the relay interface does however provide +hooks which allow kernel clients to impose some structure on the +buffer data. The relay interface doesn't implement any form of data +filtering - this also is left to the kernel client. The purpose is to +keep things as simple as possible. + +This document provides an overview of the relay interface API. The +details of the function parameters are documented along with the +functions in the relay interface code - please see that for details. + +Semantics +========= + +Each relay channel has one buffer per CPU, each buffer has one or more +sub-buffers. Messages are written to the first sub-buffer until it is +too full to contain a new message, in which case it it is written to +the next (if available). Messages are never split across sub-buffers. +At this point, userspace can be notified so it empties the first +sub-buffer, while the kernel continues writing to the next. + +When notified that a sub-buffer is full, the kernel knows how many +bytes of it are padding i.e. unused space occurring because a complete +message couldn't fit into a sub-buffer. Userspace can use this +knowledge to copy only valid data. + +After copying it, userspace can notify the kernel that a sub-buffer +has been consumed. + +A relay channel can operate in a mode where it will overwrite data not +yet collected by userspace, and not wait for it to be consumed. + +The relay channel itself does not provide for communication of such +data between userspace and kernel, allowing the kernel side to remain +simple and not impose a single interface on userspace. It does +provide a set of examples and a separate helper though, described +below. + +The read() interface both removes padding and internally consumes the +read sub-buffers; thus in cases where read(2) is being used to drain +the channel buffers, special-purpose communication between kernel and +user isn't necessary for basic operation. + +One of the major goals of the relay interface is to provide a low +overhead mechanism for conveying kernel data to userspace. While the +read() interface is easy to use, it's not as efficient as the mmap() +approach; the example code attempts to make the tradeoff between the +two approaches as small as possible. + +klog and relay-apps example code +================================ + +The relay interface itself is ready to use, but to make things easier, +a couple simple utility functions and a set of examples are provided. + +The relay-apps example tarball, available on the relay sourceforge +site, contains a set of self-contained examples, each consisting of a +pair of .c files containing boilerplate code for each of the user and +kernel sides of a relay application. When combined these two sets of +boilerplate code provide glue to easily stream data to disk, without +having to bother with mundane housekeeping chores. + +The 'klog debugging functions' patch (klog.patch in the relay-apps +tarball) provides a couple of high-level logging functions to the +kernel which allow writing formatted text or raw data to a channel, +regardless of whether a channel to write into exists or not, or even +whether the relay interface is compiled into the kernel or not. These +functions allow you to put unconditional 'trace' statements anywhere +in the kernel or kernel modules; only when there is a 'klog handler' +registered will data actually be logged (see the klog and kleak +examples for details). + +It is of course possible to use the relay interface from scratch, +i.e. without using any of the relay-apps example code or klog, but +you'll have to implement communication between userspace and kernel, +allowing both to convey the state of buffers (full, empty, amount of +padding). The read() interface both removes padding and internally +consumes the read sub-buffers; thus in cases where read(2) is being +used to drain the channel buffers, special-purpose communication +between kernel and user isn't necessary for basic operation. Things +such as buffer-full conditions would still need to be communicated via +some channel though. + +klog and the relay-apps examples can be found in the relay-apps +tarball on http://relayfs.sourceforge.net + +The relay interface user space API +================================== + +The relay interface implements basic file operations for user space +access to relay channel buffer data. Here are the file operations +that are available and some comments regarding their behavior: + +open() enables user to open an _existing_ channel buffer. + +mmap() results in channel buffer being mapped into the caller's + memory space. Note that you can't do a partial mmap - you + must map the entire file, which is NRBUF * SUBBUFSIZE. + +read() read the contents of a channel buffer. The bytes read are + 'consumed' by the reader, i.e. they won't be available + again to subsequent reads. If the channel is being used + in no-overwrite mode (the default), it can be read at any + time even if there's an active kernel writer. If the + channel is being used in overwrite mode and there are + active channel writers, results may be unpredictable - + users should make sure that all logging to the channel has + ended before using read() with overwrite mode. Sub-buffer + padding is automatically removed and will not be seen by + the reader. + +sendfile() transfer data from a channel buffer to an output file + descriptor. Sub-buffer padding is automatically removed + and will not be seen by the reader. + +poll() POLLIN/POLLRDNORM/POLLERR supported. User applications are + notified when sub-buffer boundaries are crossed. + +close() decrements the channel buffer's refcount. When the refcount + reaches 0, i.e. when no process or kernel client has the + buffer open, the channel buffer is freed. + +In order for a user application to make use of relay files, the +host filesystem must be mounted. For example, + + mount -t debugfs debugfs /debug + +NOTE: the host filesystem doesn't need to be mounted for kernel + clients to create or use channels - it only needs to be + mounted when user space applications need access to the buffer + data. + + +The relay interface kernel API +============================== + +Here's a summary of the API the relay interface provides to in-kernel clients: + +TBD(curr. line MT:/API/) + channel management functions: + + relay_open(base_filename, parent, subbuf_size, n_subbufs, + callbacks) + relay_close(chan) + relay_flush(chan) + relay_reset(chan) + + channel management typically called on instigation of userspace: + + relay_subbufs_consumed(chan, cpu, subbufs_consumed) + + write functions: + + relay_write(chan, data, length) + __relay_write(chan, data, length) + relay_reserve(chan, length) + + callbacks: + + subbuf_start(buf, subbuf, prev_subbuf, prev_padding) + buf_mapped(buf, filp) + buf_unmapped(buf, filp) + create_buf_file(filename, parent, mode, buf, is_global) + remove_buf_file(dentry) + + helper functions: + + relay_buf_full(buf) + subbuf_start_reserve(buf, length) + + +Creating a channel +------------------ + +relay_open() is used to create a channel, along with its per-cpu +channel buffers. Each channel buffer will have an associated file +created for it in the host filesystem, which can be and mmapped or +read from in user space. The files are named basename0...basenameN-1 +where N is the number of online cpus, and by default will be created +in the root of the filesystem (if the parent param is NULL). If you +want a directory structure to contain your relay files, you should +create it using the host filesystem's directory creation function, +e.g. debugfs_create_dir(), and pass the parent directory to +relay_open(). Users are responsible for cleaning up any directory +structure they create, when the channel is closed - again the host +filesystem's directory removal functions should be used for that, +e.g. debugfs_remove(). + +In order for a channel to be created and the host filesystem's files +associated with its channel buffers, the user must provide definitions +for two callback functions, create_buf_file() and remove_buf_file(). +create_buf_file() is called once for each per-cpu buffer from +relay_open() and allows the user to create the file which will be used +to represent the corresponding channel buffer. The callback should +return the dentry of the file created to represent the channel buffer. +remove_buf_file() must also be defined; it's responsible for deleting +the file(s) created in create_buf_file() and is called during +relay_close(). + +Here are some typical definitions for these callbacks, in this case +using debugfs: + +/* + * create_buf_file() callback. Creates relay file in debugfs. + */ +static struct dentry *create_buf_file_handler(const char *filename, + struct dentry *parent, + int mode, + struct rchan_buf *buf, + int *is_global) +{ + return debugfs_create_file(filename, mode, parent, buf, + &relay_file_operations); +} + +/* + * remove_buf_file() callback. Removes relay file from debugfs. + */ +static int remove_buf_file_handler(struct dentry *dentry) +{ + debugfs_remove(dentry); + + return 0; +} + +/* + * relay interface callbacks + */ +static struct rchan_callbacks relay_callbacks = +{ + .create_buf_file = create_buf_file_handler, + .remove_buf_file = remove_buf_file_handler, +}; + +And an example relay_open() invocation using them: + + chan = relay_open("cpu", NULL, SUBBUF_SIZE, N_SUBBUFS, &relay_callbacks); + +If the create_buf_file() callback fails, or isn't defined, channel +creation and thus relay_open() will fail. + +The total size of each per-cpu buffer is calculated by multiplying the +number of sub-buffers by the sub-buffer size passed into relay_open(). +The idea behind sub-buffers is that they're basically an extension of +double-buffering to N buffers, and they also allow applications to +easily implement random-access-on-buffer-boundary schemes, which can +be important for some high-volume applications. The number and size +of sub-buffers is completely dependent on the application and even for +the same application, different conditions will warrant different +values for these parameters at different times. Typically, the right +values to use are best decided after some experimentation; in general, +though, it's safe to assume that having only 1 sub-buffer is a bad +idea - you're guaranteed to either overwrite data or lose events +depending on the channel mode being used. + +The create_buf_file() implementation can also be defined in such a way +as to allow the creation of a single 'global' buffer instead of the +default per-cpu set. This can be useful for applications interested +mainly in seeing the relative ordering of system-wide events without +the need to bother with saving explicit timestamps for the purpose of +merging/sorting per-cpu files in a postprocessing step. + +To have relay_open() create a global buffer, the create_buf_file() +implementation should set the value of the is_global outparam to a +non-zero value in addition to creating the file that will be used to +represent the single buffer. In the case of a global buffer, +create_buf_file() and remove_buf_file() will be called only once. The +normal channel-writing functions, e.g. relay_write(), can still be +used - writes from any cpu will transparently end up in the global +buffer - but since it is a global buffer, callers should make sure +they use the proper locking for such a buffer, either by wrapping +writes in a spinlock, or by copying a write function from relay.h and +creating a local version that internally does the proper locking. + +Channel 'modes' +--------------- + +relay channels can be used in either of two modes - 'overwrite' or +'no-overwrite'. The mode is entirely determined by the implementation +of the subbuf_start() callback, as described below. The default if no +subbuf_start() callback is defined is 'no-overwrite' mode. If the +default mode suits your needs, and you plan to use the read() +interface to retrieve channel data, you can ignore the details of this +section, as it pertains mainly to mmap() implementations. + +In 'overwrite' mode, also known as 'flight recorder' mode, writes +continuously cycle around the buffer and will never fail, but will +unconditionally overwrite old data regardless of whether it's actually +been consumed. In no-overwrite mode, writes will fail, i.e. data will +be lost, if the number of unconsumed sub-buffers equals the total +number of sub-buffers in the channel. It should be clear that if +there is no consumer or if the consumer can't consume sub-buffers fast +enough, data will be lost in either case; the only difference is +whether data is lost from the beginning or the end of a buffer. + +As explained above, a relay channel is made of up one or more +per-cpu channel buffers, each implemented as a circular buffer +subdivided into one or more sub-buffers. Messages are written into +the current sub-buffer of the channel's current per-cpu buffer via the +write functions described below. Whenever a message can't fit into +the current sub-buffer, because there's no room left for it, the +client is notified via the subbuf_start() callback that a switch to a +new sub-buffer is about to occur. The client uses this callback to 1) +initialize the next sub-buffer if appropriate 2) finalize the previous +sub-buffer if appropriate and 3) return a boolean value indicating +whether or not to actually move on to the next sub-buffer. + +To implement 'no-overwrite' mode, the userspace client would provide +an implementation of the subbuf_start() callback something like the +following: + +static int subbuf_start(struct rchan_buf *buf, + void *subbuf, + void *prev_subbuf, + unsigned int prev_padding) +{ + if (prev_subbuf) + *((unsigned *)prev_subbuf) = prev_padding; + + if (relay_buf_full(buf)) + return 0; + + subbuf_start_reserve(buf, sizeof(unsigned int)); + + return 1; +} + +If the current buffer is full, i.e. all sub-buffers remain unconsumed, +the callback returns 0 to indicate that the buffer switch should not +occur yet, i.e. until the consumer has had a chance to read the +current set of ready sub-buffers. For the relay_buf_full() function +to make sense, the consumer is reponsible for notifying the relay +interface when sub-buffers have been consumed via +relay_subbufs_consumed(). Any subsequent attempts to write into the +buffer will again invoke the subbuf_start() callback with the same +parameters; only when the consumer has consumed one or more of the +ready sub-buffers will relay_buf_full() return 0, in which case the +buffer switch can continue. + +The implementation of the subbuf_start() callback for 'overwrite' mode +would be very similar: + +static int subbuf_start(struct rchan_buf *buf, + void *subbuf, + void *prev_subbuf, + unsigned int prev_padding) +{ + if (prev_subbuf) + *((unsigned *)prev_subbuf) = prev_padding; + + subbuf_start_reserve(buf, sizeof(unsigned int)); + + return 1; +} + +In this case, the relay_buf_full() check is meaningless and the +callback always returns 1, causing the buffer switch to occur +unconditionally. It's also meaningless for the client to use the +relay_subbufs_consumed() function in this mode, as it's never +consulted. + +The default subbuf_start() implementation, used if the client doesn't +define any callbacks, or doesn't define the subbuf_start() callback, +implements the simplest possible 'no-overwrite' mode, i.e. it does +nothing but return 0. + +Header information can be reserved at the beginning of each sub-buffer +by calling the subbuf_start_reserve() helper function from within the +subbuf_start() callback. This reserved area can be used to store +whatever information the client wants. In the example above, room is +reserved in each sub-buffer to store the padding count for that +sub-buffer. This is filled in for the previous sub-buffer in the +subbuf_start() implementation; the padding value for the previous +sub-buffer is passed into the subbuf_start() callback along with a +pointer to the previous sub-buffer, since the padding value isn't +known until a sub-buffer is filled. The subbuf_start() callback is +also called for the first sub-buffer when the channel is opened, to +give the client a chance to reserve space in it. In this case the +previous sub-buffer pointer passed into the callback will be NULL, so +the client should check the value of the prev_subbuf pointer before +writing into the previous sub-buffer. + +Writing to a channel +-------------------- + +Kernel clients write data into the current cpu's channel buffer using +relay_write() or __relay_write(). relay_write() is the main logging +function - it uses local_irqsave() to protect the buffer and should be +used if you might be logging from interrupt context. If you know +you'll never be logging from interrupt context, you can use +__relay_write(), which only disables preemption. These functions +don't return a value, so you can't determine whether or not they +failed - the assumption is that you wouldn't want to check a return +value in the fast logging path anyway, and that they'll always succeed +unless the buffer is full and no-overwrite mode is being used, in +which case you can detect a failed write in the subbuf_start() +callback by calling the relay_buf_full() helper function. + +relay_reserve() is used to reserve a slot in a channel buffer which +can be written to later. This would typically be used in applications +that need to write directly into a channel buffer without having to +stage data in a temporary buffer beforehand. Because the actual write +may not happen immediately after the slot is reserved, applications +using relay_reserve() can keep a count of the number of bytes actually +written, either in space reserved in the sub-buffers themselves or as +a separate array. See the 'reserve' example in the relay-apps tarball +at http://relayfs.sourceforge.net for an example of how this can be +done. Because the write is under control of the client and is +separated from the reserve, relay_reserve() doesn't protect the buffer +at all - it's up to the client to provide the appropriate +synchronization when using relay_reserve(). + +Closing a channel +----------------- + +The client calls relay_close() when it's finished using the channel. +The channel and its associated buffers are destroyed when there are no +longer any references to any of the channel buffers. relay_flush() +forces a sub-buffer switch on all the channel buffers, and can be used +to finalize and process the last sub-buffers before the channel is +closed. + +Misc +---- + +Some applications may want to keep a channel around and re-use it +rather than open and close a new channel for each use. relay_reset() +can be used for this purpose - it resets a channel to its initial +state without reallocating channel buffer memory or destroying +existing mappings. It should however only be called when it's safe to +do so, i.e. when the channel isn't currently being written to. + +Finally, there are a couple of utility callbacks that can be used for +different purposes. buf_mapped() is called whenever a channel buffer +is mmapped from user space and buf_unmapped() is called when it's +unmapped. The client can use this notification to trigger actions +within the kernel application, such as enabling/disabling logging to +the channel. + + +Resources +========= + +For news, example code, mailing list, etc. see the relay interface homepage: + + http://relayfs.sourceforge.net + + +Credits +======= + +The ideas and specs for the relay interface came about as a result of +discussions on tracing involving the following: + +Michel Dagenais <michel.dagenais@polymtl.ca> +Richard Moore <richardj_moore@uk.ibm.com> +Bob Wisniewski <bob@watson.ibm.com> +Karim Yaghmour <karim@opersys.com> +Tom Zanussi <zanussi@us.ibm.com> + +Also thanks to Hubertus Franke for a lot of useful suggestions and bug +reports. diff --git a/Documentation/filesystems/relayfs.txt b/Documentation/filesystems/relayfs.txt deleted file mode 100644 index 5832377b7340..000000000000 --- a/Documentation/filesystems/relayfs.txt +++ /dev/null @@ -1,442 +0,0 @@ - -relayfs - a high-speed data relay filesystem -============================================ - -relayfs is a filesystem designed to provide an efficient mechanism for -tools and facilities to relay large and potentially sustained streams -of data from kernel space to user space. - -The main abstraction of relayfs is the 'channel'. A channel consists -of a set of per-cpu kernel buffers each represented by a file in the -relayfs filesystem. Kernel clients write into a channel using -efficient write functions which automatically log to the current cpu's -channel buffer. User space applications mmap() the per-cpu files and -retrieve the data as it becomes available. - -The format of the data logged into the channel buffers is completely -up to the relayfs client; relayfs does however provide hooks which -allow clients to impose some structure on the buffer data. Nor does -relayfs implement any form of data filtering - this also is left to -the client. The purpose is to keep relayfs as simple as possible. - -This document provides an overview of the relayfs API. The details of -the function parameters are documented along with the functions in the -filesystem code - please see that for details. - -Semantics -========= - -Each relayfs channel has one buffer per CPU, each buffer has one or -more sub-buffers. Messages are written to the first sub-buffer until -it is too full to contain a new message, in which case it it is -written to the next (if available). Messages are never split across -sub-buffers. At this point, userspace can be notified so it empties -the first sub-buffer, while the kernel continues writing to the next. - -When notified that a sub-buffer is full, the kernel knows how many -bytes of it are padding i.e. unused. Userspace can use this knowledge -to copy only valid data. - -After copying it, userspace can notify the kernel that a sub-buffer -has been consumed. - -relayfs can operate in a mode where it will overwrite data not yet -collected by userspace, and not wait for it to consume it. - -relayfs itself does not provide for communication of such data between -userspace and kernel, allowing the kernel side to remain simple and -not impose a single interface on userspace. It does provide a set of -examples and a separate helper though, described below. - -klog and relay-apps example code -================================ - -relayfs itself is ready to use, but to make things easier, a couple -simple utility functions and a set of examples are provided. - -The relay-apps example tarball, available on the relayfs sourceforge -site, contains a set of self-contained examples, each consisting of a -pair of .c files containing boilerplate code for each of the user and -kernel sides of a relayfs application; combined these two sets of -boilerplate code provide glue to easily stream data to disk, without -having to bother with mundane housekeeping chores. - -The 'klog debugging functions' patch (klog.patch in the relay-apps -tarball) provides a couple of high-level logging functions to the -kernel which allow writing formatted text or raw data to a channel, -regardless of whether a channel to write into exists or not, or -whether relayfs is compiled into the kernel or is configured as a -module. These functions allow you to put unconditional 'trace' -statements anywhere in the kernel or kernel modules; only when there -is a 'klog handler' registered will data actually be logged (see the -klog and kleak examples for details). - -It is of course possible to use relayfs from scratch i.e. without -using any of the relay-apps example code or klog, but you'll have to -implement communication between userspace and kernel, allowing both to -convey the state of buffers (full, empty, amount of padding). - -klog and the relay-apps examples can be found in the relay-apps -tarball on http://relayfs.sourceforge.net - - -The relayfs user space API -========================== - -relayfs implements basic file operations for user space access to -relayfs channel buffer data. Here are the file operations that are -available and some comments regarding their behavior: - -open() enables user to open an _existing_ buffer. - -mmap() results in channel buffer being mapped into the caller's - memory space. Note that you can't do a partial mmap - you must - map the entire file, which is NRBUF * SUBBUFSIZE. - -read() read the contents of a channel buffer. The bytes read are - 'consumed' by the reader i.e. they won't be available again - to subsequent reads. If the channel is being used in - no-overwrite mode (the default), it can be read at any time - even if there's an active kernel writer. If the channel is - being used in overwrite mode and there are active channel - writers, results may be unpredictable - users should make - sure that all logging to the channel has ended before using - read() with overwrite mode. - -poll() POLLIN/POLLRDNORM/POLLERR supported. User applications are - notified when sub-buffer boundaries are crossed. - -close() decrements the channel buffer's refcount. When the refcount - reaches 0 i.e. when no process or kernel client has the buffer - open, the channel buffer is freed. - - -In order for a user application to make use of relayfs files, the -relayfs filesystem must be mounted. For example, - - mount -t relayfs relayfs /mnt/relay - -NOTE: relayfs doesn't need to be mounted for kernel clients to create - or use channels - it only needs to be mounted when user space - applications need access to the buffer data. - - -The relayfs kernel API -====================== - -Here's a summary of the API relayfs provides to in-kernel clients: - - - channel management functions: - - relay_open(base_filename, parent, subbuf_size, n_subbufs, - callbacks) - relay_close(chan) - relay_flush(chan) - relay_reset(chan) - relayfs_create_dir(name, parent) - relayfs_remove_dir(dentry) - relayfs_create_file(name, parent, mode, fops, data) - relayfs_remove_file(dentry) - - channel management typically called on instigation of userspace: - - relay_subbufs_consumed(chan, cpu, subbufs_consumed) - - write functions: - - relay_write(chan, data, length) - __relay_write(chan, data, length) - relay_reserve(chan, length) - - callbacks: - - subbuf_start(buf, subbuf, prev_subbuf, prev_padding) - buf_mapped(buf, filp) - buf_unmapped(buf, filp) - create_buf_file(filename, parent, mode, buf, is_global) - remove_buf_file(dentry) - - helper functions: - - relay_buf_full(buf) - subbuf_start_reserve(buf, length) - - -Creating a channel ------------------- - -relay_open() is used to create a channel, along with its per-cpu -channel buffers. Each channel buffer will have an associated file -created for it in the relayfs filesystem, which can be opened and -mmapped from user space if desired. The files are named -basename0...basenameN-1 where N is the number of online cpus, and by -default will be created in the root of the filesystem. If you want a -directory structure to contain your relayfs files, you can create it -with relayfs_create_dir() and pass the parent directory to -relay_open(). Clients are responsible for cleaning up any directory -structure they create when the channel is closed - use -relayfs_remove_dir() for that. - -The total size of each per-cpu buffer is calculated by multiplying the -number of sub-buffers by the sub-buffer size passed into relay_open(). -The idea behind sub-buffers is that they're basically an extension of -double-buffering to N buffers, and they also allow applications to -easily implement random-access-on-buffer-boundary schemes, which can -be important for some high-volume applications. The number and size -of sub-buffers is completely dependent on the application and even for -the same application, different conditions will warrant different -values for these parameters at different times. Typically, the right -values to use are best decided after some experimentation; in general, -though, it's safe to assume that having only 1 sub-buffer is a bad -idea - you're guaranteed to either overwrite data or lose events -depending on the channel mode being used. - -Channel 'modes' ---------------- - -relayfs channels can be used in either of two modes - 'overwrite' or -'no-overwrite'. The mode is entirely determined by the implementation -of the subbuf_start() callback, as described below. In 'overwrite' -mode, also known as 'flight recorder' mode, writes continuously cycle -around the buffer and will never fail, but will unconditionally -overwrite old data regardless of whether it's actually been consumed. -In no-overwrite mode, writes will fail i.e. data will be lost, if the -number of unconsumed sub-buffers equals the total number of -sub-buffers in the channel. It should be clear that if there is no -consumer or if the consumer can't consume sub-buffers fast enought, -data will be lost in either case; the only difference is whether data -is lost from the beginning or the end of a buffer. - -As explained above, a relayfs channel is made of up one or more -per-cpu channel buffers, each implemented as a circular buffer -subdivided into one or more sub-buffers. Messages are written into -the current sub-buffer of the channel's current per-cpu buffer via the -write functions described below. Whenever a message can't fit into -the current sub-buffer, because there's no room left for it, the -client is notified via the subbuf_start() callback that a switch to a -new sub-buffer is about to occur. The client uses this callback to 1) -initialize the next sub-buffer if appropriate 2) finalize the previous -sub-buffer if appropriate and 3) return a boolean value indicating -whether or not to actually go ahead with the sub-buffer switch. - -To implement 'no-overwrite' mode, the userspace client would provide -an implementation of the subbuf_start() callback something like the -following: - -static int subbuf_start(struct rchan_buf *buf, - void *subbuf, - void *prev_subbuf, - unsigned int prev_padding) -{ - if (prev_subbuf) - *((unsigned *)prev_subbuf) = prev_padding; - - if (relay_buf_full(buf)) - return 0; - - subbuf_start_reserve(buf, sizeof(unsigned int)); - - return 1; -} - -If the current buffer is full i.e. all sub-buffers remain unconsumed, -the callback returns 0 to indicate that the buffer switch should not -occur yet i.e. until the consumer has had a chance to read the current -set of ready sub-buffers. For the relay_buf_full() function to make -sense, the consumer is reponsible for notifying relayfs when -sub-buffers have been consumed via relay_subbufs_consumed(). Any -subsequent attempts to write into the buffer will again invoke the -subbuf_start() callback with the same parameters; only when the -consumer has consumed one or more of the ready sub-buffers will -relay_buf_full() return 0, in which case the buffer switch can -continue. - -The implementation of the subbuf_start() callback for 'overwrite' mode -would be very similar: - -static int subbuf_start(struct rchan_buf *buf, - void *subbuf, - void *prev_subbuf, - unsigned int prev_padding) -{ - if (prev_subbuf) - *((unsigned *)prev_subbuf) = prev_padding; - - subbuf_start_reserve(buf, sizeof(unsigned int)); - - return 1; -} - -In this case, the relay_buf_full() check is meaningless and the -callback always returns 1, causing the buffer switch to occur -unconditionally. It's also meaningless for the client to use the -relay_subbufs_consumed() function in this mode, as it's never -consulted. - -The default subbuf_start() implementation, used if the client doesn't -define any callbacks, or doesn't define the subbuf_start() callback, -implements the simplest possible 'no-overwrite' mode i.e. it does -nothing but return 0. - -Header information can be reserved at the beginning of each sub-buffer -by calling the subbuf_start_reserve() helper function from within the -subbuf_start() callback. This reserved area can be used to store -whatever information the client wants. In the example above, room is -reserved in each sub-buffer to store the padding count for that -sub-buffer. This is filled in for the previous sub-buffer in the -subbuf_start() implementation; the padding value for the previous -sub-buffer is passed into the subbuf_start() callback along with a -pointer to the previous sub-buffer, since the padding value isn't -known until a sub-buffer is filled. The subbuf_start() callback is -also called for the first sub-buffer when the channel is opened, to -give the client a chance to reserve space in it. In this case the -previous sub-buffer pointer passed into the callback will be NULL, so -the client should check the value of the prev_subbuf pointer before -writing into the previous sub-buffer. - -Writing to a channel --------------------- - -kernel clients write data into the current cpu's channel buffer using -relay_write() or __relay_write(). relay_write() is the main logging -function - it uses local_irqsave() to protect the buffer and should be -used if you might be logging from interrupt context. If you know -you'll never be logging from interrupt context, you can use -__relay_write(), which only disables preemption. These functions -don't return a value, so you can't determine whether or not they -failed - the assumption is that you wouldn't want to check a return -value in the fast logging path anyway, and that they'll always succeed -unless the buffer is full and no-overwrite mode is being used, in -which case you can detect a failed write in the subbuf_start() -callback by calling the relay_buf_full() helper function. - -relay_reserve() is used to reserve a slot in a channel buffer which -can be written to later. This would typically be used in applications -that need to write directly into a channel buffer without having to -stage data in a temporary buffer beforehand. Because the actual write -may not happen immediately after the slot is reserved, applications -using relay_reserve() can keep a count of the number of bytes actually -written, either in space reserved in the sub-buffers themselves or as -a separate array. See the 'reserve' example in the relay-apps tarball -at http://relayfs.sourceforge.net for an example of how this can be -done. Because the write is under control of the client and is -separated from the reserve, relay_reserve() doesn't protect the buffer -at all - it's up to the client to provide the appropriate -synchronization when using relay_reserve(). - -Closing a channel ------------------ - -The client calls relay_close() when it's finished using the channel. -The channel and its associated buffers are destroyed when there are no -longer any references to any of the channel buffers. relay_flush() -forces a sub-buffer switch on all the channel buffers, and can be used -to finalize and process the last sub-buffers before the channel is -closed. - -Creating non-relay files ------------------------- - -relay_open() automatically creates files in the relayfs filesystem to -represent the per-cpu kernel buffers; it's often useful for -applications to be able to create their own files alongside the relay -files in the relayfs filesystem as well e.g. 'control' files much like -those created in /proc or debugfs for similar purposes, used to -communicate control information between the kernel and user sides of a -relayfs application. For this purpose the relayfs_create_file() and -relayfs_remove_file() API functions exist. For relayfs_create_file(), -the caller passes in a set of user-defined file operations to be used -for the file and an optional void * to a user-specified data item, -which will be accessible via inode->u.generic_ip (see the relay-apps -tarball for examples). The file_operations are a required parameter -to relayfs_create_file() and thus the semantics of these files are -completely defined by the caller. - -See the relay-apps tarball at http://relayfs.sourceforge.net for -examples of how these non-relay files are meant to be used. - -Creating relay files in other filesystems ------------------------------------------ - -By default of course, relay_open() creates relay files in the relayfs -filesystem. Because relay_file_operations is exported, however, it's -also possible to create and use relay files in other pseudo-filesytems -such as debugfs. - -For this purpose, two callback functions are provided, -create_buf_file() and remove_buf_file(). create_buf_file() is called -once for each per-cpu buffer from relay_open() to allow the client to -create a file to be used to represent the corresponding buffer; if -this callback is not defined, the default implementation will create -and return a file in the relayfs filesystem to represent the buffer. -The callback should return the dentry of the file created to represent -the relay buffer. Note that the parent directory passed to -relay_open() (and passed along to the callback), if specified, must -exist in the same filesystem the new relay file is created in. If -create_buf_file() is defined, remove_buf_file() must also be defined; -it's responsible for deleting the file(s) created in create_buf_file() -and is called during relay_close(). - -The create_buf_file() implementation can also be defined in such a way -as to allow the creation of a single 'global' buffer instead of the -default per-cpu set. This can be useful for applications interested -mainly in seeing the relative ordering of system-wide events without -the need to bother with saving explicit timestamps for the purpose of -merging/sorting per-cpu files in a postprocessing step. - -To have relay_open() create a global buffer, the create_buf_file() -implementation should set the value of the is_global outparam to a -non-zero value in addition to creating the file that will be used to -represent the single buffer. In the case of a global buffer, -create_buf_file() and remove_buf_file() will be called only once. The -normal channel-writing functions e.g. relay_write() can still be used -- writes from any cpu will transparently end up in the global buffer - -but since it is a global buffer, callers should make sure they use the -proper locking for such a buffer, either by wrapping writes in a -spinlock, or by copying a write function from relayfs_fs.h and -creating a local version that internally does the proper locking. - -See the 'exported-relayfile' examples in the relay-apps tarball for -examples of creating and using relay files in debugfs. - -Misc ----- - -Some applications may want to keep a channel around and re-use it -rather than open and close a new channel for each use. relay_reset() -can be used for this purpose - it resets a channel to its initial -state without reallocating channel buffer memory or destroying -existing mappings. It should however only be called when it's safe to -do so i.e. when the channel isn't currently being written to. - -Finally, there are a couple of utility callbacks that can be used for -different purposes. buf_mapped() is called whenever a channel buffer -is mmapped from user space and buf_unmapped() is called when it's -unmapped. The client can use this notification to trigger actions -within the kernel application, such as enabling/disabling logging to -the channel. - - -Resources -========= - -For news, example code, mailing list, etc. see the relayfs homepage: - - http://relayfs.sourceforge.net - - -Credits -======= - -The ideas and specs for relayfs came about as a result of discussions -on tracing involving the following: - -Michel Dagenais <michel.dagenais@polymtl.ca> -Richard Moore <richardj_moore@uk.ibm.com> -Bob Wisniewski <bob@watson.ibm.com> -Karim Yaghmour <karim@opersys.com> -Tom Zanussi <zanussi@us.ibm.com> - -Also thanks to Hubertus Franke for a lot of useful suggestions and bug -reports. diff --git a/Documentation/infiniband/ipoib.txt b/Documentation/infiniband/ipoib.txt index 187035560d7f..864ff3283780 100644 --- a/Documentation/infiniband/ipoib.txt +++ b/Documentation/infiniband/ipoib.txt @@ -51,8 +51,6 @@ Debugging Information References - IETF IP over InfiniBand (ipoib) Working Group - http://ietf.org/html.charters/ipoib-charter.html Transmission of IP over InfiniBand (IPoIB) (RFC 4391) http://ietf.org/rfc/rfc4391.txt IP over InfiniBand (IPoIB) Architecture (RFC 4392) diff --git a/Documentation/initrd.txt b/Documentation/initrd.txt index b1b6440237a6..15f1b35deb34 100644 --- a/Documentation/initrd.txt +++ b/Documentation/initrd.txt @@ -72,6 +72,22 @@ initrd adds the following new options: initrd is mounted as root, and the normal boot procedure is followed, with the RAM disk still mounted as root. +Compressed cpio images +---------------------- + +Recent kernels have support for populating a ramdisk from a compressed cpio +archive, on such systems, the creation of a ramdisk image doesn't need to +involve special block devices or loopbacks, you merely create a directory on +disk with the desired initrd content, cd to that directory, and run (as an +example): + +find . | cpio --quiet -c -o | gzip -9 -n > /boot/imagefile.img + +Examining the contents of an existing image file is just as simple: + +mkdir /tmp/imagefile +cd /tmp/imagefile +gzip -cd /boot/imagefile.img | cpio -imd --quiet Installation ------------ diff --git a/Documentation/input/joystick.txt b/Documentation/input/joystick.txt index d53b857a3710..841c353297e6 100644 --- a/Documentation/input/joystick.txt +++ b/Documentation/input/joystick.txt @@ -39,7 +39,6 @@ them. Bug reports and success stories are also welcome. The input project website is at: - http://www.suse.cz/development/input/ http://atrey.karlin.mff.cuni.cz/~vojtech/input/ There is also a mailing list for the driver at: diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 14ef3868a328..0706699c9da9 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -407,6 +407,20 @@ more details, with real examples. The second argument is optional, and if supplied will be used if first argument is not supported. + ld-option + ld-option is used to check if $(CC) when used to link object files + supports the given option. An optional second option may be + specified if first option are not supported. + + Example: + #arch/i386/kernel/Makefile + vsyscall-flags += $(call ld-option, -Wl$(comma)--hash-style=sysv) + + In the above example vsyscall-flags will be assigned the option + -Wl$(comma)--hash-style=sysv if it is supported by $(CC). + The second argument is optional, and if supplied will be used + if first argument is not supported. + cc-option cc-option is used to check if $(CC) support a given option, and not supported to use an optional second option. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index e11f7728ec6f..b50595a0550f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -448,8 +448,6 @@ running once the system is up. Format: <area>[,<node>] See also Documentation/networking/decnet.txt. - delayacct [KNL] Enable per-task delay accounting - dhash_entries= [KNL] Set number of hash buckets for dentry cache. @@ -1031,6 +1029,8 @@ running once the system is up. nocache [ARM] + nodelayacct [KNL] Disable per-task delay accounting + nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. noexec [IA-64] diff --git a/Documentation/kobject.txt b/Documentation/kobject.txt index 8d9bffbd192c..949f7b5a2053 100644 --- a/Documentation/kobject.txt +++ b/Documentation/kobject.txt @@ -247,7 +247,7 @@ the object-specific fields, which include: - default_attrs: Default attributes to be exported via sysfs when the object is registered.Note that the last attribute has to be initialized to NULL ! You can find a complete implementation - in drivers/block/genhd.c + in block/genhd.c Instances of struct kobj_type are not registered; only referenced by diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index d46338af6002..3e0c017e7877 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -294,15 +294,15 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max Default: 87380*2 bytes. tcp_mem - vector of 3 INTEGERs: min, pressure, max - low: below this number of pages TCP is not bothered about its + min: below this number of pages TCP is not bothered about its memory appetite. pressure: when amount of memory allocated by TCP exceeds this number of pages, TCP moderates its memory consumption and enters memory pressure mode, which is exited when memory consumption falls - under "low". + under "min". - high: number of pages allowed for queueing by all TCP sockets. + max: number of pages allowed for queueing by all TCP sockets. Defaults are calculated at boot time from amount of available memory. diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt index 3c62e66e1fcc..8c48b8a27b9c 100644 --- a/Documentation/powerpc/booting-without-of.txt +++ b/Documentation/powerpc/booting-without-of.txt @@ -1196,7 +1196,7 @@ platforms are moved over to use the flattened-device-tree model. - model : Model of the device. Can be "TSEC", "eTSEC", or "FEC" - compatible : Should be "gianfar" - reg : Offset and length of the register set for the device - - address : List of bytes representing the ethernet address of + - mac-address : List of bytes representing the ethernet address of this controller - interrupts : <a b> where a is the interrupt number and b is a field that represents an encoding of the sense and level @@ -1216,7 +1216,7 @@ platforms are moved over to use the flattened-device-tree model. model = "TSEC"; compatible = "gianfar"; reg = <24000 1000>; - address = [ 00 E0 0C 00 73 00 ]; + mac-address = [ 00 E0 0C 00 73 00 ]; interrupts = <d 3 e 3 12 3>; interrupt-parent = <40000>; phy-handle = <2452000> @@ -1498,7 +1498,7 @@ not necessary as they are usually the same as the root node. model = "TSEC"; compatible = "gianfar"; reg = <24000 1000>; - address = [ 00 E0 0C 00 73 00 ]; + mac-address = [ 00 E0 0C 00 73 00 ]; interrupts = <d 3 e 3 12 3>; interrupt-parent = <40000>; phy-handle = <2452000>; @@ -1511,7 +1511,7 @@ not necessary as they are usually the same as the root node. model = "TSEC"; compatible = "gianfar"; reg = <25000 1000>; - address = [ 00 E0 0C 00 73 01 ]; + mac-address = [ 00 E0 0C 00 73 01 ]; interrupts = <13 3 14 3 18 3>; interrupt-parent = <40000>; phy-handle = <2452001>; @@ -1524,7 +1524,7 @@ not necessary as they are usually the same as the root node. model = "FEC"; compatible = "gianfar"; reg = <26000 1000>; - address = [ 00 E0 0C 00 73 02 ]; + mac-address = [ 00 E0 0C 00 73 02 ]; interrupts = <19 3>; interrupt-parent = <40000>; phy-handle = <2452002>; diff --git a/Documentation/scsi/ChangeLog.megaraid b/Documentation/scsi/ChangeLog.megaraid index c173806c91fa..a056bbe67c7e 100644 --- a/Documentation/scsi/ChangeLog.megaraid +++ b/Documentation/scsi/ChangeLog.megaraid @@ -1,3 +1,126 @@ +Release Date : Fri May 19 09:31:45 EST 2006 - Seokmann Ju <sju@lsil.com> +Current Version : 2.20.4.9 (scsi module), 2.20.2.6 (cmm module) +Older Version : 2.20.4.8 (scsi module), 2.20.2.6 (cmm module) + +1. Fixed a bug in megaraid_init_mbox(). + Customer reported "garbage in file on x86_64 platform". + Root Cause: the driver registered controllers as 64-bit DMA capable + for those which are not support it. + Fix: Made change in the function inserting identification machanism + identifying 64-bit DMA capable controllers. + + > -----Original Message----- + > From: Vasily Averin [mailto:vvs@sw.ru] + > Sent: Thursday, May 04, 2006 2:49 PM + > To: linux-scsi@vger.kernel.org; Kolli, Neela; Mukker, Atul; + > Ju, Seokmann; Bagalkote, Sreenivas; + > James.Bottomley@SteelEye.com; devel@openvz.org + > Subject: megaraid_mbox: garbage in file + > + > Hello all, + > + > I've investigated customers claim on the unstable work of + > their node and found a + > strange effect: reading from some files leads to the + > "attempt to access beyond end of device" messages. + > + > I've checked filesystem, memory on the node, motherboard BIOS + > version, but it + > does not help and issue still has been reproduced by simple + > file reading. + > + > Reproducer is simple: + > + > echo 0xffffffff >/proc/sys/dev/scsi/logging_level ; + > cat /vz/private/101/root/etc/ld.so.cache >/tmp/ttt ; + > echo 0 >/proc/sys/dev/scsi/logging + > + > It leads to the following messages in dmesg + > + > sd_init_command: disk=sda, block=871769260, count=26 + > sda : block=871769260 + > sda : reading 26/26 512 byte blocks. + > scsi_add_timer: scmd: f79ed980, time: 7500, (c02b1420) + > sd 0:1:0:0: send 0xf79ed980 sd 0:1:0:0: + > command: Read (10): 28 00 33 f6 24 ac 00 00 1a 00 + > buffer = 0xf7cfb540, bufflen = 13312, done = 0xc0366b40, + > queuecommand 0xc0344010 + > leaving scsi_dispatch_cmnd() + > scsi_delete_timer: scmd: f79ed980, rtn: 1 + > sd 0:1:0:0: done 0xf79ed980 SUCCESS 0 sd 0:1:0:0: + > command: Read (10): 28 00 33 f6 24 ac 00 00 1a 00 + > scsi host busy 1 failed 0 + > sd 0:1:0:0: Notifying upper driver of completion (result 0) + > sd_rw_intr: sda: res=0x0 + > 26 sectors total, 13312 bytes done. + > use_sg is 4 + > attempt to access beyond end of device + > sda6: rw=0, want=1044134458, limit=951401367 + > Buffer I/O error on device sda6, logical block 522067228 + > attempt to access beyond end of device + +2. When INQUIRY with EVPD bit set issued to the MegaRAID controller, + system memory gets corrupted. + Root Cause: MegaRAID F/W handle the INQUIRY with EVPD bit set + incorrectly. + Fix: MegaRAID F/W has fixed the problem and being process of release, + soon. Meanwhile, driver will filter out the request. + +3. One of member in the data structure of the driver leads unaligne + issue on 64-bit platform. + Customer reporeted "kernel unaligned access addrss" issue when + application communicates with MegaRAID HBA driver. + Root Cause: in uioc_t structure, one of member had misaligned and it + led system to display the error message. + Fix: A patch submitted to community from following folk. + + > -----Original Message----- + > From: linux-scsi-owner@vger.kernel.org + > [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Sakurai Hiroomi + > Sent: Wednesday, July 12, 2006 4:20 AM + > To: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org + > Subject: Re: Help: strange messages from kernel on IA64 platform + > + > Hi, + > + > I saw same message. + > + > When GAM(Global Array Manager) is started, The following + > message output. + > kernel: kernel unaligned access to 0xe0000001fe1080d4, + > ip=0xa000000200053371 + > + > The uioc structure used by ioctl is defined by packed, + > the allignment of each member are disturbed. + > In a 64 bit structure, the allignment of member doesn't fit 64 bit + > boundary. this causes this messages. + > In a 32 bit structure, we don't see the message because the allinment + > of member fit 32 bit boundary even if packed is specified. + > + > patch + > I Add 32 bit dummy member to fit 64 bit boundary. I tested. + > We confirmed this patch fix the problem by IA64 server. + > + > ************************************************************** + > **************** + > --- linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h.orig + > 2006-04-03 17:13:03.000000000 +0900 + > +++ linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h + > 2006-04-03 17:14:09.000000000 +0900 + > @@ -132,6 +132,10 @@ + > /* Driver Data: */ + > void __user * user_data; + > uint32_t user_data_len; + > + + > + /* 64bit alignment */ + > + uint32_t pad_0xBC; + > + + > mraid_passthru_t __user *user_pthru; + > + > mraid_passthru_t *pthru32; + > ************************************************************** + > **************** + Release Date : Mon Apr 11 12:27:22 EST 2006 - Seokmann Ju <sju@lsil.com> Current Version : 2.20.4.8 (scsi module), 2.20.2.6 (cmm module) Older Version : 2.20.4.7 (scsi module), 2.20.2.6 (cmm module) diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt index 0b62c62142cf..5c3a51905969 100644 --- a/Documentation/sysctl/fs.txt +++ b/Documentation/sysctl/fs.txt @@ -25,6 +25,7 @@ Currently, these files are in /proc/sys/fs: - inode-state - overflowuid - overflowgid +- suid_dumpable - super-max - super-nr @@ -131,6 +132,25 @@ The default is 65534. ============================================================== +suid_dumpable: + +This value can be used to query and set the core dump mode for setuid +or otherwise protected/tainted binaries. The modes are + +0 - (default) - traditional behaviour. Any process which has changed + privilege levels or is execute only will not be dumped +1 - (debug) - all processes dump core when possible. The core dump is + owned by the current user and no security is applied. This is + intended for system debugging situations only. Ptrace is unchecked. +2 - (suidsafe) - any binary which normally would not be dumped is dumped + readable by root only. This allows the end user to remove + such a dump but not access it directly. For security reasons + core dumps in this mode will not overwrite one another or + other files. This mode is appropriate when adminstrators are + attempting to debug problems in a normal environment. + +============================================================== + super-max & super-nr: These numbers control the maximum number of superblocks, and diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index b0c7ab93dcb9..89bf8c20a586 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -50,7 +50,6 @@ show up in /proc/sys/kernel: - shmmax [ sysv ipc ] - shmmni - stop-a [ SPARC only ] -- suid_dumpable - sysrq ==> Documentation/sysrq.txt - tainted - threads-max @@ -211,9 +210,8 @@ Controls the kernel's behaviour when an oops or BUG is encountered. 0: try to continue operation -1: delay a few seconds (to give klogd time to record the oops output) and - then panic. If the `panic' sysctl is also non-zero then the machine will - be rebooted. +1: panic immediatly. If the `panic' sysctl is also non-zero then the + machine will be rebooted. ============================================================== @@ -311,25 +309,6 @@ kernel. This value defaults to SHMMAX. ============================================================== -suid_dumpable: - -This value can be used to query and set the core dump mode for setuid -or otherwise protected/tainted binaries. The modes are - -0 - (default) - traditional behaviour. Any process which has changed - privilege levels or is execute only will not be dumped -1 - (debug) - all processes dump core when possible. The core dump is - owned by the current user and no security is applied. This is - intended for system debugging situations only. Ptrace is unchecked. -2 - (suidsafe) - any binary which normally would not be dumped is dumped - readable by root only. This allows the end user to remove - such a dump but not access it directly. For security reasons - core dumps in this mode will not overwrite one another or - other files. This mode is appropriate when adminstrators are - attempting to debug problems in a normal environment. - -============================================================== - tainted: Non-zero if the kernel has been tainted. Numeric values, which diff --git a/Documentation/usb/proc_usb_info.txt b/Documentation/usb/proc_usb_info.txt index f86550fe38ee..22c5331260ca 100644 --- a/Documentation/usb/proc_usb_info.txt +++ b/Documentation/usb/proc_usb_info.txt @@ -59,7 +59,7 @@ bind to an interface (or perhaps several) using an ioctl call. You would issue more ioctls to the device to communicate to it using control, bulk, or other kinds of USB transfers. The IOCTLs are listed in the <linux/usbdevice_fs.h> file, and at this writing the -source code (linux/drivers/usb/devio.c) is the primary reference +source code (linux/drivers/usb/core/devio.c) is the primary reference for how to access devices through those files. Note that since by default these BBB/DDD files are writable only by diff --git a/Documentation/usb/usb-help.txt b/Documentation/usb/usb-help.txt index b7c324973695..a7408593829f 100644 --- a/Documentation/usb/usb-help.txt +++ b/Documentation/usb/usb-help.txt @@ -5,8 +5,7 @@ For USB help other than the readme files that are located in Documentation/usb/*, see the following: Linux-USB project: http://www.linux-usb.org - mirrors at http://www.suse.cz/development/linux-usb/ - and http://usb.in.tum.de/linux-usb/ + mirrors at http://usb.in.tum.de/linux-usb/ and http://it.linux-usb.org Linux USB Guide: http://linux-usb.sourceforge.net Linux-USB device overview (working devices and drivers): diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt index 6887d44d2661..6da24e7a56cb 100644 --- a/Documentation/x86_64/boot-options.txt +++ b/Documentation/x86_64/boot-options.txt @@ -238,6 +238,13 @@ Debugging pagefaulttrace Dump all page faults. Only useful for extreme debugging and will create a lot of output. + call_trace=[old|both|newfallback|new] + old: use old inexact backtracer + new: use new exact dwarf2 unwinder + both: print entries from both + newfallback: use new unwinder but fall back to old if it gets + stuck (default) + Misc noreplacement Don't replace instructions with more appropriate ones |