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-rw-r--r--Documentation/ABI/testing/sysfs-bus-usb2
-rw-r--r--Documentation/filesystems/ceph.txt139
-rw-r--r--Documentation/ioctl/ioctl-number.txt1
-rw-r--r--Documentation/kobject.txt60
-rw-r--r--Documentation/networking/stmmac.txt143
5 files changed, 324 insertions, 21 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index a986e9bbba3d..bcebb9eaedce 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -160,7 +160,7 @@ Description:
160 match the driver to the device. For example: 160 match the driver to the device. For example:
161 # echo "046d c315" > /sys/bus/usb/drivers/foo/remove_id 161 # echo "046d c315" > /sys/bus/usb/drivers/foo/remove_id
162 162
163What: /sys/bus/usb/device/.../avoid_reset 163What: /sys/bus/usb/device/.../avoid_reset_quirk
164Date: December 2009 164Date: December 2009
165Contact: Oliver Neukum <oliver@neukum.org> 165Contact: Oliver Neukum <oliver@neukum.org>
166Description: 166Description:
diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt
new file mode 100644
index 000000000000..6e03917316bd
--- /dev/null
+++ b/Documentation/filesystems/ceph.txt
@@ -0,0 +1,139 @@
1Ceph Distributed File System
2============================
3
4Ceph is a distributed network file system designed to provide good
5performance, reliability, and scalability.
6
7Basic features include:
8
9 * POSIX semantics
10 * Seamless scaling from 1 to many thousands of nodes
11 * High availability and reliability. No single points of failure.
12 * N-way replication of data across storage nodes
13 * Fast recovery from node failures
14 * Automatic rebalancing of data on node addition/removal
15 * Easy deployment: most FS components are userspace daemons
16
17Also,
18 * Flexible snapshots (on any directory)
19 * Recursive accounting (nested files, directories, bytes)
20
21In contrast to cluster filesystems like GFS, OCFS2, and GPFS that rely
22on symmetric access by all clients to shared block devices, Ceph
23separates data and metadata management into independent server
24clusters, similar to Lustre. Unlike Lustre, however, metadata and
25storage nodes run entirely as user space daemons. Storage nodes
26utilize btrfs to store data objects, leveraging its advanced features
27(checksumming, metadata replication, etc.). File data is striped
28across storage nodes in large chunks to distribute workload and
29facilitate high throughputs. When storage nodes fail, data is
30re-replicated in a distributed fashion by the storage nodes themselves
31(with some minimal coordination from a cluster monitor), making the
32system extremely efficient and scalable.
33
34Metadata servers effectively form a large, consistent, distributed
35in-memory cache above the file namespace that is extremely scalable,
36dynamically redistributes metadata in response to workload changes,
37and can tolerate arbitrary (well, non-Byzantine) node failures. The
38metadata server takes a somewhat unconventional approach to metadata
39storage to significantly improve performance for common workloads. In
40particular, inodes with only a single link are embedded in
41directories, allowing entire directories of dentries and inodes to be
42loaded into its cache with a single I/O operation. The contents of
43extremely large directories can be fragmented and managed by
44independent metadata servers, allowing scalable concurrent access.
45
46The system offers automatic data rebalancing/migration when scaling
47from a small cluster of just a few nodes to many hundreds, without
48requiring an administrator carve the data set into static volumes or
49go through the tedious process of migrating data between servers.
50When the file system approaches full, new nodes can be easily added
51and things will "just work."
52
53Ceph includes flexible snapshot mechanism that allows a user to create
54a snapshot on any subdirectory (and its nested contents) in the
55system. Snapshot creation and deletion are as simple as 'mkdir
56.snap/foo' and 'rmdir .snap/foo'.
57
58Ceph also provides some recursive accounting on directories for nested
59files and bytes. That is, a 'getfattr -d foo' on any directory in the
60system will reveal the total number of nested regular files and
61subdirectories, and a summation of all nested file sizes. This makes
62the identification of large disk space consumers relatively quick, as
63no 'du' or similar recursive scan of the file system is required.
64
65
66Mount Syntax
67============
68
69The basic mount syntax is:
70
71 # mount -t ceph monip[:port][,monip2[:port]...]:/[subdir] mnt
72
73You only need to specify a single monitor, as the client will get the
74full list when it connects. (However, if the monitor you specify
75happens to be down, the mount won't succeed.) The port can be left
76off if the monitor is using the default. So if the monitor is at
771.2.3.4,
78
79 # mount -t ceph 1.2.3.4:/ /mnt/ceph
80
81is sufficient. If /sbin/mount.ceph is installed, a hostname can be
82used instead of an IP address.
83
84
85
86Mount Options
87=============
88
89 ip=A.B.C.D[:N]
90 Specify the IP and/or port the client should bind to locally.
91 There is normally not much reason to do this. If the IP is not
92 specified, the client's IP address is determined by looking at the
93 address it's connection to the monitor originates from.
94
95 wsize=X
96 Specify the maximum write size in bytes. By default there is no
97 maximu. Ceph will normally size writes based on the file stripe
98 size.
99
100 rsize=X
101 Specify the maximum readahead.
102
103 mount_timeout=X
104 Specify the timeout value for mount (in seconds), in the case
105 of a non-responsive Ceph file system. The default is 30
106 seconds.
107
108 rbytes
109 When stat() is called on a directory, set st_size to 'rbytes',
110 the summation of file sizes over all files nested beneath that
111 directory. This is the default.
112
113 norbytes
114 When stat() is called on a directory, set st_size to the
115 number of entries in that directory.
116
117 nocrc
118 Disable CRC32C calculation for data writes. If set, the OSD
119 must rely on TCP's error correction to detect data corruption
120 in the data payload.
121
122 noasyncreaddir
123 Disable client's use its local cache to satisfy readdir
124 requests. (This does not change correctness; the client uses
125 cached metadata only when a lease or capability ensures it is
126 valid.)
127
128
129More Information
130================
131
132For more information on Ceph, see the home page at
133 http://ceph.newdream.net/
134
135The Linux kernel client source tree is available at
136 git://ceph.newdream.net/linux-ceph-client.git
137
138and the source for the full system is at
139 git://ceph.newdream.net/ceph.git
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 35c9b51d20ea..dd5806f4fcc4 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -291,6 +291,7 @@ Code Seq#(hex) Include File Comments
2910x92 00-0F drivers/usb/mon/mon_bin.c 2910x92 00-0F drivers/usb/mon/mon_bin.c
2920x93 60-7F linux/auto_fs.h 2920x93 60-7F linux/auto_fs.h
2930x94 all fs/btrfs/ioctl.h 2930x94 all fs/btrfs/ioctl.h
2940x97 00-7F fs/ceph/ioctl.h Ceph file system
2940x99 00-0F 537-Addinboard driver 2950x99 00-0F 537-Addinboard driver
295 <mailto:buk@buks.ipn.de> 296 <mailto:buk@buks.ipn.de>
2960xA0 all linux/sdp/sdp.h Industrial Device Project 2970xA0 all linux/sdp/sdp.h Industrial Device Project
diff --git a/Documentation/kobject.txt b/Documentation/kobject.txt
index bdb13817e1e9..3ab2472509cb 100644
--- a/Documentation/kobject.txt
+++ b/Documentation/kobject.txt
@@ -59,37 +59,56 @@ nice to have in other objects. The C language does not allow for the
59direct expression of inheritance, so other techniques - such as structure 59direct expression of inheritance, so other techniques - such as structure
60embedding - must be used. 60embedding - must be used.
61 61
62So, for example, the UIO code has a structure that defines the memory 62(As an aside, for those familiar with the kernel linked list implementation,
63region associated with a uio device: 63this is analogous as to how "list_head" structs are rarely useful on
64their own, but are invariably found embedded in the larger objects of
65interest.)
64 66
65struct uio_mem { 67So, for example, the UIO code in drivers/uio/uio.c has a structure that
68defines the memory region associated with a uio device:
69
70 struct uio_map {
66 struct kobject kobj; 71 struct kobject kobj;
67 unsigned long addr; 72 struct uio_mem *mem;
68 unsigned long size; 73 };
69 int memtype;
70 void __iomem *internal_addr;
71};
72 74
73If you have a struct uio_mem structure, finding its embedded kobject is 75If you have a struct uio_map structure, finding its embedded kobject is
74just a matter of using the kobj member. Code that works with kobjects will 76just a matter of using the kobj member. Code that works with kobjects will
75often have the opposite problem, however: given a struct kobject pointer, 77often have the opposite problem, however: given a struct kobject pointer,
76what is the pointer to the containing structure? You must avoid tricks 78what is the pointer to the containing structure? You must avoid tricks
77(such as assuming that the kobject is at the beginning of the structure) 79(such as assuming that the kobject is at the beginning of the structure)
78and, instead, use the container_of() macro, found in <linux/kernel.h>: 80and, instead, use the container_of() macro, found in <linux/kernel.h>:
79 81
80 container_of(pointer, type, member) 82 container_of(pointer, type, member)
83
84where:
85
86 * "pointer" is the pointer to the embedded kobject,
87 * "type" is the type of the containing structure, and
88 * "member" is the name of the structure field to which "pointer" points.
89
90The return value from container_of() is a pointer to the corresponding
91container type. So, for example, a pointer "kp" to a struct kobject
92embedded *within* a struct uio_map could be converted to a pointer to the
93*containing* uio_map structure with:
94
95 struct uio_map *u_map = container_of(kp, struct uio_map, kobj);
96
97For convenience, programmers often define a simple macro for "back-casting"
98kobject pointers to the containing type. Exactly this happens in the
99earlier drivers/uio/uio.c, as you can see here:
100
101 struct uio_map {
102 struct kobject kobj;
103 struct uio_mem *mem;
104 };
81 105
82where pointer is the pointer to the embedded kobject, type is the type of 106 #define to_map(map) container_of(map, struct uio_map, kobj)
83the containing structure, and member is the name of the structure field to
84which pointer points. The return value from container_of() is a pointer to
85the given type. So, for example, a pointer "kp" to a struct kobject
86embedded within a struct uio_mem could be converted to a pointer to the
87containing uio_mem structure with:
88 107
89 struct uio_mem *u_mem = container_of(kp, struct uio_mem, kobj); 108where the macro argument "map" is a pointer to the struct kobject in
109question. That macro is subsequently invoked with:
90 110
91Programmers often define a simple macro for "back-casting" kobject pointers 111 struct uio_map *map = to_map(kobj);
92to the containing type.
93 112
94 113
95Initialization of kobjects 114Initialization of kobjects
@@ -387,4 +406,5 @@ called, and the objects in the former circle release each other.
387Example code to copy from 406Example code to copy from
388 407
389For a more complete example of using ksets and kobjects properly, see the 408For a more complete example of using ksets and kobjects properly, see the
390sample/kobject/kset-example.c code. 409example programs samples/kobject/{kobject-example.c,kset-example.c},
410which will be built as loadable modules if you select CONFIG_SAMPLE_KOBJECT.
diff --git a/Documentation/networking/stmmac.txt b/Documentation/networking/stmmac.txt
new file mode 100644
index 000000000000..7ee770b5ef5f
--- /dev/null
+++ b/Documentation/networking/stmmac.txt
@@ -0,0 +1,143 @@
1 STMicroelectronics 10/100/1000 Synopsys Ethernet driver
2
3Copyright (C) 2007-2010 STMicroelectronics Ltd
4Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
5
6This is the driver for the MAC 10/100/1000 on-chip Ethernet controllers
7(Synopsys IP blocks); it has been fully tested on STLinux platforms.
8
9Currently this network device driver is for all STM embedded MAC/GMAC
10(7xxx SoCs).
11
12DWC Ether MAC 10/100/1000 Universal version 3.41a and DWC Ether MAC 10/100
13Universal version 4.0 have been used for developing the first code
14implementation.
15
16Please, for more information also visit: www.stlinux.com
17
181) Kernel Configuration
19The kernel configuration option is STMMAC_ETH:
20 Device Drivers ---> Network device support ---> Ethernet (1000 Mbit) --->
21 STMicroelectronics 10/100/1000 Ethernet driver (STMMAC_ETH)
22
232) Driver parameters list:
24 debug: message level (0: no output, 16: all);
25 phyaddr: to manually provide the physical address to the PHY device;
26 dma_rxsize: DMA rx ring size;
27 dma_txsize: DMA tx ring size;
28 buf_sz: DMA buffer size;
29 tc: control the HW FIFO threshold;
30 tx_coe: Enable/Disable Tx Checksum Offload engine;
31 watchdog: transmit timeout (in milliseconds);
32 flow_ctrl: Flow control ability [on/off];
33 pause: Flow Control Pause Time;
34 tmrate: timer period (only if timer optimisation is configured).
35
363) Command line options
37Driver parameters can be also passed in command line by using:
38 stmmaceth=dma_rxsize:128,dma_txsize:512
39
404) Driver information and notes
41
424.1) Transmit process
43The xmit method is invoked when the kernel needs to transmit a packet; it sets
44the descriptors in the ring and informs the DMA engine that there is a packet
45ready to be transmitted.
46Once the controller has finished transmitting the packet, an interrupt is
47triggered; So the driver will be able to release the socket buffers.
48By default, the driver sets the NETIF_F_SG bit in the features field of the
49net_device structure enabling the scatter/gather feature.
50
514.2) Receive process
52When one or more packets are received, an interrupt happens. The interrupts
53are not queued so the driver has to scan all the descriptors in the ring during
54the receive process.
55This is based on NAPI so the interrupt handler signals only if there is work to be
56done, and it exits.
57Then the poll method will be scheduled at some future point.
58The incoming packets are stored, by the DMA, in a list of pre-allocated socket
59buffers in order to avoid the memcpy (Zero-copy).
60
614.3) Timer-Driver Interrupt
62Instead of having the device that asynchronously notifies the frame receptions, the
63driver configures a timer to generate an interrupt at regular intervals.
64Based on the granularity of the timer, the frames that are received by the device
65will experience different levels of latency. Some NICs have dedicated timer
66device to perform this task. STMMAC can use either the RTC device or the TMU
67channel 2 on STLinux platforms.
68The timers frequency can be passed to the driver as parameter; when change it,
69take care of both hardware capability and network stability/performance impact.
70Several performance tests on STM platforms showed this optimisation allows to spare
71the CPU while having the maximum throughput.
72
734.4) WOL
74Wake up on Lan feature through Magic Frame is only supported for the GMAC
75core.
76
774.5) DMA descriptors
78Driver handles both normal and enhanced descriptors. The latter has been only
79tested on DWC Ether MAC 10/100/1000 Universal version 3.41a.
80
814.6) Ethtool support
82Ethtool is supported. Driver statistics and internal errors can be taken using:
83ethtool -S ethX command. It is possible to dump registers etc.
84
854.7) Jumbo and Segmentation Offloading
86Jumbo frames are supported and tested for the GMAC.
87The GSO has been also added but it's performed in software.
88LRO is not supported.
89
904.8) Physical
91The driver is compatible with PAL to work with PHY and GPHY devices.
92
934.9) Platform information
94Several information came from the platform; please refer to the
95driver's Header file in include/linux directory.
96
97struct plat_stmmacenet_data {
98 int bus_id;
99 int pbl;
100 int has_gmac;
101 void (*fix_mac_speed)(void *priv, unsigned int speed);
102 void (*bus_setup)(unsigned long ioaddr);
103#ifdef CONFIG_STM_DRIVERS
104 struct stm_pad_config *pad_config;
105#endif
106 void *bsp_priv;
107};
108
109Where:
110- pbl (Programmable Burst Length) is maximum number of
111 beats to be transferred in one DMA transaction.
112 GMAC also enables the 4xPBL by default.
113- fix_mac_speed and bus_setup are used to configure internal target
114 registers (on STM platforms);
115- has_gmac: GMAC core is on board (get it at run-time in the next step);
116- bus_id: bus identifier.
117
118struct plat_stmmacphy_data {
119 int bus_id;
120 int phy_addr;
121 unsigned int phy_mask;
122 int interface;
123 int (*phy_reset)(void *priv);
124 void *priv;
125};
126
127Where:
128- bus_id: bus identifier;
129- phy_addr: physical address used for the attached phy device;
130 set it to -1 to get it at run-time;
131- interface: physical MII interface mode;
132- phy_reset: hook to reset HW function.
133
134TODO:
135- Continue to make the driver more generic and suitable for other Synopsys
136 Ethernet controllers used on other architectures (i.e. ARM).
137- 10G controllers are not supported.
138- MAC uses Normal descriptors and GMAC uses enhanced ones.
139 This is a limit that should be reviewed. MAC could want to
140 use the enhanced structure.
141- Checksumming: Rx/Tx csum is done in HW in case of GMAC only.
142- Review the timer optimisation code to use an embedded device that seems to be
143 available in new chip generations.