diff options
Diffstat (limited to 'Documentation/s390')
| -rw-r--r-- | Documentation/s390/00-INDEX | 28 | ||||
| -rw-r--r-- | Documentation/s390/3270.txt | 25 | ||||
| -rw-r--r-- | Documentation/s390/CommonIO | 80 | ||||
| -rw-r--r-- | Documentation/s390/Debugging390.txt | 175 | ||||
| -rw-r--r-- | Documentation/s390/TAPE | 122 | ||||
| -rw-r--r-- | Documentation/s390/cds.txt | 156 | ||||
| -rw-r--r-- | Documentation/s390/crypto/crypto-API.txt | 83 | ||||
| -rw-r--r-- | Documentation/s390/driver-model.txt | 54 | ||||
| -rw-r--r-- | Documentation/s390/kvm.txt | 125 | ||||
| -rw-r--r-- | Documentation/s390/monreader.txt | 4 | ||||
| -rw-r--r-- | Documentation/s390/qeth.txt | 50 | ||||
| -rw-r--r-- | Documentation/s390/s390dbf.txt | 63 | ||||
| -rw-r--r-- | Documentation/s390/zfcpdump.txt | 52 |
13 files changed, 513 insertions, 504 deletions
diff --git a/Documentation/s390/00-INDEX b/Documentation/s390/00-INDEX new file mode 100644 index 00000000000..10c874ebdfe --- /dev/null +++ b/Documentation/s390/00-INDEX @@ -0,0 +1,28 @@ +00-INDEX + - this file. +3270.ChangeLog + - ChangeLog for the UTS Global 3270-support patch (outdated). +3270.txt + - how to use the IBM 3270 display system support. +cds.txt + - s390 common device support (common I/O layer). +CommonIO + - common I/O layer command line parameters, procfs and debugfs entries +config3270.sh + - example configuration for 3270 devices. +DASD + - information on the DASD disk device driver. +Debugging390.txt + - hints for debugging on s390 systems. +driver-model.txt + - information on s390 devices and the driver model. +kvm.txt + - ioctl calls to /dev/kvm on s390. +monreader.txt + - information on accessing the z/VM monitor stream from Linux. +qeth.txt + - HiperSockets Bridge Port Support. +s390dbf.txt + - information on using the s390 debug feature. +zfcpdump.txt + - information on the s390 SCSI dump tool. diff --git a/Documentation/s390/3270.txt b/Documentation/s390/3270.txt index 0a044e647d2..7c715de9977 100644 --- a/Documentation/s390/3270.txt +++ b/Documentation/s390/3270.txt @@ -47,9 +47,9 @@ including the console 3270, changes subchannel identifier relative to one another. ReIPL as soon as possible after running the configuration script and the resulting /tmp/mkdev3270. -If you have chosen to make tub3270 a module, you add a line to -/etc/modprobe.conf. If you are working on a VM virtual machine, you -can use DEF GRAF to define virtual 3270 devices. +If you have chosen to make tub3270 a module, you add a line to a +configuration file under /etc/modprobe.d/. If you are working on a VM +virtual machine, you can use DEF GRAF to define virtual 3270 devices. You may generate both 3270 and 3215 console support, or one or the other, or neither. If you generate both, the console type under VM is @@ -60,7 +60,7 @@ at boot time to a 3270 if it is a 3215. In brief, these are the steps: 1. Install the tub3270 patch - 2. (If a module) add a line to /etc/modprobe.conf + 2. (If a module) add a line to a file in /etc/modprobe.d/*.conf 3. (If VM) define devices with DEF GRAF 4. Reboot 5. Configure @@ -84,13 +84,12 @@ Here are the installation steps in detail: make modules_install 2. (Perform this step only if you have configured tub3270 as a - module.) Add a line to /etc/modprobe.conf to automatically - load the driver when it's needed. With this line added, - you will see login prompts appear on your 3270s as soon as - boot is complete (or with emulated 3270s, as soon as you dial - into your vm guest using the command "DIAL <vmguestname>"). - Since the line-mode major number is 227, the line to add to - /etc/modprobe.conf should be: + module.) Add a line to a file /etc/modprobe.d/*.conf to automatically + load the driver when it's needed. With this line added, you will see + login prompts appear on your 3270s as soon as boot is complete (or + with emulated 3270s, as soon as you dial into your vm guest using the + command "DIAL <vmguestname>"). Since the line-mode major number is + 227, the line to add should be: alias char-major-227 tub3270 3. Define graphic devices to your vm guest machine, if you @@ -111,9 +110,7 @@ Here are the installation steps in detail: config3270.sh. Inspect the output script it produces, /tmp/mkdev3270, and then run that script. This will create the necessary character special device files and make the necessary - changes to /etc/inittab. If you have selected DEVFS, the driver - itself creates the device files, and /tmp/mkdev3270 only changes - /etc/inittab. + changes to /etc/inittab. Then notify /sbin/init that /etc/inittab has changed, by issuing the telinit command with the q operand: diff --git a/Documentation/s390/CommonIO b/Documentation/s390/CommonIO index 59d1166d41e..6e0f63f343b 100644 --- a/Documentation/s390/CommonIO +++ b/Documentation/s390/CommonIO @@ -1,22 +1,16 @@ -S/390 common I/O-Layer - command line parameters and /proc entries -================================================================== +S/390 common I/O-Layer - command line parameters, procfs and debugfs entries +============================================================================ Command line parameters ----------------------- -* cio_msg = yes | no - - Determines whether information on found devices and sensed device - characteristics should be shown during startup, i. e. messages of the types - "Detected device 0.0.4711 on subchannel 0.0.0042" and "SenseID: Device - 0.0.4711 reports: ...". +* ccw_timeout_log - Default is off. + Enable logging of debug information in case of ccw device timeouts. +* cio_ignore = device[,device[,..]] -* cio_ignore = {all} | - {<device> | <range of devices>} | - {!<device> | !<range of devices>} + device := {all | [!]ipldev | [!]condev | [!]<devno> | [!]<devno>-<devno>} The given devices will be ignored by the common I/O-layer; no detection and device sensing will be done on any of those devices. The subchannel to @@ -26,10 +20,14 @@ Command line parameters An ignored device can be un-ignored later; see the "/proc entries"-section for details. - The devices must be given either as bus ids (0.0.abcd) or as hexadecimal - device numbers (0xabcd or abcd, for 2.4 backward compatibility). - You can use the 'all' keyword to ignore all devices. - The '!' operator will cause the I/O-layer to _not_ ignore a device. + The devices must be given either as bus ids (0.x.abcd) or as hexadecimal + device numbers (0xabcd or abcd, for 2.4 backward compatibility). If you + give a device number 0xabcd, it will be interpreted as 0.0.abcd. + + You can use the 'all' keyword to ignore all devices. The 'ipldev' and 'condev' + keywords can be used to refer to the CCW based boot device and CCW console + device respectively (these are probably useful only when combined with the '!' + operator). The '!' operator will cause the I/O-layer to _not_ ignore a device. The command line is parsed from left to right. For example, @@ -66,7 +64,7 @@ Command line parameters When a device is un-ignored, device recognition and sensing is performed and the device driver will be notified if possible, so the device will become - available to the system. + available to the system. Note that un-ignoring is performed asynchronously. You can also add ranges of devices to be ignored by piping to /proc/cio_ignore; "add <device range>, <device range>, ..." will ignore the @@ -74,38 +72,54 @@ Command line parameters Note: While already known devices can be added to the list of devices to be ignored, there will be no effect on then. However, if such a device - disappears and then reappeares, it will then be ignored. + disappears and then reappears, it will then be ignored. To make + known devices go away, you need the "purge" command (see below). For example, "echo add 0.0.a000-0.0.accc, 0.0.af00-0.0.afff > /proc/cio_ignore" will add 0.0.a000-0.0.accc and 0.0.af00-0.0.afff to the list of ignored devices. - The devices can be specified either by bus id (0.0.abcd) or, for 2.4 backward - compatibilty, by the device number in hexadecimal (0xabcd or abcd). + You can remove already known but now ignored devices via + "echo purge > /proc/cio_ignore" + All devices ignored but still registered and not online (= not in use) + will be deregistered and thus removed from the system. + + The devices can be specified either by bus id (0.x.abcd) or, for 2.4 backward + compatibility, by the device number in hexadecimal (0xabcd or abcd). Device + numbers given as 0xabcd will be interpreted as 0.0.abcd. + +* /proc/cio_settle + + A write request to this file is blocked until all queued cio actions are + handled. This will allow userspace to wait for pending work affecting + device availability after changing cio_ignore or the hardware configuration. +* For some of the information present in the /proc filesystem in 2.4 (namely, + /proc/subchannels and /proc/chpids), see driver-model.txt. + Information formerly in /proc/irq_count is now in /proc/interrupts. -* /proc/s390dbf/cio_*/ (S/390 debug feature) + +debugfs entries +--------------- + +* /sys/kernel/debug/s390dbf/cio_*/ (S/390 debug feature) Some views generated by the debug feature to hold various debug outputs. - - /proc/s390dbf/cio_crw/sprintf + - /sys/kernel/debug/s390dbf/cio_crw/sprintf Messages from the processing of pending channel report words (machine check - handling), which will also show when CONFIG_DEBUG_CRW is defined. + handling). - - /proc/s390dbf/cio_msg/sprintf - Various debug messages from the common I/O-layer; generally, messages which - will also show when CONFIG_DEBUG_IO is defined. + - /sys/kernel/debug/s390dbf/cio_msg/sprintf + Various debug messages from the common I/O-layer. - - /proc/s390dbf/cio_trace/hex_ascii + - /sys/kernel/debug/s390dbf/cio_trace/hex_ascii Logs the calling of functions in the common I/O-layer and, if applicable, which subchannel they were called for, as well as dumps of some data structures (like irb in an error case). The level of logging can be changed to be more or less verbose by piping to - /proc/s390dbf/cio_*/level a number between 0 and 6; see the documentation on - the S/390 debug feature (Documentation/s390/s390dbf.txt) for details. - -* For some of the information present in the /proc filesystem in 2.4 (namely, - /proc/subchannels and /proc/chpids), see driver-model.txt. - Information formerly in /proc/irq_count is now in /proc/interrupts. + /sys/kernel/debug/s390dbf/cio_*/level a number between 0 and 6; see the + documentation on the S/390 debug feature (Documentation/s390/s390dbf.txt) + for details. diff --git a/Documentation/s390/Debugging390.txt b/Documentation/s390/Debugging390.txt index adbfe620c06..462321c1aee 100644 --- a/Documentation/s390/Debugging390.txt +++ b/Documentation/s390/Debugging390.txt @@ -7,9 +7,9 @@ Overview of Document: ===================== -This document is intended to give an good overview of how to debug -Linux for s/390 & z/Architecture it isn't intended as a complete reference & not a -tutorial on the fundamentals of C & assembly, it dosen't go into +This document is intended to give a good overview of how to debug +Linux for s/390 & z/Architecture. It isn't intended as a complete reference & not a +tutorial on the fundamentals of C & assembly. It doesn't go into 390 IO in any detail. It is intended to complement the documents in the reference section below & any other worthwhile references you get. @@ -41,7 +41,6 @@ ldd Debugging modules The proc file system Starting points for debugging scripting languages etc. -Dumptool & Lcrash SysRq References Special Thanks @@ -88,7 +87,7 @@ s/390 z/Architecture 0 0 Reserved ( must be 0 ) otherwise specification exception occurs. 1 1 Program Event Recording 1 PER enabled, - PER is used to facilititate debugging e.g. single stepping. + PER is used to facilitate debugging e.g. single stepping. 2-4 2-4 Reserved ( must be 0 ). @@ -163,7 +162,7 @@ s/390 z/Architecture 1 1 64 bit 32 1=31 bit addressing mode 0=24 bit addressing mode (for backward - compatibility ), linux always runs with this bit set to 1 + compatibility), linux always runs with this bit set to 1 33-64 Instruction address. 33-63 Reserved must be 0 @@ -188,7 +187,7 @@ Bytes 0-512 ( 200 hex ) on s/390 & 0-512,4096-4544,4604-5119 currently on z/Arch are used by the processor itself for holding such information as exception indications & entry points for exceptions. Bytes after 0xc00 hex are used by linux for per processor globals on s/390 & z/Architecture -( there is a gap on z/Architecure too currently between 0xc00 & 1000 which linux uses ). +( there is a gap on z/Architecture too currently between 0xc00 & 1000 which linux uses ). The closest thing to this on traditional architectures is the interrupt vector table. This is a good thing & does simplify some of the kernel coding however it means that we now cannot catch stray NULL pointers in the @@ -239,7 +238,7 @@ they go to 64 Bit. On 390 our limitations & strengths make us slightly different. For backward compatibility we are only allowed use 31 bits (2GB) -of our 32 bit addresses,however, we use entirely separate address +of our 32 bit addresses, however, we use entirely separate address spaces for the user & kernel. This means we can support 2GB of non Extended RAM on s/390, & more @@ -300,7 +299,7 @@ On z/Architecture our page indexes are now 2k in size but only mess with 2 segment indices each time we mess with a PMD. -3) As z/Architecture supports upto a massive 5-level page table lookup we +3) As z/Architecture supports up to a massive 5-level page table lookup we can only use 3 currently on Linux ( as this is all the generic kernel currently supports ) however this may change in future this allows us to access ( according to my sums ) @@ -317,9 +316,9 @@ Each process/thread under Linux for S390 has its own kernel task_struct defined in linux/include/linux/sched.h The S390 on initialisation & resuming of a process on a cpu sets the __LC_KERNEL_STACK variable in the spare prefix area for this cpu -( which we use for per processor globals). +(which we use for per-processor globals). -The kernel stack pointer is intimately tied with the task stucture for +The kernel stack pointer is intimately tied with the task structure for each processor as follows. s/390 @@ -354,7 +353,7 @@ static inline struct task_struct * get_current(void) } i.e. just anding the current kernel stack pointer with the mask -8192. -Thankfully because Linux dosen't have support for nested IO interrupts +Thankfully because Linux doesn't have support for nested IO interrupts & our devices have large buffers can survive interrupts being shut for short amounts of time we don't need a separate stack for interrupts. @@ -366,8 +365,8 @@ Register Usage & Stackframes on Linux for s/390 & z/Architecture Overview: --------- This is the code that gcc produces at the top & the bottom of -each function, it usually is fairly consistent & similar from -function to function & if you know its layout you can probalby +each function. It usually is fairly consistent & similar from +function to function & if you know its layout you can probably make some headway in finding the ultimate cause of a problem after a crash without a source level debugger. @@ -394,7 +393,7 @@ i.e they aren't in registers & they aren't static. back-chain: This is a pointer to the stack pointer before entering a framed functions ( see frameless function ) prologue got by -deferencing the address of the current stack pointer, +dereferencing the address of the current stack pointer, i.e. got by accessing the 32 bit value at the stack pointers current location. @@ -480,7 +479,7 @@ r2 argument 0 / return value 0 call-clobbered r3 argument 1 / return value 1 (if long long) call-clobbered r4 argument 2 call-clobbered r5 argument 3 call-clobbered -r6 argument 5 saved +r6 argument 4 saved r7 pointer-to arguments 5 to ... saved r8 this & that saved r9 this & that saved @@ -502,7 +501,7 @@ Notes: ------ 1) The only requirement is that registers which are used by the callee are saved, e.g. the compiler is perfectly -capible of using r11 for purposes other than a frame a +capable of using r11 for purposes other than a frame a frame pointer if a frame pointer is not needed. 2) In functions with variable arguments e.g. printf the calling procedure is identical to one without variable arguments & the same number of @@ -724,7 +723,7 @@ This is useful for debugging because 1) You can double check whether the files you expect to be included are the ones that are being included ( e.g. double check that you aren't going to the i386 asm directory ). 2) Check that macro definitions aren't clashing with typedefs, -3) Check that definitons aren't being used before they are being included. +3) Check that definitions aren't being used before they are being included. 4) Helps put the line emitting the error under the microscope if it contains macros. For convenience the Linux kernel's makefile will do preprocessing automatically for you @@ -840,14 +839,13 @@ using the strip command to make it a more reasonable size to boot it. A source/assembly mixed dump of the kernel can be done with the line objdump --source vmlinux > vmlinux.lst -Also if the file isn't compiled -g this will output as much debugging information -as it can ( e.g. function names ), however, this is very slow as it spends lots -of time searching for debugging info, the following self explanitory line should be used -instead if the code isn't compiled -g. +Also, if the file isn't compiled -g, this will output as much debugging information +as it can (e.g. function names). This is very slow as it spends lots +of time searching for debugging info. The following self explanatory line should be used +instead if the code isn't compiled -g, as it is much faster: objdump --disassemble-all --syms vmlinux > vmlinux.lst -as it is much faster -As hard drive space is valuble most of us use the following approach. +As hard drive space is valuable most of us use the following approach. 1) Look at the emitted psw on the console to find the crash address in the kernel. 2) Look at the file System.map ( in the linux directory ) produced when building the kernel to find the closest address less than the current PSW to find the @@ -861,7 +859,7 @@ Linux source tree. 6) rm /arch/s390/kernel/signal.o 7) make /arch/s390/kernel/signal.o 8) watch the gcc command line emitted -9) type it in again or alernatively cut & paste it on the console adding the -g option. +9) type it in again or alternatively cut & paste it on the console adding the -g option. 10) objdump --source arch/s390/kernel/signal.o > signal.lst This will output the source & the assembly intermixed, as the snippet below shows This will unfortunately output addresses which aren't the same @@ -871,7 +869,7 @@ by playing with the --adjust-vma parameter to objdump. -extern inline void spin_lock(spinlock_t *lp) +static inline void spin_lock(spinlock_t *lp) { a0: 18 34 lr %r3,%r4 a2: a7 3a 03 bc ahi %r3,956 @@ -903,7 +901,7 @@ A. It is a tool for intercepting calls to the kernel & logging them to a file & on the screen. Q. What use is it ? -A. You can used it to find out what files a particular program opens. +A. You can use it to find out what files a particular program opens. @@ -912,9 +910,9 @@ Example 1 If you wanted to know does ping work but didn't have the source strace ping -c 1 127.0.0.1 & then look at the man pages for each of the syscalls below, -( In fact this is sometimes easier than looking at some spagetti -source which conditionally compiles for several architectures ) -Not everything that it throws out needs to make sense immeadiately +( In fact this is sometimes easier than looking at some spaghetti +source which conditionally compiles for several architectures ). +Not everything that it throws out needs to make sense immediately. Just looking quickly you can see that it is making up a RAW socket for the ICMP protocol. @@ -974,8 +972,9 @@ through the pipe for each line containing the string open. Example 3 --------- -Getting sophistocated -telnetd crashes on & I don't know why +Getting sophisticated +telnetd crashes & I don't know why + Steps ----- 1) Replace the following line in /etc/inetd.conf @@ -1037,7 +1036,7 @@ e.g. man strace, man alarm, man socket. Performance Debugging ===================== -gcc is capible of compiling in profiling code just add the -p option +gcc is capable of compiling in profiling code just add the -p option to the CFLAGS, this obviously affects program size & performance. This can be used by the gprof gnu profiling tool or the gcov the gnu code coverage tool ( code coverage is a means of testing @@ -1085,8 +1084,7 @@ Notes ----- Addresses & values in the VM debugger are always hex never decimal Address ranges are of the format <HexValue1>-<HexValue2> or <HexValue1>.<HexValue2> -e.g. The address range 0x2000 to 0x3000 can be described described as -2000-3000 or 2000.1000 +e.g. The address range 0x2000 to 0x3000 can be described as 2000-3000 or 2000.1000 The VM Debugger is case insensitive. @@ -1311,7 +1309,7 @@ for finding out when a particular variable changes. An alternative way of finding the STD of a currently running process is to do the following, ( this method is more complex but -could be quite convient if you aren't updating the kernel much & +could be quite convenient if you aren't updating the kernel much & so your kernel structures will stay constant for a reasonable period of time ). @@ -1403,7 +1401,7 @@ Syscalls are implemented on Linux for S390 by the Supervisor call instruction (S possibilities of these as the instruction is made up of a 0xA opcode & the second byte being the syscall number. They are traced using the simple command. TR SVC <Optional value or range> -the syscalls are defined in linux/include/asm-s390/unistd.h +the syscalls are defined in linux/arch/s390/include/asm/unistd.h e.g. to trace all file opens just do TR SVC 5 ( as this is the syscall number of open ) @@ -1413,14 +1411,14 @@ SMP Specific commands To find out how many cpus you have Q CPUS displays all the CPU's available to your virtual machine To find the cpu that the current cpu VM debugger commands are being directed at do -Q CPU to change the current cpu cpu VM debugger commands are being directed at do +Q CPU to change the current cpu VM debugger commands are being directed at do CPU <desired cpu no> On a SMP guest issue a command to all CPUs try prefixing the command with cpu all. To issue a command to a particular cpu try cpu <cpu number> e.g. CPU 01 TR I R 2000.3000 If you are running on a guest with several cpus & you have a IO related problem -& cannot follow the flow of code but you know it isnt smp related. +& cannot follow the flow of code but you know it isn't smp related. from the bash prompt issue shutdown -h now or halt. do a Q CPUS to find out how many cpus you have @@ -1603,7 +1601,7 @@ V000FFFD0 00010400 80010802 8001085A 000FFFA0 our 3rd return address is 8001085A as the 04B52002 looks suspiciously like rubbish it is fair to assume that the kernel entry routines -for the sake of optimisation dont set up a backchain. +for the sake of optimisation don't set up a backchain. now look at System.map to see if the addresses make any sense. @@ -1639,11 +1637,11 @@ more useful information. Unlike other bus architectures modern 390 systems do their IO using mostly fibre optics & devices such as tapes & disks can be shared between several mainframes, -also S390 can support upto 65536 devices while a high end PC based system might be choking +also S390 can support up to 65536 devices while a high end PC based system might be choking with around 64. Here is some of the common IO terminology Subchannel: -This is the logical number most IO commands use to talk to an IO device there can be upto +This is the logical number most IO commands use to talk to an IO device there can be up to 0x10000 (65536) of these in a configuration typically there is a few hundred. Under VM for simplicity they are allocated contiguously, however on the native hardware they are not they typically stay consistent between boots provided no new hardware is inserted or removed. @@ -1652,7 +1650,7 @@ HALT SUBCHANNEL,MODIFY SUBCHANNEL,RESUME SUBCHANNEL,START SUBCHANNEL,STORE SUBCH TEST SUBCHANNEL ) we use this as the ID of the device we wish to talk to, the most important of these instructions are START SUBCHANNEL ( to start IO ), TEST SUBCHANNEL ( to check whether the IO completed successfully ), & HALT SUBCHANNEL ( to kill IO ), a subchannel -can have up to 8 channel paths to a device this offers redunancy if one is not available. +can have up to 8 channel paths to a device this offers redundancy if one is not available. Device Number: @@ -1660,7 +1658,7 @@ This number remains static & Is closely tied to the hardware, there are 65536 of also they are made up of a CHPID ( Channel Path ID, the most significant 8 bits ) & another lsb 8 bits. These remain static even if more devices are inserted or removed from the hardware, there is a 1 to 1 mapping between Subchannels & Device Numbers provided -devices arent inserted or removed. +devices aren't inserted or removed. Channel Control Words: CCWS are linked lists of instructions initially pointed to by an operation request block (ORB), @@ -1674,8 +1672,8 @@ channel is idle & the second for device end ( secondary status ) sometimes you g concurrently, you check how the IO went on by issuing a TEST SUBCHANNEL at each interrupt, from which you receive an Interruption response block (IRB). If you get channel & device end status in the IRB without channel checks etc. your IO probably went okay. If you didn't you -probably need a doctorto examine the IRB & extended status word etc. -If an error occurs more sophistocated control units have a facitity known as +probably need a doctor to examine the IRB & extended status word etc. +If an error occurs, more sophisticated control units have a facility known as concurrent sense this means that if an error occurs Extended sense information will be presented in the Extended status word in the IRB if not you have to issue a subsequent SENSE CCW command after the test subchannel. @@ -1704,7 +1702,7 @@ concentrate on data processing. IOP's can use one or more links ( known as channel paths ) to talk to each IO device. It first checks for path availability & chooses an available one, then starts ( & sometimes terminates IO ). -There are two types of channel path ESCON & the Paralell IO interface. +There are two types of channel path: ESCON & the Parallel IO interface. IO devices are attached to control units, control units provide the logic to interface the channel paths & channel path IO protocols to @@ -1743,14 +1741,14 @@ controllers or a control unit which connects to 1000 3270 terminals ). The 390 IO systems come in 2 flavours the current 390 machines support both -The Older 360 & 370 Interface,sometimes called the paralell I/O interface, +The Older 360 & 370 Interface,sometimes called the Parallel I/O interface, sometimes called Bus-and Tag & sometimes Original Equipment Manufacturers Interface (OEMI). -This byte wide paralell channel path/bus has parity & data on the "Bus" cable +This byte wide Parallel channel path/bus has parity & data on the "Bus" cable & control lines on the "Tag" cable. These can operate in byte multiplex mode for sharing between several slow devices or burst mode & monopolize the channel for the -whole burst. Upto 256 devices can be addressed on one of these cables. These cables are +whole burst. Up to 256 devices can be addressed on one of these cables. These cables are about one inch in diameter. The maximum unextended length supported by these cables is 125 Meters but this can be extended up to 2km with a fibre optic channel extended such as a 3044. The maximum burst speed supported is 4.5 megabytes per second however @@ -1760,7 +1758,7 @@ One of these paths can be daisy chained to up to 8 control units. ESCON if fibre optic it is also called FICON Was introduced by IBM in 1990. Has 2 fibre optic cables & uses either leds or lasers -for communication at a signaling rate of upto 200 megabits/sec. As 10bits are transferred +for communication at a signaling rate of up to 200 megabits/sec. As 10bits are transferred for every 8 bits info this drops to 160 megabits/sec & to 18.6 Megabytes/sec once control info & CRC are added. ESCON only operates in burst mode. @@ -1768,7 +1766,7 @@ ESCONs typical max cable length is 3km for the led version & 20km for the laser known as XDF ( extended distance facility ). This can be further extended by using an ESCON director which triples the above mentioned ranges. Unlike Bus & Tag as ESCON is serial it uses a packet switching architecture the standard Bus & Tag control protocol -is however present within the packets. Upto 256 devices can be attached to each control +is however present within the packets. Up to 256 devices can be attached to each control unit that uses one of these interfaces. Common 390 Devices include: @@ -1777,7 +1775,7 @@ Consoles 3270 & 3215 ( a teletype emulated under linux for a line mode console ) DASD's direct access storage devices ( otherwise known as hard disks ). Tape Drives. CTC ( Channel to Channel Adapters ), -ESCON or Paralell Cables used as a very high speed serial link +ESCON or Parallel Cables used as a very high speed serial link between 2 machines. We use 2 cables under linux to do a bi-directional serial link. @@ -1803,8 +1801,8 @@ OSA 7C09 ON OSA 7C09 SUBCHANNEL = 0001 OSA 7C14 ON OSA 7C14 SUBCHANNEL = 0002 OSA 7C15 ON OSA 7C15 SUBCHANNEL = 0003 -If you have a guest with certain priviliges you may be able to see devices -which don't belong to you to avoid this do add the option V. +If you have a guest with certain privileges you may be able to see devices +which don't belong to you. To avoid this, add the option V. e.g. Q V OSA @@ -1837,7 +1835,7 @@ RDRLIST RECEIVE / LOG TXT A1 ( replace 8) filel & press F11 to look at it -You should see someting like. +You should see something like: 00020942' SSCH B2334000 0048813C CC 0 SCH 0000 DEV 7C08 CPA 000FFDF0 PARM 00E2C9C4 KEY 0 FPI C0 LPM 80 @@ -1916,7 +1914,7 @@ Assembly -------- info registers: displays registers other than floating point. info all-registers: displays floating points as well. -disassemble: dissassembles +disassemble: disassembles e.g. disassemble without parameters will disassemble the current function disassemble $pc $pc+10 @@ -1935,7 +1933,7 @@ undisplay : undo's display's info breakpoints: shows all current breakpoints -info stack: shows stack back trace ( if this dosent work too well, I'll show you the +info stack: shows stack back trace ( if this doesn't work too well, I'll show you the stacktrace by hand below ). info locals: displays local variables. @@ -1985,7 +1983,7 @@ break *$pc break *0x400618 -heres a really useful one for large programs +Here's a really useful one for large programs rbr Set a breakpoint for all functions matching REGEXP e.g. @@ -2045,13 +2043,13 @@ what gdb does when the victim receives certain signals. list: e.g. list lists current function source -list 1,10 list first 10 lines of curret file. +list 1,10 list first 10 lines of current file. list test.c:1,10 directory: Adds directories to be searched for source if gdb cannot find the source. -(note it is a bit sensititive about slashes ) +(note it is a bit sensitive about slashes) e.g. To add the root of the filesystem to the searchpath do directory // @@ -2123,9 +2121,9 @@ p/x (*(**$sp+56))&0x7fffffff Disassembling instructions without debug info --------------------------------------------- -gdb typically compains if there is a lack of debugging -symbols in the disassemble command with -"No function contains specified address." to get around +gdb typically complains if there is a lack of debugging +symbols in the disassemble command with +"No function contains specified address." To get around this do x/<number lines to disassemble>xi <address> e.g. @@ -2153,7 +2151,7 @@ program as if it just crashed on your system, it is usually called core & create current working directory. This is very useful in that a customer can mail a core dump to a technical support department & the technical support department can reconstruct what happened. -Provided the have an identical copy of this program with debugging symbols compiled in & +Provided they have an identical copy of this program with debugging symbols compiled in & the source base of this build is available. In short it is far more useful than something like a crash log could ever hope to be. @@ -2184,7 +2182,7 @@ ps -aux | grep gdb kill -SIGSEGV <gdb's pid> or alternatively use killall -SIGSEGV gdb if you have the killall command. Now look at the core dump. -./gdb ./gdb core +./gdb core Displays the following GNU gdb 4.18 Copyright 1998 Free Software Foundation, Inc. @@ -2210,9 +2208,9 @@ Breakpoint 2 at 0x4d87a4: file top.c, line 2609. #3 0x5167e6 in readline_internal_char () at readline.c:454 #4 0x5168ee in readline_internal_charloop () at readline.c:507 #5 0x51692c in readline_internal () at readline.c:521 -#6 0x5164fe in readline (prompt=0x7ffff810 "\177x\177\177x") +#6 0x5164fe in readline (prompt=0x7ffff810 "\177ÿøx\177ÿ÷Ø\177ÿøxÀ") at readline.c:349 -#7 0x4d7a8a in command_line_input (prrompt=0x564420 "(gdb) ", repeat=1, +#7 0x4d7a8a in command_line_input (prompt=0x564420 "(gdb) ", repeat=1, annotation_suffix=0x4d6b44 "prompt") at top.c:2091 #8 0x4d6cf0 in command_loop () at top.c:1345 #9 0x4e25bc in main (argc=1, argv=0x7ffffdf4) at main.c:635 @@ -2274,7 +2272,7 @@ IP forwarding is on. There is a lot of useful info in here best found by going in & having a look around, so I'll take you through some entries I consider important. -All the processes running on the machine have there own entry defined by +All the processes running on the machine have their own entry defined by /proc/<pid> So lets have a look at the init process cd /proc/1 @@ -2316,7 +2314,7 @@ Showing us the shared libraries init uses where they are in memory /proc/1/mem is the current running processes memory which you can read & write to like a file. strace uses this sometimes as it is a bit faster than the -rather inefficent ptrace interface for peeking at DATA. +rather inefficient ptrace interface for peeking at DATA. cat status @@ -2446,7 +2444,7 @@ displays the following lines as it executes them. + RELSTATUS=release + MACHTYPE=i586-pc-linux-gnu -perl -d <scriptname> runs the perlscript in a fully intercative debugger +perl -d <scriptname> runs the perlscript in a fully interactive debugger <like gdb>. Type 'h' in the debugger for help. @@ -2456,39 +2454,6 @@ jdb <filename> another fully interactive gdb style debugger. -Dumptool & Lcrash ( lkcd ) -========================== -Michael Holzheu & others here at IBM have a fairly mature port of -SGI's lcrash tool which allows one to look at kernel structures in a -running kernel. - -It also complements a tool called dumptool which dumps all the kernel's -memory pages & registers to either a tape or a disk. -This can be used by tech support or an ambitious end user do -post mortem debugging of a machine like gdb core dumps. - -Going into how to use this tool in detail will be explained -in other documentation supplied by IBM with the patches & the -lcrash homepage http://oss.sgi.com/projects/lkcd/ & the lcrash manpage. - -How they work -------------- -Lcrash is a perfectly normal program,however, it requires 2 -additional files, Kerntypes which is built using a patch to the -linux kernel sources in the linux root directory & the System.map. - -Kerntypes is an an objectfile whose sole purpose in life -is to provide stabs debug info to lcrash, to do this -Kerntypes is built from kerntypes.c which just includes the most commonly -referenced header files used when debugging, lcrash can then read the -.stabs section of this file. - -Debugging a live system it uses /dev/mem -alternatively for post mortem debugging it uses the data -collected by dumptool. - - - SysRq ===== This is now supported by linux for s/390 & z/Architecture. @@ -2532,5 +2497,5 @@ Special Thanks ============== Special thanks to Neale Ferguson who maintains a much prettier HTML version of this page at -http://penguinvm.princeton.edu/notes.html#Debug390 +http://linuxvm.org/penguinvm/ Bob Grainger Stefan Bader & others for reporting bugs diff --git a/Documentation/s390/TAPE b/Documentation/s390/TAPE deleted file mode 100644 index c639aa5603f..00000000000 --- a/Documentation/s390/TAPE +++ /dev/null @@ -1,122 +0,0 @@ -Channel attached Tape device driver - ------------------------------WARNING----------------------------------------- -This driver is considered to be EXPERIMENTAL. Do NOT use it in -production environments. Feel free to test it and report problems back to us. ------------------------------------------------------------------------------ - -The LINUX for zSeries tape device driver manages channel attached tape drives -which are compatible to IBM 3480 or IBM 3490 magnetic tape subsystems. This -includes various models of these devices (for example the 3490E). - - -Tape driver features - -The device driver supports a maximum of 128 tape devices. -No official LINUX device major number is assigned to the zSeries tape device -driver. It allocates major numbers dynamically and reports them on system -startup. -Typically it will get major number 254 for both the character device front-end -and the block device front-end. - -The tape device driver needs no kernel parameters. All supported devices -present are detected on driver initialization at system startup or module load. -The devices detected are ordered by their subchannel numbers. The device with -the lowest subchannel number becomes device 0, the next one will be device 1 -and so on. - - -Tape character device front-end - -The usual way to read or write to the tape device is through the character -device front-end. The zSeries tape device driver provides two character devices -for each physical device -- the first of these will rewind automatically when -it is closed, the second will not rewind automatically. - -The character device nodes are named /dev/rtibm0 (rewinding) and /dev/ntibm0 -(non-rewinding) for the first device, /dev/rtibm1 and /dev/ntibm1 for the -second, and so on. - -The character device front-end can be used as any other LINUX tape device. You -can write to it and read from it using LINUX facilities such as GNU tar. The -tool mt can be used to perform control operations, such as rewinding the tape -or skipping a file. - -Most LINUX tape software should work with either tape character device. - - -Tape block device front-end - -The tape device may also be accessed as a block device in read-only mode. -This could be used for software installation in the same way as it is used with -other operation systems on the zSeries platform (and most LINUX -distributions are shipped on compact disk using ISO9660 filesystems). - -One block device node is provided for each physical device. These are named -/dev/btibm0 for the first device, /dev/btibm1 for the second and so on. -You should only use the ISO9660 filesystem on LINUX for zSeries tapes because -the physical tape devices cannot perform fast seeks and the ISO9660 system is -optimized for this situation. - - -Tape block device example - -In this example a tape with an ISO9660 filesystem is created using the first -tape device. ISO9660 filesystem support must be built into your system kernel -for this. -The mt command is used to issue tape commands and the mkisofs command to -create an ISO9660 filesystem: - -- create a LINUX directory (somedir) with the contents of the filesystem - mkdir somedir - cp contents somedir - -- insert a tape - -- ensure the tape is at the beginning - mt -f /dev/ntibm0 rewind - -- set the blocksize of the character driver. The blocksize 2048 bytes - is commonly used on ISO9660 CD-Roms - mt -f /dev/ntibm0 setblk 2048 - -- write the filesystem to the character device driver - mkisofs -o /dev/ntibm0 somedir - -- rewind the tape again - mt -f /dev/ntibm0 rewind - -- Now you can mount your new filesystem as a block device: - mount -t iso9660 -o ro,block=2048 /dev/btibm0 /mnt - -TODO List - - - Driver has to be stabilized still - -BUGS - -This driver is considered BETA, which means some weaknesses may still -be in it. -If an error occurs which cannot be handled by the code you will get a -sense-data dump.In that case please do the following: - -1. set the tape driver debug level to maximum: - echo 6 >/proc/s390dbf/tape/level - -2. re-perform the actions which produced the bug. (Hopefully the bug will - reappear.) - -3. get a snapshot from the debug-feature: - cat /proc/s390dbf/tape/hex_ascii >somefile - -4. Now put the snapshot together with a detailed description of the situation - that led to the bug: - - Which tool did you use? - - Which hardware do you have? - - Was your tape unit online? - - Is it a shared tape unit? - -5. Send an email with your bug report to: - mailto:Linux390@de.ibm.com - - diff --git a/Documentation/s390/cds.txt b/Documentation/s390/cds.txt index f0be389c711..480a78ef5a1 100644 --- a/Documentation/s390/cds.txt +++ b/Documentation/s390/cds.txt @@ -51,13 +51,8 @@ The major changes are: * The interrupt handlers must be adapted to use a ccw_device as argument. Moreover, they don't return a devstat, but an irb. * Before initiating an io, the options must be set via ccw_device_set_options(). - -read_dev_chars() - read device characteristics - -read_conf_data() -read_conf_data_lpm() - read configuration data. +* Instead of calling read_dev_chars()/read_conf_data(), the driver issues + the channel program and handles the interrupt itself. ccw_device_get_ciw() get commands from extended sense data. @@ -98,12 +93,12 @@ The following chapters describe the I/O related interface routines the Linux/390 common device support (CDS) provides to allow for device specific driver implementations on the IBM ESA/390 hardware platform. Those interfaces intend to provide the functionality required by every device driver -implementaion to allow to drive a specific hardware device on the ESA/390 +implementation to allow to drive a specific hardware device on the ESA/390 platform. Some of the interface routines are specific to Linux/390 and some of them can be found on other Linux platforms implementations too. Miscellaneous function prototypes, data declarations, and macro definitions can be found in the architecture specific C header file -linux/include/asm-s390/irq.h. +linux/arch/s390/include/asm/irq.h. Overview of CDS interface concepts @@ -114,7 +109,7 @@ the ESA/390 architecture has implemented a so called channel subsystem, that provides a unified view of the devices physically attached to the systems. Though the ESA/390 hardware platform knows about a huge variety of different peripheral attachments like disk devices (aka. DASDs), tapes, communication -controllers, etc. they can all by accessed by a well defined access method and +controllers, etc. they can all be accessed by a well defined access method and they are presenting I/O completion a unified way : I/O interruptions. Every single device is uniquely identified to the system by a so called subchannel, where the ESA/390 architecture allows for 64k devices be attached. @@ -130,11 +125,6 @@ present their hardware status by the same (shared) IRQ, the operating system has to call every single device driver registered on this IRQ in order to determine the device driver owning the device that raised the interrupt. -In order not to introduce a new I/O concept to the common Linux code, -Linux/390 preserves the IRQ concept and semantically maps the ESA/390 -subchannels to Linux as IRQs. This allows Linux/390 to support up to 64k -different IRQs, uniquely representig a single device each. - Up to kernel 2.4, Linux/390 used to provide interfaces via the IRQ (subchannel). For internal use of the common I/O layer, these are still there. However, device drivers should use the new calling interface via the ccw_device only. @@ -143,7 +133,7 @@ During its startup the Linux/390 system checks for peripheral devices. Each of those devices is uniquely defined by a so called subchannel by the ESA/390 channel subsystem. While the subchannel numbers are system generated, each subchannel also takes a user defined attribute, the so called device number. -Both subchannel number and device number can not exceed 65535. During driverfs +Both subchannel number and device number cannot exceed 65535. During sysfs initialisation, the information about control unit type and device types that imply specific I/O commands (channel command words - CCWs) in order to operate the device are gathered. Device drivers can retrieve this set of hardware @@ -151,9 +141,8 @@ information during their initialization step to recognize the devices they support using the information saved in the struct ccw_device given to them. This methods implies that Linux/390 doesn't require to probe for free (not armed) interrupt request lines (IRQs) to drive its devices with. Where -applicable, the device drivers can use the read_dev_chars() to retrieve device -characteristics. This can be done without having to request device ownership -previously. +applicable, the device drivers can use issue the READ DEVICE CHARACTERISTICS +ccw to retrieve device characteristics in its online routine. In order to allow for easy I/O initiation the CDS layer provides a ccw_device_start() interface that takes a device specific channel program (one @@ -170,73 +159,6 @@ SUBCHANNEL (HSCH) command without having pending I/O requests. This function is also covered by ccw_device_halt(). -read_dev_chars() - Read Device Characteristics - -This routine returns the characteristics for the device specified. - -The function is meant to be called with an irq handler in place; that is, -at earliest during set_online() processing. - -While the request is procesed synchronously, the device interrupt -handler is called for final ending status. In case of error situations the -interrupt handler may recover appropriately. The device irq handler can -recognize the corresponding interrupts by the interruption parameter be -0x00524443.The ccw_device must not be locked prior to calling read_dev_chars(). - -The function may be called enabled or disabled. - -int read_dev_chars(struct ccw_device *cdev, void **buffer, int length ); - -cdev - the ccw_device the information is requested for. -buffer - pointer to a buffer pointer. The buffer pointer itself - must contain a valid buffer area. -length - length of the buffer provided. - -The read_dev_chars() function returns : - - 0 - successful completion --ENODEV - cdev invalid --EINVAL - an invalid parameter was detected, or the function was called early. --EBUSY - an irrecoverable I/O error occurred or the device is not - operational. - - -read_conf_data(), read_conf_data_lpm() - Read Configuration Data - -Retrieve the device dependent configuration data. Please have a look at your -device dependent I/O commands for the device specific layout of the node -descriptor elements. read_conf_data_lpm() will retrieve the configuration data -for a specific path. - -The function is meant to be called with the device already enabled; that is, -at earliest during set_online() processing. - -The function may be called enabled or disabled, but the device must not be -locked - -int read_conf_data(struct ccw_device, void **buffer, int *length); -int read_conf_data_lpm(struct ccw_device, void **buffer, int *length, __u8 lpm); - -cdev - the ccw_device the data is requested for. -buffer - Pointer to a buffer pointer. The read_conf_data() routine - will allocate a buffer and initialize the buffer pointer - accordingly. It's the device driver's responsibility to - release the kernel memory if no longer needed. -length - Length of the buffer allocated and retrieved. -lpm - Logical path mask to be used for retrieving the data. If - zero the data is retrieved on the next path available. - -The read_conf_data() function returns : - 0 - Successful completion --ENODEV - cdev invalid. --EINVAL - An invalid parameter was detected, or the function was called early. --EIO - An irrecoverable I/O error occurred or the device is - not operational. --ENOMEM - The read_conf_data() routine couldn't obtain storage. --EOPNOTSUPP - The device doesn't support the read configuration - data command. - - get_ciw() - get command information word This call enables a device driver to get information about supported commands @@ -325,7 +247,7 @@ with the following CCW flags values defined : CCW_FLAG_DC - data chaining CCW_FLAG_CC - command chaining -CCW_FLAG_SLI - suppress incorrct length +CCW_FLAG_SLI - suppress incorrect length CCW_FLAG_SKIP - skip CCW_FLAG_PCI - PCI CCW_FLAG_IDA - indirect addressing @@ -342,13 +264,13 @@ DOIO_REPORT_ALL - report all interrupt conditions The ccw_device_start() function returns : 0 - successful completion or request successfully initiated --EBUSY - The device is currently processing a previous I/O request, or ther is +-EBUSY - The device is currently processing a previous I/O request, or there is a status pending at the device. -ENODEV - cdev is invalid, the device is not operational or the ccw_device is not online. When the I/O request completes, the CDS first level interrupt handler will -accumalate the status in a struct irb and then call the device interrupt handler. +accumulate the status in a struct irb and then call the device interrupt handler. The intparm field will contain the value the device driver has associated with a particular I/O request. If a pending device status was recognized, intparm will be set to 0 (zero). This may happen during I/O initiation or delayed @@ -364,10 +286,10 @@ first: timeout value -EIO: the common I/O layer terminated the request due to an error state -If the concurrent sense flag in the extended status word in the irb is set, the -field irb->scsw.count describes the numer of device specific sense bytes -available in the extended control word irb->scsw.ecw[0]. No device sensing by -the device driver itself is required. +If the concurrent sense flag in the extended status word (esw) in the irb is +set, the field erw.scnt in the esw describes the number of device specific +sense bytes available in the extended control word irb->scsw.ecw[]. No device +sensing by the device driver itself is required. The device interrupt handler can use the following definitions to investigate the primary unit check source coded in sense byte 0 : @@ -410,30 +332,11 @@ individual flag meanings. Usage Notes : -Prior to call ccw_device_start() the device driver must assure disabled state, -i.e. the I/O mask value in the PSW must be disabled. This can be accomplished -by calling local_save_flags( flags). The current PSW flags are preserved and -can be restored by local_irq_restore( flags) at a later time. - -If the device driver violates this rule while running in a uni-processor -environment an interrupt might be presented prior to the ccw_device_start() -routine returning to the device driver main path. In this case we will end in a -deadlock situation as the interrupt handler will try to obtain the irq -lock the device driver still owns (see below) ! - -The driver must assure to hold the device specific lock. This can be -accomplished by - -(i) spin_lock(get_ccwdev_lock(cdev)), or -(ii) spin_lock_irqsave(get_ccwdev_lock(cdev), flags) - -Option (i) should be used if the calling routine is running disabled for -I/O interrupts (see above) already. Option (ii) obtains the device gate und -puts the CPU into I/O disabled state by preserving the current PSW flags. +ccw_device_start() must be called disabled and with the ccw device lock held. The device driver is allowed to issue the next ccw_device_start() call from within its interrupt handler already. It is not required to schedule a -bottom-half, unless an non deterministicly long running error recovery procedure +bottom-half, unless a non deterministically long running error recovery procedure or similar needs to be scheduled. During I/O processing the Linux/390 generic I/O device driver support has already obtained the IRQ lock, i.e. the handler must not try to obtain it again when calling ccw_device_start() or we end in a @@ -454,7 +357,7 @@ information prior to device-end the device driver urgently relies on. In this case all I/O interruptions are presented to the device driver until final status is recognized. -If a device is able to recover from asynchronosly presented I/O errors, it can +If a device is able to recover from asynchronously presented I/O errors, it can perform overlapping I/O using the DOIO_EARLY_NOTIFICATION flag. While some devices always report channel-end and device-end together, with a single interrupt, others present primary status (channel-end) when the channel is @@ -488,7 +391,7 @@ int ccw_device_resume(struct ccw_device *cdev); cdev - ccw_device the resume operation is requested for -The resume_IO() function returns: +The ccw_device_resume() function returns: 0 - suspended channel program is resumed -EBUSY - status pending @@ -507,6 +410,8 @@ a long-running channel program or the device might require to initially issue a halt subchannel (HSCH) I/O command. For those purposes the ccw_device_halt() command is provided. +ccw_device_halt() must be called disabled and with the ccw device lock held. + int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm); @@ -517,7 +422,7 @@ intparm : interruption parameter; value is only used if no I/O The ccw_device_halt() function returns : - 0 - successful completion or request successfully initiated + 0 - request successfully initiated -EBUSY - the device is currently busy, or status pending. -ENODEV - cdev invalid. -EINVAL - The device is not operational or the ccw device is not online. @@ -533,6 +438,23 @@ can then perform an appropriate action. Prior to interrupt of an outstanding read to a network device (with or without PCI flag) a ccw_device_halt() is required to end the pending operation. +ccw_device_clear() - Terminage I/O Request Processing + +In order to terminate all I/O processing at the subchannel, the clear subchannel +(CSCH) command is used. It can be issued via ccw_device_clear(). + +ccw_device_clear() must be called disabled and with the ccw device lock held. + +int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm); + +cdev: ccw_device the clear operation is requested for +intparm: interruption parameter (see ccw_device_halt()) + +The ccw_device_clear() function returns: + + 0 - request successfully initiated +-ENODEV - cdev invalid +-EINVAL - The device is not operational or the ccw device is not online. Miscellaneous Support Routines diff --git a/Documentation/s390/crypto/crypto-API.txt b/Documentation/s390/crypto/crypto-API.txt deleted file mode 100644 index 78a77624a71..00000000000 --- a/Documentation/s390/crypto/crypto-API.txt +++ /dev/null @@ -1,83 +0,0 @@ -crypto-API support for z990 Message Security Assist (MSA) instructions -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -AUTHOR: Thomas Spatzier (tspat@de.ibm.com) - - -1. Introduction crypto-API -~~~~~~~~~~~~~~~~~~~~~~~~~~ -See Documentation/crypto/api-intro.txt for an introduction/description of the -kernel crypto API. -According to api-intro.txt support for z990 crypto instructions has been added -in the algorithm api layer of the crypto API. Several files containing z990 -optimized implementations of crypto algorithms are placed in the -arch/s390/crypto directory. - - -2. Probing for availability of MSA -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -It should be possible to use Kernels with the z990 crypto implementations both -on machines with MSA available an on those without MSA (pre z990 or z990 -without MSA). Therefore a simple probing mechanisms has been implemented: -In the init function of each crypto module the availability of MSA and of the -respective crypto algorithm in particular will be tested. If the algorithm is -available the module will load and register its algorithm with the crypto API. - -If the respective crypto algorithm is not available, the init function will -return -ENOSYS. In that case a fallback to the standard software implementation -of the crypto algorithm must be taken ( -> the standard crypto modules are -also build when compiling the kernel). - - -3. Ensuring z990 crypto module preference -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -If z990 crypto instructions are available the optimized modules should be -preferred instead of standard modules. - -3.1. compiled-in modules -~~~~~~~~~~~~~~~~~~~~~~~~ -For compiled-in modules it has to be ensured that the z990 modules are linked -before the standard crypto modules. Then, on system startup the init functions -of z990 crypto modules will be called first and query for availability of z990 -crypto instructions. If instruction is available, the z990 module will register -its crypto algorithm implementation -> the load of the standard module will fail -since the algorithm is already registered. -If z990 crypto instruction is not available the load of the z990 module will -fail -> the standard module will load and register its algorithm. - -3.2. dynamic modules -~~~~~~~~~~~~~~~~~~~~ -A system administrator has to take care of giving preference to z990 crypto -modules. If MSA is available appropriate lines have to be added to -/etc/modprobe.conf. - -Example: z990 crypto instruction for SHA1 algorithm is available - - add the following line to /etc/modprobe.conf (assuming the - z990 crypto modules for SHA1 is called sha1_z990): - - alias sha1 sha1_z990 - - -> when the sha1 algorithm is requested through the crypto API - (which has a module autoloader) the z990 module will be loaded. - -TBD: a userspace module probin mechanism - something like 'probe sha1 sha1_z990 sha1' in modprobe.conf - -> try module sha1_z990, if it fails to load load standard module sha1 - the 'probe' statement is currently not supported in modprobe.conf - - -4. Currently implemented z990 crypto algorithms -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The following crypto algorithms with z990 MSA support are currently implemented. -The name of each algorithm under which it is registered in crypto API and the -name of the respective module is given in square brackets. - -- SHA1 Digest Algorithm [sha1 -> sha1_z990] -- DES Encrypt/Decrypt Algorithm (64bit key) [des -> des_z990] -- Tripple DES Encrypt/Decrypt Algorithm (128bit key) [des3_ede128 -> des_z990] -- Tripple DES Encrypt/Decrypt Algorithm (192bit key) [des3_ede -> des_z990] - -In order to load, for example, the sha1_z990 module when the sha1 algorithm is -requested (see 3.2.) add 'alias sha1 sha1_z990' to /etc/modprobe.conf. - diff --git a/Documentation/s390/driver-model.txt b/Documentation/s390/driver-model.txt index 19461958e2b..ed265cf54cd 100644 --- a/Documentation/s390/driver-model.txt +++ b/Documentation/s390/driver-model.txt @@ -8,19 +8,27 @@ All devices which can be addressed by means of ccws are called 'CCW devices' - even if they aren't actually driven by ccws. All ccw devices are accessed via a subchannel, this is reflected in the -structures under root/: +structures under devices/: -root/ - - sys - - legacy +devices/ + - system/ - css0/ - 0.0.0000/0.0.0815/ - 0.0.0001/0.0.4711/ - 0.0.0002/ + - 0.1.0000/0.1.1234/ ... + - defunct/ -In this example, device 0815 is accessed via subchannel 0, device 4711 via -subchannel 1, and subchannel 2 is a non-I/O subchannel. +In this example, device 0815 is accessed via subchannel 0 in subchannel set 0, +device 4711 via subchannel 1 in subchannel set 0, and subchannel 2 is a non-I/O +subchannel. Device 1234 is accessed via subchannel 0 in subchannel set 1. + +The subchannel named 'defunct' does not represent any real subchannel on the +system; it is a pseudo subchannel where disconnected ccw devices are moved to +if they are displaced by another ccw device becoming operational on their +former subchannel. The ccw devices will be moved again to a proper subchannel +if they become operational again on that subchannel. You should address a ccw device via its bus id (e.g. 0.0.4711); the device can be found under bus/ccw/devices/. @@ -36,7 +44,7 @@ availability: Can be 'good' or 'boxed'; 'no path' or 'no device' for online: An interface to set the device online and offline. In the special case of the device being disconnected (see the - notify function under 1.2), piping 0 to online will focibly delete + notify function under 1.2), piping 0 to online will forcibly delete the device. The device drivers can add entries to export per-device data and interfaces. @@ -98,7 +106,7 @@ is not available to the device driver. Each driver should declare in a MODULE_DEVICE_TABLE into which CU types/models and/or device types/models it is interested. This information can later be found -found in the struct ccw_device_id fields: +in the struct ccw_device_id fields: struct ccw_device_id { __u16 match_flags; @@ -156,7 +164,7 @@ notify: This function is called by the common I/O layer for some state changes * In online state, device detached (CIO_GONE) or last path gone (CIO_NO_PATH). The driver must return !0 to keep the device; for return code 0, the device will be deleted as usual (also when no - notify function is registerd). If the driver wants to keep the + notify function is registered). If the driver wants to keep the device, it is moved into disconnected state. * In disconnected state, device operational again (CIO_OPER). The common I/O layer performs some sanity checks on device number and @@ -209,9 +217,14 @@ Each ccwgroup device also provides an 'ungroup' attribute to destroy the device again (only when offline). This is a generic ccwgroup mechanism (the driver does not need to implement anything beyond normal removal routines). +A ccw device which is a member of a ccwgroup device carries a pointer to the +ccwgroup device in the driver_data of its device struct. This field must not be +touched by the driver - it should use the ccwgroup device's driver_data for its +private data. + To implement a ccwgroup driver, please refer to include/asm/ccwgroup.h. Keep in -mind that most drivers will need to implement both a ccwgroup and a ccw driver -(unless you have a meta ccw driver, like cu3088 for lcs and ctc). +mind that most drivers will need to implement both a ccwgroup and a ccw +driver. 2. Channel paths @@ -222,7 +235,7 @@ and are called 'chp0.<chpid>'. They have no driver and do not belong to any bus. Please note, that unlike /proc/chpids in 2.4, the channel path objects reflect only the logical state and not the physical state, since we cannot track the latter consistently due to lacking machine support (we don't need to be aware -of anyway). +of it anyway). status - Can be 'online' or 'offline'. Piping 'on' or 'off' sets the chpid logically online/offline. @@ -231,16 +244,25 @@ status - Can be 'online' or 'offline'. a channel path the user knows to be online, but the machine hasn't created a machine check for. +type - The physical type of the channel path. + +shared - Whether the channel path is shared. + +cmg - The channel measurement group. 3. System devices ----------------- -Note: cpus may yet be added here. - 3.1 xpram --------- -xpram shows up under sys/ as 'xpram'. +xpram shows up under devices/system/ as 'xpram'. + +3.2 cpus +-------- + +For each cpu, a directory is created under devices/system/cpu/. Each cpu has an +attribute 'online' which can be 0 or 1. 4. Other devices @@ -250,7 +272,7 @@ xpram shows up under sys/ as 'xpram'. ----------- The netiucv driver creates an attribute 'connection' under -bus/iucv/drivers/netiucv. Piping to this attibute creates a new netiucv +bus/iucv/drivers/netiucv. Piping to this attribute creates a new netiucv connection to the specified host. Netiucv connections show up under devices/iucv/ as "netiucv<ifnum>". The interface diff --git a/Documentation/s390/kvm.txt b/Documentation/s390/kvm.txt new file mode 100644 index 00000000000..85f3280d7ef --- /dev/null +++ b/Documentation/s390/kvm.txt @@ -0,0 +1,125 @@ +*** BIG FAT WARNING *** +The kvm module is currently in EXPERIMENTAL state for s390. This means that +the interface to the module is not yet considered to remain stable. Thus, be +prepared that we keep breaking your userspace application and guest +compatibility over and over again until we feel happy with the result. Make sure +your guest kernel, your host kernel, and your userspace launcher are in a +consistent state. + +This Documentation describes the unique ioctl calls to /dev/kvm, the resulting +kvm-vm file descriptors, and the kvm-vcpu file descriptors that differ from x86. + +1. ioctl calls to /dev/kvm +KVM does support the following ioctls on s390 that are common with other +architectures and do behave the same: +KVM_GET_API_VERSION +KVM_CREATE_VM (*) see note +KVM_CHECK_EXTENSION +KVM_GET_VCPU_MMAP_SIZE + +Notes: +* KVM_CREATE_VM may fail on s390, if the calling process has multiple +threads and has not called KVM_S390_ENABLE_SIE before. + +In addition, on s390 the following architecture specific ioctls are supported: +ioctl: KVM_S390_ENABLE_SIE +args: none +see also: include/linux/kvm.h +This call causes the kernel to switch on PGSTE in the user page table. This +operation is needed in order to run a virtual machine, and it requires the +calling process to be single-threaded. Note that the first call to KVM_CREATE_VM +will implicitly try to switch on PGSTE if the user process has not called +KVM_S390_ENABLE_SIE before. User processes that want to launch multiple threads +before creating a virtual machine have to call KVM_S390_ENABLE_SIE, or will +observe an error calling KVM_CREATE_VM. Switching on PGSTE is a one-time +operation, is not reversible, and will persist over the entire lifetime of +the calling process. It does not have any user-visible effect other than a small +performance penalty. + +2. ioctl calls to the kvm-vm file descriptor +KVM does support the following ioctls on s390 that are common with other +architectures and do behave the same: +KVM_CREATE_VCPU +KVM_SET_USER_MEMORY_REGION (*) see note +KVM_GET_DIRTY_LOG (**) see note + +Notes: +* kvm does only allow exactly one memory slot on s390, which has to start + at guest absolute address zero and at a user address that is aligned on any + page boundary. This hardware "limitation" allows us to have a few unique + optimizations. The memory slot doesn't have to be filled + with memory actually, it may contain sparse holes. That said, with different + user memory layout this does still allow a large flexibility when + doing the guest memory setup. +** KVM_GET_DIRTY_LOG doesn't work properly yet. The user will receive an empty +log. This ioctl call is only needed for guest migration, and we intend to +implement this one in the future. + +In addition, on s390 the following architecture specific ioctls for the kvm-vm +file descriptor are supported: +ioctl: KVM_S390_INTERRUPT +args: struct kvm_s390_interrupt * +see also: include/linux/kvm.h +This ioctl is used to submit a floating interrupt for a virtual machine. +Floating interrupts may be delivered to any virtual cpu in the configuration. +Only some interrupt types defined in include/linux/kvm.h make sense when +submitted as floating interrupts. The following interrupts are not considered +to be useful as floating interrupts, and a call to inject them will result in +-EINVAL error code: program interrupts and interprocessor signals. Valid +floating interrupts are: +KVM_S390_INT_VIRTIO +KVM_S390_INT_SERVICE + +3. ioctl calls to the kvm-vcpu file descriptor +KVM does support the following ioctls on s390 that are common with other +architectures and do behave the same: +KVM_RUN +KVM_GET_REGS +KVM_SET_REGS +KVM_GET_SREGS +KVM_SET_SREGS +KVM_GET_FPU +KVM_SET_FPU + +In addition, on s390 the following architecture specific ioctls for the +kvm-vcpu file descriptor are supported: +ioctl: KVM_S390_INTERRUPT +args: struct kvm_s390_interrupt * +see also: include/linux/kvm.h +This ioctl is used to submit an interrupt for a specific virtual cpu. +Only some interrupt types defined in include/linux/kvm.h make sense when +submitted for a specific cpu. The following interrupts are not considered +to be useful, and a call to inject them will result in -EINVAL error code: +service processor calls and virtio interrupts. Valid interrupt types are: +KVM_S390_PROGRAM_INT +KVM_S390_SIGP_STOP +KVM_S390_RESTART +KVM_S390_SIGP_SET_PREFIX +KVM_S390_INT_EMERGENCY + +ioctl: KVM_S390_STORE_STATUS +args: unsigned long +see also: include/linux/kvm.h +This ioctl stores the state of the cpu at the guest real address given as +argument, unless one of the following values defined in include/linux/kvm.h +is given as argument: +KVM_S390_STORE_STATUS_NOADDR - the CPU stores its status to the save area in +absolute lowcore as defined by the principles of operation +KVM_S390_STORE_STATUS_PREFIXED - the CPU stores its status to the save area in +its prefix page just like the dump tool that comes with zipl. This is useful +to create a system dump for use with lkcdutils or crash. + +ioctl: KVM_S390_SET_INITIAL_PSW +args: struct kvm_s390_psw * +see also: include/linux/kvm.h +This ioctl can be used to set the processor status word (psw) of a stopped cpu +prior to running it with KVM_RUN. Note that this call is not required to modify +the psw during sie intercepts that fall back to userspace because struct kvm_run +does contain the psw, and this value is evaluated during reentry of KVM_RUN +after the intercept exit was recognized. + +ioctl: KVM_S390_INITIAL_RESET +args: none +see also: include/linux/kvm.h +This ioctl can be used to perform an initial cpu reset as defined by the +principles of operation. The target cpu has to be in stopped state. diff --git a/Documentation/s390/monreader.txt b/Documentation/s390/monreader.txt index d843bb04906..d3729585fdb 100644 --- a/Documentation/s390/monreader.txt +++ b/Documentation/s390/monreader.txt @@ -10,7 +10,7 @@ Author: Gerald Schaefer (geraldsc@de.ibm.com) Description =========== This item delivers a new Linux API in the form of a misc char device that is -useable from user space and allows read access to the z/VM Monitor Records +usable from user space and allows read access to the z/VM Monitor Records collected by the *MONITOR System Service of z/VM. @@ -83,7 +83,7 @@ This loads the module and sets the DCSS name to "MYDCSS". NOTE: ----- -This API provides no interface to control the *MONITOR service, e.g. specifiy +This API provides no interface to control the *MONITOR service, e.g. specify which data should be collected. This can be done by the CP command MONITOR (Class E privileged), see "CP Command and Utility Reference". diff --git a/Documentation/s390/qeth.txt b/Documentation/s390/qeth.txt new file mode 100644 index 00000000000..74122ada994 --- /dev/null +++ b/Documentation/s390/qeth.txt @@ -0,0 +1,50 @@ +IBM s390 QDIO Ethernet Driver + +HiperSockets Bridge Port Support + +Uevents + +To generate the events the device must be assigned a role of either +a primary or a secondary Bridge Port. For more information, see +"z/VM Connectivity, SC24-6174". + +When run on HiperSockets Bridge Capable Port hardware, and the state +of some configured Bridge Port device on the channel changes, a udev +event with ACTION=CHANGE is emitted on behalf of the corresponding +ccwgroup device. The event has the following attributes: + +BRIDGEPORT=statechange - indicates that the Bridge Port device changed + its state. + +ROLE={primary|secondary|none} - the role assigned to the port. + +STATE={active|standby|inactive} - the newly assumed state of the port. + +When run on HiperSockets Bridge Capable Port hardware with host address +notifications enabled, a udev event with ACTION=CHANGE is emitted. +It is emitted on behalf of the corresponding ccwgroup device when a host +or a VLAN is registered or unregistered on the network served by the device. +The event has the following attributes: + +BRIDGEDHOST={reset|register|deregister|abort} - host address + notifications are started afresh, a new host or VLAN is registered or + deregistered on the Bridge Port HiperSockets channel, or address + notifications are aborted. + +VLAN=numeric-vlan-id - VLAN ID on which the event occurred. Not included + if no VLAN is involved in the event. + +MAC=xx:xx:xx:xx:xx:xx - MAC address of the host that is being registered + or deregistered from the HiperSockets channel. Not reported if the + event reports the creation or destruction of a VLAN. + +NTOK_BUSID=x.y.zzzz - device bus ID (CSSID, SSID and device number). + +NTOK_IID=xx - device IID. + +NTOK_CHPID=xx - device CHPID. + +NTOK_CHID=xxxx - device channel ID. + +Note that the NTOK_* attributes refer to devices other than the one +connected to the system on which the OS is running. diff --git a/Documentation/s390/s390dbf.txt b/Documentation/s390/s390dbf.txt index e24fdeada97..3da163383c9 100644 --- a/Documentation/s390/s390dbf.txt +++ b/Documentation/s390/s390dbf.txt @@ -2,7 +2,7 @@ S390 Debug Feature ================== files: arch/s390/kernel/debug.c - include/asm-s390/debug.h + arch/s390/include/asm/debug.h Description: ------------ @@ -11,7 +11,7 @@ where log records can be stored efficiently in memory, where each component (e.g. device drivers) can have one separate debug log. One purpose of this is to inspect the debug logs after a production system crash in order to analyze the reason for the crash. -If the system still runs but only a subcomponent which uses dbf failes, +If the system still runs but only a subcomponent which uses dbf fails, it is possible to look at the debug logs on a live system via the Linux debugfs filesystem. The debug feature may also very useful for kernel and driver development. @@ -36,7 +36,7 @@ switches to the next debug area. This is done in order to be sure that the records which describe the origin of the exception are not overwritten when a wrap around for the current area occurs. -The debug areas itselve are also ordered in form of a ring buffer. +The debug areas themselves are also ordered in form of a ring buffer. When an exception is thrown in the last debug area, the following debug entries are then written again in the very first area. @@ -55,7 +55,7 @@ The debug logs can be inspected in a live system through entries in the debugfs-filesystem. Under the toplevel directory "s390dbf" there is a directory for each registered component, which is named like the corresponding component. The debugfs normally should be mounted to -/sys/kernel/debug therefore the debug feature can be accessed unter +/sys/kernel/debug therefore the debug feature can be accessed under /sys/kernel/debug/s390dbf. The content of the directories are files which represent different views @@ -65,7 +65,7 @@ Predefined views for hex/ascii, sprintf and raw binary data are provided. It is also possible to define other views. The content of a view can be inspected simply by reading the corresponding debugfs file. -All debug logs have an an actual debug level (range from 0 to 6). +All debug logs have an actual debug level (range from 0 to 6). The default level is 3. Event and Exception functions have a 'level' parameter. Only debug entries with a level that is lower or equal than the actual level are written to the log. This means, when @@ -83,15 +83,15 @@ Example: It is also possible to deactivate the debug feature globally for every debug log. You can change the behavior using 2 sysctl parameters in /proc/sys/s390dbf: -There are currently 2 possible triggers, which stop the debug feature -globally. The first possbility is to use the "debug_active" sysctl. If +There are currently 2 possible triggers, which stop the debug feature +globally. The first possibility is to use the "debug_active" sysctl. If set to 1 the debug feature is running. If "debug_active" is set to 0 the debug feature is turned off. -The second trigger which stops the debug feature is an kernel oops. +The second trigger which stops the debug feature is a kernel oops. That prevents the debug feature from overwriting debug information that happened before the oops. After an oops you can reactivate the debug feature by piping 1 to /proc/sys/s390dbf/debug_active. Nevertheless, its not -suggested to use an oopsed kernel in an production environment. +suggested to use an oopsed kernel in a production environment. If you want to disallow the deactivation of the debug feature, you can use the "debug_stoppable" sysctl. If you set "debug_stoppable" to 0 the debug feature cannot be stopped. If the debug feature is already stopped, it @@ -115,6 +115,27 @@ Return Value: Handle for generated debug area Description: Allocates memory for a debug log Must not be called within an interrupt handler +---------------------------------------------------------------------------- +debug_info_t *debug_register_mode(char *name, int pages, int nr_areas, + int buf_size, mode_t mode, uid_t uid, + gid_t gid); + +Parameter: name: Name of debug log (e.g. used for debugfs entry) + pages: Number of pages, which will be allocated per area + nr_areas: Number of debug areas + buf_size: Size of data area in each debug entry + mode: File mode for debugfs files. E.g. S_IRWXUGO + uid: User ID for debugfs files. Currently only 0 is + supported. + gid: Group ID for debugfs files. Currently only 0 is + supported. + +Return Value: Handle for generated debug area + NULL if register failed + +Description: Allocates memory for a debug log + Must not be called within an interrupt handler + --------------------------------------------------------------------------- void debug_unregister (debug_info_t * id); @@ -122,7 +143,8 @@ Parameter: id: handle for debug log Return Value: none -Description: frees memory for a debug log +Description: frees memory for a debug log and removes all registered debug + views. Must not be called within an interrupt handler --------------------------------------------------------------------------- @@ -136,6 +158,16 @@ Return Value: none Description: Sets new actual debug level if new_level is valid. --------------------------------------------------------------------------- +bool debug_level_enabled (debug_info_t * id, int level); + +Parameter: id: handle for debug log + level: debug level + +Return Value: True if level is less or equal to the current debug level. + +Description: Returns true if debug events for the specified level would be + logged. Otherwise returns false. +--------------------------------------------------------------------------- void debug_stop_all(void); Parameter: none @@ -468,12 +500,19 @@ The hex_ascii view shows the data field in hex and ascii representation The raw view returns a bytestream as the debug areas are stored in memory. The sprintf view formats the debug entries in the same way as the sprintf -function would do. The sprintf event/expection fuctions write to the +function would do. The sprintf event/exception functions write to the debug entry a pointer to the format string (size = sizeof(long)) and for each vararg a long value. So e.g. for a debug entry with a format string plus two varargs one would need to allocate a (3 * sizeof(long)) byte data area in the debug_register() function. +IMPORTANT: Using "%s" in sprintf event functions is dangerous. You can only +use "%s" in the sprintf event functions, if the memory for the passed string is +available as long as the debug feature exists. The reason behind this is that +due to performance considerations only a pointer to the string is stored in +the debug feature. If you log a string that is freed afterwards, you will get +an OOPS when inspecting the debug feature, because then the debug feature will +access the already freed memory. NOTE: If using the sprintf view do NOT use other event/exception functions than the sprintf-event and -exception functions. @@ -556,7 +595,7 @@ The input_proc can be used to implement functionality when it is written to the view (e.g. like with 'echo "0" > /sys/kernel/debug/s390dbf/dasd/level). For header_proc there can be used the default function -debug_dflt_header_fn() which is defined in in debug.h. +debug_dflt_header_fn() which is defined in debug.h. and which produces the same header output as the predefined views. E.g: 00 00964419409:440761 2 - 00 88023ec diff --git a/Documentation/s390/zfcpdump.txt b/Documentation/s390/zfcpdump.txt new file mode 100644 index 00000000000..dc929be9601 --- /dev/null +++ b/Documentation/s390/zfcpdump.txt @@ -0,0 +1,52 @@ +The s390 SCSI dump tool (zfcpdump) + +System z machines (z900 or higher) provide hardware support for creating system +dumps on SCSI disks. The dump process is initiated by booting a dump tool, which +has to create a dump of the current (probably crashed) Linux image. In order to +not overwrite memory of the crashed Linux with data of the dump tool, the +hardware saves some memory plus the register sets of the boot CPU before the +dump tool is loaded. There exists an SCLP hardware interface to obtain the saved +memory afterwards. Currently 32 MB are saved. + +This zfcpdump implementation consists of a Linux dump kernel together with +a user space dump tool, which are loaded together into the saved memory region +below 32 MB. zfcpdump is installed on a SCSI disk using zipl (as contained in +the s390-tools package) to make the device bootable. The operator of a Linux +system can then trigger a SCSI dump by booting the SCSI disk, where zfcpdump +resides on. + +The kernel part of zfcpdump is implemented as a debugfs file under "zcore/mem", +which exports memory and registers of the crashed Linux in an s390 +standalone dump format. It can be used in the same way as e.g. /dev/mem. The +dump format defines a 4K header followed by plain uncompressed memory. The +register sets are stored in the prefix pages of the respective CPUs. To build a +dump enabled kernel with the zcore driver, the kernel config option +CONFIG_CRASH_DUMP has to be set. When reading from "zcore/mem", the part of +memory, which has been saved by hardware is read by the driver via the SCLP +hardware interface. The second part is just copied from the non overwritten real +memory. + +Since kernel version 3.12 also the /proc/vmcore file can also be used to access +the dump. + +To get a valid zfcpdump kernel configuration use "make zfcpdump_defconfig". + +The s390 zipl tool looks for the zfcpdump kernel and optional initrd/initramfs +under the following locations: + +* kernel: <zfcpdump directory>/zfcpdump.image +* ramdisk: <zfcpdump directory>/zfcpdump.rd + +The zfcpdump directory is defined in the s390-tools package. + +The user space application of zfcpdump can reside in an intitramfs or an +initrd. It can also be included in a built-in kernel initramfs. The application +reads from /proc/vmcore or zcore/mem and writes the system dump to a SCSI disk. + +The s390-tools package version 1.24.0 and above builds an external zfcpdump +initramfs with a user space application that writes the dump to a SCSI +partition. + +For more information on how to use zfcpdump refer to the s390 'Using the Dump +Tools book', which is available from +http://www.ibm.com/developerworks/linux/linux390. |