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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-05 14:27:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-05 14:27:02 -0700
commit3526dd0c7832f1011a0477cc6d903662bae05ea8 (patch)
tree22fbac64eb40a0b29bfa4c029695f39b2f591e62 /Documentation
parentdd972f924df6bdbc0ab185a38d5d2361dbc26311 (diff)
parentbc6d65e6dc89c3b7ff78e4ad797117c122ffde8e (diff)
downloadlwn-3526dd0c7832f1011a0477cc6d903662bae05ea8.tar.gz
lwn-3526dd0c7832f1011a0477cc6d903662bae05ea8.zip
Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe: "It's a pretty quiet round this time, which is nice. This contains: - series from Bart, cleaning up the way we set/test/clear atomic queue flags. - series from Bart, fixing races between gendisk and queue registration and removal. - set of bcache fixes and improvements from various folks, by way of Michael Lyle. - set of lightnvm updates from Matias, most of it being the 1.2 to 2.0 transition. - removal of unused DIO flags from Nikolay. - blk-mq/sbitmap memory ordering fixes from Omar. - divide-by-zero fix for BFQ from Paolo. - minor documentation patches from Randy. - timeout fix from Tejun. - Alpha "can't write a char atomically" fix from Mikulas. - set of NVMe fixes by way of Keith. - bsg and bsg-lib improvements from Christoph. - a few sed-opal fixes from Jonas. - cdrom check-disk-change deadlock fix from Maurizio. - various little fixes, comment fixes, etc from various folks" * tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits) blk-mq: Directly schedule q->timeout_work when aborting a request blktrace: fix comment in blktrace_api.h lightnvm: remove function name in strings lightnvm: pblk: remove some unnecessary NULL checks lightnvm: pblk: don't recover unwritten lines lightnvm: pblk: implement 2.0 support lightnvm: pblk: implement get log report chunk lightnvm: pblk: rename ppaf* to addrf* lightnvm: pblk: check for supported version lightnvm: implement get log report chunk helpers lightnvm: make address conversions depend on generic device lightnvm: add support for 2.0 address format lightnvm: normalize geometry nomenclature lightnvm: complete geo structure with maxoc* lightnvm: add shorten OCSSD version in geo lightnvm: add minor version to generic geometry lightnvm: simplify geometry structure lightnvm: pblk: refactor init/exit sequences lightnvm: Avoid validation of default op value lightnvm: centralize permission check for lightnvm ioctl ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/cdrom/cdrom-standard.tex31
-rw-r--r--Documentation/fault-injection/fault-injection.txt8
-rw-r--r--Documentation/fault-injection/nvme-fault-injection.txt116
3 files changed, 145 insertions, 10 deletions
diff --git a/Documentation/cdrom/cdrom-standard.tex b/Documentation/cdrom/cdrom-standard.tex
index 8f85b0e41046..f7cd455973f7 100644
--- a/Documentation/cdrom/cdrom-standard.tex
+++ b/Documentation/cdrom/cdrom-standard.tex
@@ -234,6 +234,7 @@ struct& cdrom_device_ops\ \{ \hidewidth\cr
&int& (* open)(struct\ cdrom_device_info *, int)\cr
&void& (* release)(struct\ cdrom_device_info *);\cr
&int& (* drive_status)(struct\ cdrom_device_info *, int);\cr
+ &unsigned\ int& (* check_events)(struct\ cdrom_device_info *, unsigned\ int, int);\cr
&int& (* media_changed)(struct\ cdrom_device_info *, int);\cr
&int& (* tray_move)(struct\ cdrom_device_info *, int);\cr
&int& (* lock_door)(struct\ cdrom_device_info *, int);\cr
@@ -245,10 +246,9 @@ struct& cdrom_device_ops\ \{ \hidewidth\cr
&int& (* reset)(struct\ cdrom_device_info *);\cr
&int& (* audio_ioctl)(struct\ cdrom_device_info *, unsigned\ int,
void *{});\cr
- &int& (* dev_ioctl)(struct\ cdrom_device_info *, unsigned\ int,
- unsigned\ long);\cr
\noalign{\medskip}
&const\ int& capability;& capability flags \cr
+ &int& (* generic_packet)(struct\ cdrom_device_info *, struct\ packet_command *{});\cr
\};\cr
}
$$
@@ -274,19 +274,32 @@ $$
\halign{$#$\ \hfil&$#$\ \hfil&\hbox to 10em{$#$\hss}&
$/*$ \rm# $*/$\hfil\cr
struct& cdrom_device_info\ \{ \hidewidth\cr
- & struct\ cdrom_device_ops *& ops;& device operations for this major\cr
- & struct\ cdrom_device_info *& next;& next device_info for this major\cr
+ & const\ struct\ cdrom_device_ops *& ops;& device operations for this major\cr
+ & struct\ list_head& list;& linked list of all device_info\cr
+ & struct\ gendisk *& disk;& matching block layer disk\cr
& void *& handle;& driver-dependent data\cr
\noalign{\medskip}
- & kdev_t& dev;& device number (incorporates minor)\cr
& int& mask;& mask of capability: disables them \cr
& int& speed;& maximum speed for reading data \cr
& int& capacity;& number of discs in a jukebox \cr
\noalign{\medskip}
- &int& options : 30;& options flags \cr
+ &unsigned\ int& options : 30;& options flags \cr
&unsigned& mc_flags : 2;& media-change buffer flags \cr
+ &unsigned\ int& vfs_events;& cached events for vfs path\cr
+ &unsigned\ int& ioctl_events;& cached events for ioctl path\cr
& int& use_count;& number of times device is opened\cr
& char& name[20];& name of the device type\cr
+\noalign{\medskip}
+ &__u8& sanyo_slot : 2;& Sanyo 3-CD changer support\cr
+ &__u8& keeplocked : 1;& CDROM_LOCKDOOR status\cr
+ &__u8& reserved : 5;& not used yet\cr
+ & int& cdda_method;& see CDDA_* flags\cr
+ &__u8& last_sense;& saves last sense key\cr
+ &__u8& media_written;& dirty flag, DVD+RW bookkeeping\cr
+ &unsigned\ short& mmc3_profile;& current MMC3 profile\cr
+ & int& for_data;& unknown:TBD\cr
+ & int\ (* exit)\ (struct\ cdrom_device_info *);&& unknown:TBD\cr
+ & int& mrw_mode_page;& which MRW mode page is in use\cr
\}\cr
}$$
Using this $struct$, a linked list of the registered minor devices is
@@ -298,9 +311,7 @@ The $mask$ flags can be used to mask out some of the capabilities listed
in $ops\to capability$, if a specific drive doesn't support a feature
of the driver. The value $speed$ specifies the maximum head-rate of the
drive, measured in units of normal audio speed (176\,kB/sec raw data or
-150\,kB/sec file system data). The value $n_discs$ should reflect the
-number of discs the drive can hold simultaneously, if it is designed
-as a juke-box, or otherwise~1. The parameters are declared $const$
+150\,kB/sec file system data). The parameters are declared $const$
because they describe properties of the drive, which don't change after
registration.
@@ -1002,7 +1013,7 @@ taken over the torch in maintaining \cdromc\ and integrating much
\cdrom-related code in the 2.1-kernel. Thanks to Scott Snyder and
Gerd Knorr, who were the first to implement this interface for SCSI
and IDE-CD drivers and added many ideas for extension of the data
-structures relative to kernel~2.0. Further thanks to Heiko Ei{\sz}feldt,
+structures relative to kernel~2.0. Further thanks to Heiko Ei{\ss}feldt,
Thomas Quinot, Jon Tombs, Ken Pizzini, Eberhard M\"onkeberg and Andrew
Kroll, the \linux\ \cdrom\ device driver developers who were kind
enough to give suggestions and criticisms during the writing. Finally
diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt
index de1dc35fe500..4d1b7b4ccfaf 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.txt
@@ -36,6 +36,14 @@ o fail_function
ALLOW_ERROR_INJECTION() macro, by setting debugfs entries
under /sys/kernel/debug/fail_function. No boot option supported.
+o NVMe fault injection
+
+ inject NVMe status code and retry flag on devices permitted by setting
+ debugfs entries under /sys/kernel/debug/nvme*/fault_inject. The default
+ status code is NVME_SC_INVALID_OPCODE with no retry. The status code and
+ retry flag can be set via the debugfs.
+
+
Configure fault-injection capabilities behavior
-----------------------------------------------
diff --git a/Documentation/fault-injection/nvme-fault-injection.txt b/Documentation/fault-injection/nvme-fault-injection.txt
new file mode 100644
index 000000000000..8fbf3bf60b62
--- /dev/null
+++ b/Documentation/fault-injection/nvme-fault-injection.txt
@@ -0,0 +1,116 @@
+NVMe Fault Injection
+====================
+Linux's fault injection framework provides a systematic way to support
+error injection via debugfs in the /sys/kernel/debug directory. When
+enabled, the default NVME_SC_INVALID_OPCODE with no retry will be
+injected into the nvme_end_request. Users can change the default status
+code and no retry flag via the debugfs. The list of Generic Command
+Status can be found in include/linux/nvme.h
+
+Following examples show how to inject an error into the nvme.
+
+First, enable CONFIG_FAULT_INJECTION_DEBUG_FS kernel config,
+recompile the kernel. After booting up the kernel, do the
+following.
+
+Example 1: Inject default status code with no retry
+---------------------------------------------------
+
+mount /dev/nvme0n1 /mnt
+echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times
+echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability
+cp a.file /mnt
+
+Expected Result:
+
+cp: cannot stat ‘/mnt/a.file’: Input/output error
+
+Message from dmesg:
+
+FAULT_INJECTION: forcing a failure.
+name fault_inject, interval 1, probability 100, space 0, times 1
+CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc8+ #2
+Hardware name: innotek GmbH VirtualBox/VirtualBox,
+BIOS VirtualBox 12/01/2006
+Call Trace:
+ <IRQ>
+ dump_stack+0x5c/0x7d
+ should_fail+0x148/0x170
+ nvme_should_fail+0x2f/0x50 [nvme_core]
+ nvme_process_cq+0xe7/0x1d0 [nvme]
+ nvme_irq+0x1e/0x40 [nvme]
+ __handle_irq_event_percpu+0x3a/0x190
+ handle_irq_event_percpu+0x30/0x70
+ handle_irq_event+0x36/0x60
+ handle_fasteoi_irq+0x78/0x120
+ handle_irq+0xa7/0x130
+ ? tick_irq_enter+0xa8/0xc0
+ do_IRQ+0x43/0xc0
+ common_interrupt+0xa2/0xa2
+ </IRQ>
+RIP: 0010:native_safe_halt+0x2/0x10
+RSP: 0018:ffffffff82003e90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
+RAX: ffffffff817a10c0 RBX: ffffffff82012480 RCX: 0000000000000000
+RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
+RBP: 0000000000000000 R08: 000000008e38ce64 R09: 0000000000000000
+R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82012480
+R13: ffffffff82012480 R14: 0000000000000000 R15: 0000000000000000
+ ? __sched_text_end+0x4/0x4
+ default_idle+0x18/0xf0
+ do_idle+0x150/0x1d0
+ cpu_startup_entry+0x6f/0x80
+ start_kernel+0x4c4/0x4e4
+ ? set_init_arg+0x55/0x55
+ secondary_startup_64+0xa5/0xb0
+ print_req_error: I/O error, dev nvme0n1, sector 9240
+EXT4-fs error (device nvme0n1): ext4_find_entry:1436:
+inode #2: comm cp: reading directory lblock 0
+
+Example 2: Inject default status code with retry
+------------------------------------------------
+
+mount /dev/nvme0n1 /mnt
+echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times
+echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability
+echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/status
+echo 0 > /sys/kernel/debug/nvme0n1/fault_inject/dont_retry
+
+cp a.file /mnt
+
+Expected Result:
+
+command success without error
+
+Message from dmesg:
+
+FAULT_INJECTION: forcing a failure.
+name fault_inject, interval 1, probability 100, space 0, times 1
+CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.15.0-rc8+ #4
+Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
+Call Trace:
+ <IRQ>
+ dump_stack+0x5c/0x7d
+ should_fail+0x148/0x170
+ nvme_should_fail+0x30/0x60 [nvme_core]
+ nvme_loop_queue_response+0x84/0x110 [nvme_loop]
+ nvmet_req_complete+0x11/0x40 [nvmet]
+ nvmet_bio_done+0x28/0x40 [nvmet]
+ blk_update_request+0xb0/0x310
+ blk_mq_end_request+0x18/0x60
+ flush_smp_call_function_queue+0x3d/0xf0
+ smp_call_function_single_interrupt+0x2c/0xc0
+ call_function_single_interrupt+0xa2/0xb0
+ </IRQ>
+RIP: 0010:native_safe_halt+0x2/0x10
+RSP: 0018:ffffc9000068bec0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff04
+RAX: ffffffff817a10c0 RBX: ffff88011a3c9680 RCX: 0000000000000000
+RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
+RBP: 0000000000000001 R08: 000000008e38c131 R09: 0000000000000000
+R10: 0000000000000000 R11: 0000000000000000 R12: ffff88011a3c9680
+R13: ffff88011a3c9680 R14: 0000000000000000 R15: 0000000000000000
+ ? __sched_text_end+0x4/0x4
+ default_idle+0x18/0xf0
+ do_idle+0x150/0x1d0
+ cpu_startup_entry+0x6f/0x80
+ start_secondary+0x187/0x1e0
+ secondary_startup_64+0xa5/0xb0