Ilya Dryomov 9b60e70b3b rbd: add support for single-major device number allocation scheme ... Currently each rbd device is allocated its own major number, which leads to a hard limit of 230-250 images mapped at once. This commit adds support for a new single-major device number allocation scheme, which is hidden behind a new single_major boolean module parameter and is disabled by default for backwards compatibility reasons. (Old userspace cannot correctly unmap images mapped under single-major scheme and would essentially just unmap a random image, if that.) $ rbd showmapped id pool image snap device 0 rbd b100 - /dev/rbd0 1 rbd b101 - /dev/rbd1 2 rbd b102 - /dev/rbd2 3 rbd b103 - /dev/rbd3 Old scheme (modprobe rbd): $ ls -l /dev/rbd* brw-rw---- 1 root disk 253, 0 Dec 10 12:24 /dev/rbd0 brw-rw---- 1 root disk 252, 0 Dec 10 12:28 /dev/rbd1 brw-rw---- 1 root disk 252, 1 Dec 10 12:28 /dev/rbd1p1 brw-rw---- 1 root disk 252, 2 Dec 10 12:28 /dev/rbd1p2 brw-rw---- 1 root disk 252, 3 Dec 10 12:28 /dev/rbd1p3 brw-rw---- 1 root disk 251, 0 Dec 10 12:28 /dev/rbd2 brw-rw---- 1 root disk 251, 1 Dec 10 12:28 /dev/rbd2p1 brw-rw---- 1 root disk 250, 0 Dec 10 12:24 /dev/rbd3 New scheme (modprobe rbd single_major=Y): $ ls -l /dev/rbd* brw-rw---- 1 root disk 253, 0 Dec 10 12:30 /dev/rbd0 brw-rw---- 1 root disk 253, 256 Dec 10 12:30 /dev/rbd1 brw-rw---- 1 root disk 253, 257 Dec 10 12:30 /dev/rbd1p1 brw-rw---- 1 root disk 253, 258 Dec 10 12:30 /dev/rbd1p2 brw-rw---- 1 root disk 253, 259 Dec 10 12:30 /dev/rbd1p3 brw-rw---- 1 root disk 253, 512 Dec 10 12:30 /dev/rbd2 brw-rw---- 1 root disk 253, 513 Dec 10 12:30 /dev/rbd2p1 brw-rw---- 1 root disk 253, 768 Dec 10 12:30 /dev/rbd3 (major 253 was assigned dynamically at module load time) The new limit is 4096 images mapped at once, and it comes from the fact that, as before, 256 minor numbers are reserved for each mapping. (A follow-up commit changes the number of minors reserved and the way we deal with partitions over that number.) If single_major is set to true, two new sysfs interfaces show up: /sys/bus/rbd/{add,remove}_single_major. These are to be used instead of /sys/bus/rbd/{add,remove}, which are disabled for backwards compatibility reasons outlined above. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>		2013-12-31 20:31:59 +02:00
..
ABI	rbd: add support for single-major device number allocation scheme	2013-12-31 20:31:59 +02:00
accounting
acpi	gpiolib / ACPI: document the GPIO descriptor based interface	2013-10-19 23:32:50 +02:00
aoe	aoe: remove do-nothing NAME="%k" term from example udev rules	2013-09-11 15:59:28 -07:00
arm	Allwinner sunXi SoCs machine additions for 3.13	2013-10-28 10:19:38 -07:00
arm64	arm64: Use 42-bit address space with 64K pages	2013-11-05 17:23:52 +00:00
auxdisplay
backlight	backlight: lp855x_bl: support new LP8555 device	2013-11-13 12:09:14 +09:00
blackfin
block	block: change config option name for cmdline partition parsing	2013-09-30 14:31:02 -07:00
blockdev	floppy: Correct documentation of driver options when used as a module.	2013-11-08 09:10:31 -07:00
bus-devices
cdrom
cgroups	memcg: support hierarchical memory.numa_stats	2013-11-13 12:09:06 +09:00
connector	connector - documentation: simplify netlink message length assignment	2013-10-02 16:03:51 -04:00
console
cpu-freq	cpufreq: Implement light weight ->target_index() routine	2013-10-25 22:42:24 +02:00
cpuidle	cpuidle: remove cpuidle_unregister_governor()	2013-10-30 01:21:24 +01:00
cris
crypto
development-process
device-mapper	dm cache: resolve small nits and improve Documentation	2013-11-12 13:11:09 -05:00
devicetree	- Various DT binding documentation updates.	2013-12-06 08:27:47 -08:00
DocBook	doc: fix generation of device-drivers	2013-11-27 20:40:04 -08:00
driver-model	spi: Updates for v3.13	2013-11-12 15:01:39 +09:00
dvb
early-userspace	Documentation: remove reference to 2.7 kernel in early-userspace	2013-08-20 12:47:28 +02:00
EDID
extcon	extcon: Simplify extcon_dev_register() prototype by removing unnecessary parameter	2013-09-27 09:37:01 +09:00
fault-injection
fb	Documentation/fb/viafb.modes fix a typo	2013-08-20 12:41:11 +02:00
filesystems	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs	2013-11-22 08:38:55 -08:00
firmware_class
fmc	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
frv
gpio	Documentation: gpiolib: add 00-INDEX file	2013-12-03 13:10:48 +01:00
hid
hwmon	Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging	2013-11-15 16:35:10 -08:00
i2c	i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH	2013-11-14 18:38:04 +01:00
i2o
ia64
ide
infiniband
input	Input: clarify gamepad API ABS values	2013-10-15 23:42:07 -07:00
ioctl	ALSA: add DICE driver	2013-10-17 21:18:32 +02:00
isdn
ja_JP
kbuild	Documentation/kbuild/kconfig.txt: 'make listnewconfig' replaces: yes "" | make oldconfig	2013-10-08 23:51:50 +02:00
kdump
ko_KR	Correct unfaithful translation on HOWTO in ko_KR	2013-08-12 17:43:13 -07:00
laptops	thinkpad-acpi: Add mute and mic-mute LED functionality	2013-10-17 14:38:44 +02:00
leds	Documentation: leds-lp5521,lp5523: update device attribute information	2013-08-26 17:22:13 -07:00
m68k
make
memory-devices
metag
mic	misc: mic: Enable OSPM suspend and resume support.	2013-10-05 18:01:42 -07:00
mips
misc-devices
mmc
mn10300
mtd	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
namespaces
netlabel
networking	tcp: tsq: restore minimal amount of queueing	2013-11-14 16:25:14 -05:00
nfc
parisc
PCI	PCI: Update pci_find_slot() description in pci.txt	2013-09-25 15:43:33 -06:00
pcmcia
power	More ACPI and power management updates for 3.13-rc1	2013-11-20 13:25:04 -08:00
powerpc	powerpc: Update the 00-Index in Documentation/powerpc	2013-08-27 14:44:27 +10:00
pps	USB: serial: invoke dcd_change ldisc's handler.	2013-09-26 09:45:40 -07:00
prctl
pti
ptp	ptp: add the PTP_SYS_OFFSET ioctl to the testptp program	2013-09-23 16:46:17 -04:00
rapidio
RCU	rcu: Fix occurrence of "the the" in checklist.txt	2013-09-25 10:07:02 -07:00
s390	s390/s390dbf: add debug_level_enabled() function	2013-10-24 17:16:53 +02:00
scheduler	H8/300 has been dead for several years, the kernel for it has	2013-11-12 14:13:14 +09:00
scsi	SCSI misc on 20130915	2013-09-15 17:41:30 -04:00
security	ima: new templates management mechanism	2013-10-25 17:17:04 -04:00
serial	serial: core: delete .set_wake() callback	2013-10-16 13:16:19 -07:00
sh
sound	ALSA: Fix typo in documentation/alsa	2013-10-29 11:38:04 +01:00
spi	spi/documentation: Fix usage of __initdata	2013-08-20 12:52:28 +02:00
sysctl	vsprintf: check real user/group id for %pK	2013-11-13 12:09:14 +09:00
target	target: Remove TF_CIT_TMPL macro	2013-10-16 13:35:02 -07:00
thermal	thermal: thermal_core: allow binding with limits on bind_params	2013-09-03 09:10:24 -04:00
timers	doc: add missing files to timers/00-INDEX	2013-10-27 21:55:50 +00:00
tpm	drivers/tpm: add xen tpmfront interface	2013-08-09 10:57:06 -04:00
trace	Documentation/trace/tracepoints.txt: add links to TRACE_EVENT documentation	2013-11-13 12:09:32 +09:00
usb	doc: usb: Fix typo in Documentation/usb/gadget_configs.txt	2013-10-31 13:31:39 +01:00
vDSO
video4linux	[media] V4L: Add support for integer menu controls with standard menu items	2013-08-18 07:12:59 -03:00
virtual	Merge branch 'kvm-ppc-queue' of git://github.com/agraf/linux-2.6 into queue	2013-11-04 10:20:57 +02:00
vm	x86, mm: do not leak page->ptl for pmd page tables	2013-11-21 16:42:28 -08:00
w1
watchdog
wimax
x86	Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-11-12 10:48:30 +09:00
xtensa
zh_CN	Documentation/zh_CN/SubmittingPatches fix a typo	2013-08-20 12:41:25 +02:00
.gitignore
00-INDEX	doc: fix a typo in Documentation/00-INDEX	2013-08-27 10:53:07 +02:00
applying-patches.txt
assoc_array.txt	Add a generic associative array implementation.	2013-09-24 10:35:17 +01:00
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt	Documentation: fix typo and update version in cachetlb.txt	2013-08-20 12:46:52 +02:00
Changes	remove obsolete references to powertweak	2013-11-27 20:34:32 -08:00
circular-buffers.txt
clk.txt	clk: add support for clock reparent on set_rate	2013-08-19 12:27:17 -07:00
coccinelle.txt
CodingStyle
cpu-hotplug.txt	MAINTAINERS: update Zwane Mwaikambo's e-mail address	2013-11-13 12:09:14 +09:00
cpu-load.txt
cputopology.txt	doc: Documentation/cputopology.txt fix typo	2013-09-04 12:59:47 +02:00
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt	cuse: add fix minor number to /dev/cuse	2013-10-01 16:44:54 +02:00
digsig.txt
DMA-API-HOWTO.txt	DMA-API: provide a helper to set both DMA and coherent DMA masks	2013-09-17 15:32:37 +01:00
DMA-API.txt	DMA-API: provide a helper to set both DMA and coherent DMA masks	2013-09-17 15:32:37 +01:00
DMA-attributes.txt	doc: Documentation/DMA-attributes.txt fix typo	2013-10-14 15:50:53 +02:00
dma-buf-sharing.txt	dma-buf: Expose buffer size to userspace (v2)	2013-09-10 11:36:45 +05:30
DMA-ISA-LPC.txt
dmaengine.txt
dmatest.txt	dmatest: add a 'wait' parameter	2013-11-14 11:04:40 -08:00
dontdiff
dynamic-debug-howto.txt
edac.txt
efi-stub.txt	EFI stub documentation updates	2013-09-25 12:34:32 +01:00
eisa.txt
email-clients.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt	gcov: compile specific gcov implementation based on gcc version	2013-11-13 12:09:34 +09:00
highuid.txt
HOWTO
hw_random.txt
hwspinlock.txt	doc: documentation/hwspinlock.txt fix typo	2013-08-27 10:46:02 +02:00
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt	doc: fix a typo about irq affinity	2013-08-20 12:59:18 +02:00
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2013-11-21 19:46:00 -08:00
kernel-per-CPU-kthreads.txt	kthread: Add pointer to vmstat-avoidance patch	2013-09-25 06:49:46 -07:00
kmemcheck.txt	Documentation/kmemcheck: update kmemcheck documentation	2013-08-27 10:47:05 +02:00
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt	lockstat: Report avg wait and hold times	2013-10-09 08:19:08 +02:00
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt	doc: Fix memory-barrier control-dependency example	2013-08-19 21:39:42 -07:00
memory-hotplug.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
mono.txt
mutex-design.txt	locking/doc: Update references to kernel/mutex.c	2013-11-11 12:41:33 +01:00
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt	drivers: phy: add generic PHY framework	2013-09-27 17:35:41 -07:00
pi-futex.txt
pinctrl.txt	pinctrl: add documentation for pinctrl_get_group_pins()	2013-10-16 15:35:21 +02:00
pnp.txt
preempt-locking.txt
printk-formats.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
pwm.txt	Documentation/pwm: Fix trivial typos	2013-10-24 10:51:33 +02:00
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches	Documentation/SubmittingPatches: Request summaries for commit references	2013-08-20 12:58:15 +02:00
svga.txt
sysfs-rules.txt
sysrq.txt	sysrq: Allow magic SysRq key functions to be disabled through Kconfig	2013-10-16 13:01:44 -07:00
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt	vfio: fix documentation	2013-09-05 16:36:21 -06:00
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt	workqueue: Correct/Drop references to gcwq in Documentation	2013-08-21 10:32:09 -04:00
ww-mutex-design.txt
xz.txt
zorro.txt