linux/drivers
Lars-Peter Clausen 9e69c935fa iio: Add reference counting for buffers
Since the buffer is accessed by userspace we can not just free the buffers
memory once we are done with it in kernel space. There might still be open file
descriptors and userspace still might be accessing the buffer. This patch adds
support for reference counting to the IIO buffers. When a buffer is created and
initialized its initial reference count is set to 1. Instead of freeing the
memory of the buffer the buffer's _free() function will drop that reference
again. But only after the last reference to the buffer has been dropped the
buffer the buffer's memory will be freed. The IIO device will take a reference
to its primary buffer. The patch adds a small helper function for this called
iio_device_attach_buffer() which will get a reference to the buffer and assign
the buffer to the IIO device. This function must be used instead of assigning
the buffer to the device by hand. The reference is only dropped once the IIO
device is freed and we can be sure that there are no more open file handles. A
reference to a buffer will also be taken whenever the buffer is active to avoid
the buffer being freed while data is still being send to it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-10-12 12:04:01 +01:00
..
accessibility
acpi ACPI: Use EXPORT_SYMBOL() for acpi_bus_get_device() 2013-10-01 23:02:43 +02:00
amba
ata update contact information for Mikael Pettersson 2013-09-25 13:27:42 -07:00
atm atm: nicstar: fix regression made by previous patch 2013-09-15 22:18:55 -04:00
auxdisplay
base driver core : Fix use after free of dev->parent in device_shutdown 2013-09-26 14:46:11 -07:00
bcma bcma: make bcma_core_pci_{up,down}() callable from atomic context 2013-09-26 14:02:33 -04:00
block cciss: fix info leak in cciss_ioctl32_passthru() 2013-09-24 17:00:26 -07:00
bluetooth Bluetooth: btusb: Add support for Belkin F8065bf 2013-09-23 17:44:25 -03:00
bus bus: mvebu-mbus: Fix optional pcie-mem/io-aperture properties 2013-10-01 17:04:17 +00:00
cdrom
char Bug-fixes: 2013-09-25 15:50:53 -07:00
clk The common clk framework changes for 3.12 are dominated by clock driver 2013-09-09 15:49:04 -07:00
clocksource clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast 2013-09-26 02:31:04 +02:00
connector
cpufreq intel_pstate: fix no_turbo 2013-10-01 22:51:11 +02:00
cpuidle ACPI and power management fixes for 3.12-rc1 2013-09-12 11:22:45 -07:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux 2013-09-07 12:53:35 +10:00
dca
devfreq
dio
dma dmaengine: imx-dma: fix callback path in tasklet 2013-10-04 14:35:03 +05:30
edac Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2013-09-06 11:14:33 -07:00
eisa
extcon Driver core patches for 3.12-rc1 2013-09-03 11:37:15 -07:00
firewire firewire: ohci: Fix deadlock at bus reset 2013-08-29 22:35:05 +02:00
firmware firmware/dmi_scan: drop OOM messages 2013-09-11 15:58:51 -07:00
fmc
gpio Fixes for the GPIO tree for v3.12: 2013-10-05 12:11:40 -07:00
gpu Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-09-29 10:02:40 -07:00
hid HID: Delay opening HID device 2013-10-01 16:19:08 +01:00
hsi
hv Drivers: hv: vmbus: Terminate vmbus version negotiation on timeout 2013-09-26 14:20:22 -07:00
hwmon hwmon: (applesmc) Check key count before proceeding 2013-09-26 03:48:43 -07:00
hwspinlock
i2c i2c: ismt: initialize DMA buffer 2013-09-28 16:32:12 +02:00
ide ide: sgiioc4: Staticize ioc4_ide_attach_one() 2013-09-05 15:21:30 -04:00
idle
iio iio: Add reference counting for buffers 2013-10-12 12:04:01 +01:00
infiniband ib_srpt: always set response for task management 2013-10-03 04:23:17 -07:00
input First round of new drivers, functionality and cleanups for IIO in the 3.13 cycle 2013-09-22 11:30:12 -07:00
iommu iommu/arm-smmu: don't enable SMMU device until probing has completed 2013-09-17 12:03:11 +01:00
ipack
irqchip ARM: SoC late changes for v3.12 2013-09-09 16:35:29 -07:00
isdn isdn: hfcpci_softirq: get func return to suppress compiler warning 2013-09-15 22:27:04 -04:00
leds Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2013-09-12 11:35:33 -07:00
lguest lguest: fix guest kernel stack overflow when TF bit set. 2013-09-06 08:09:27 +09:30
macintosh
mailbox mailbox: remove unnecessary platform_set_drvdata() 2013-09-18 12:02:00 -07:00
md A set of device-mapper fixes for 3.12. 2013-09-25 15:12:46 -07:00
media Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
memory ARM: SoC platform changes for 3.12 2013-09-06 13:30:06 -07:00
memstick memstick: add support for legacy memorysticks 2013-09-11 15:59:35 -07:00
message
mfd Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
misc mei: cancel stall timers in mei_reset 2013-09-26 13:56:53 -07:00
mmc ARM: shmobile: update SDHI DT compatibility string to the <unit>-<soc> format 2013-09-21 09:55:32 -07:00
mtd mtd: nand: pxa3xx: Remove unneeded ifdef CONFIG_OF 2013-09-17 09:08:14 -07:00
net qlcnic: Fix SR-IOV configuration 2013-10-01 12:34:59 -04:00
nfc
ntb ntb: clean up unnecessary MSI/MSI-X capability find 2013-09-05 11:08:01 -07:00
nubus
of Merge branch 'for-v3.12-fix' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping 2013-09-11 19:11:59 -07:00
oprofile oprofile: get rid of pointless forward declarations of struct super_block 2013-09-03 22:52:48 -04:00
parisc PCI changes for the v3.12 merge window: 2013-09-03 16:24:35 -07:00
parport drivers: parport: Kconfig: exclude h8300 for PARPORT_PC 2013-08-30 12:08:04 -07:00
pci PCI: Workaround missing pci_set_master in pci drivers 2013-09-28 13:25:30 -07:00
pcmcia
pinctrl pinctrl: palmas: do not abort pin configuration for BIAS_DEFAULT 2013-09-27 16:22:43 +02:00
platform Merge branch 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86 2013-09-15 17:42:59 -04:00
pnp pnp: change pnp bus pm_ops to invoke pnp driver dev_pm_ops if specified 2013-09-11 15:58:15 -07:00
power Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
pps Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
ps3
ptp
pwm ARM: SoC cleanups for 3.12 2013-09-06 13:21:16 -07:00
rapidio
regulator Merge remote-tracking branch 'regulator/fix/wm8350' into regulator-linus 2013-09-30 12:04:33 +01:00
remoteproc
reset
rpmsg
rtc HID RTC: Open sensor hub open close 2013-10-01 22:06:15 +01:00
s390 s390/vmcore: use vmcore for zfcpdump 2013-09-11 15:59:15 -07:00
sbus
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-09-19 13:57:28 -05:00
sfi
sh
sn
spi Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
ssb
staging iio: Add reference counting for buffers 2013-10-12 12:04:01 +01:00
target iscsi-target; Allow an extra tag_num / 2 number of percpu_ida tags 2013-10-03 14:22:45 -07:00
tc
thermal drivers: thermal: add check when unregistering cpu cooling 2013-09-03 09:10:34 -04:00
tty xen/hvc: allow xenboot console to be used again 2013-10-03 16:12:58 -07:00
uio Driver core patches for 3.12-rc1 2013-09-03 11:37:15 -07:00
usb usb: chipidea: add Intel Clovertrail pci id 2013-10-03 15:41:54 -07:00
uwb
vfio vfio-pci: PCI hot reset interface 2013-09-04 11:28:04 -06:00
vhost vhost/scsi: Use GFP_ATOMIC with percpu_ida_alloc for obtaining tag 2013-10-01 21:27:31 -07:00
video video: mxsfb: Add missing break 2013-09-26 15:33:23 +03:00
virt
virtio virtio_pci: pm: Use CONFIG_PM_SLEEP instead of CONFIG_PM 2013-09-09 10:02:53 +09:30
vlynq
vme vme: vme_ca91cx42.c: fix to pass correct device identity to free_irq() 2013-08-27 21:49:26 -07:00
w1 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
watchdog Merge git://www.linux-watchdog.org/linux-watchdog 2013-09-12 08:45:53 -07:00
xen Bug-fixes: 2013-09-25 15:50:53 -07:00
zorro
Kconfig
Makefile