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310,437 commits

Author SHA1 Message Date
Ricardo Neri
24ccfc5541 OMAPDSS: HDMI: OMAP4: Remap speaker order to match ALSA order
As of today, the only know user of the DSS HDMI audio support is
ASoC. Hence, it makes sense to remap the speaker order to match
the ALSA speaker order. In the future, a dynamic mapping mechanism
may be implemented.

Remapping is needed as the HDMI speaker order is FL/FR/LFE/C/RL/RR/
RLC-FLC/RRC-FLC while the ALSA order is FL/FR/RL/RR/C/LFE/SL/SR.
Refer to CEA-861 Section 6.6.2 for further details.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:17:09 +03:00
Ricardo Neri
6ec355d6c7 OMAPDSS: HDMI: Add an audio configuration function
The generic HDMI driver does not need to know about the specific
settings of a given IP. Hence, it just passes the audio configuration
and the IP library parses such configuration and sets the IP
accordingly. This patch introduces an IP-specific audio configuration
function.

Also, this patch implements the audio config function for OMAP4. The
DMA, format and core config functions are no longer exposed to the
generic HDMI driver as they are IP-specific.

The audio configuration function caters for 16-bit through 24-bit
audio samples with sample rates from 32kHz and up to 192kHz as well
as up to 8 audio channels.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:17:08 +03:00
Ricardo Neri
25a653597e OMAPDSS: HDMI: Add support for more audio sample rates in N/CTS calculation
Add support for more sample rates when calculating N and CTS. This
covers all the audio sample rates that an HDMI source is allowed
to transmit according to the HDMI 1.4a specification.

Also, reorganize the logic for the calculation when using deep color.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:17:08 +03:00
Ricardo Neri
35547626f3 OMAPDSS: HDMI: Relocate N/CTS calculation
The N and CTS parameters are relevant to all HDMI implementations and
not specific to a given IP. Hence, the calculation is relocated
into the generic HDMI driver.

Also, deep color is not queried but it is still considered in the
calculation of N. This is to be changed when deep color functionality is
implemented in the driver.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:17:06 +03:00
Ricardo Neri
c1164ed87e OMAPDSS: HDMI: OMAP4: Expand configuration for IEC-60958 audio
Utilize a snd_aes_iec958 struct to write the parameters of the IEC-60958
channel status word into the HDMI IP registers. Hence, the user of the
driver has full control of what parameters are written in the word.

Also, some of the parameters of the I2S structure have been removed
as they are actually IEC-60958 parameters.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:23 +03:00
Ricardo Neri
7e151f7f6a OMAPDSS: HDMI: Decouple HDMI audio from ASoC
Instead of having OMAPDSS HDMI audio functionality depending on the
ASoC HDMI audio driver, use a new config option so that
potential users, including ASoC, may select if needed.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:22 +03:00
Axel Castaneda Gonzalez
3df9fb5c51 OMAPDSS: HDMI: Decouple wrapper enable/disable and audio start/stop
Decouple the enable/disable operation of the HDMI audio wrapper from
audio start/stop. Otherwise, an audio FIFO underflow may occur. The
audio wrapper enablement must be done after configuration and
before audio playback is started.

Signed-off-by: Axel Castaneda Gonzalez <x0055901@ti.com>
Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:22 +03:00
Ricardo Neri
7c92af1678 OMAPDSS: HDMI: OMAP4: Remove invalid I2S settings
According to the most up-to-date documentation from Texas Instruments,
the configuration of High Bitrate Audio is not possible. Also, it is
not possible to set polarity of the I2S Word Select signal. This patch
removes the invalid settings.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:21 +03:00
Ricardo Neri
199e7fd621 OMAPDSS: HDMI: OMAP4: Remove CEA-861 audio infoframe and IEC-60958 enums
Instead of having its own definitions for CEA-861 and IEC-60958, the HDMI
driver should use those provided by ALSA. This patch removes the definitions
that are already provided by ALSA.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:21 +03:00
Ricardo Neri
7c3291f06b OMAPDSS: HDMI: Remove ASoC codec
Remove the ASoC OMAP HDMI audio codec. The goal of removing the codec
is to, in subsequent patches, give way to the implementation of the HDMI
audio support using the DSS device driver audio interface. This
approach will expose the HDMI audio functionality to any interested entity.

In a separate patch, ASoC will use this new approach to expose HDMI audio
to ALSA.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:15:18 +03:00
Ricardo Neri
c0456be38f OMAPDSS: HDMI: Split video_enable into video_enable/disable
To improve readability, split the video_enable HDMI IP operation
into two separate functions for enabling and disabling video.
The video_enable function is also modified to return an error value.

While there, update these operations for the OMAP4 IP accordingly.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:13:51 +03:00
Ricardo Neri
027bdc85ee OMAPDSS: HDMI: Split audio_enable into audio_enable/disable
To improve readability, split the audio_enable HDMI IP operation
into two separate functions for enabling and disabling audio.
The audio_enable function is also modified to return an error value.

While there, update these operations for the OMAP4 IP accordingly.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:13:50 +03:00
Ricardo Neri
9c0b842036 OMAPDSS: Provide an interface for audio support
There exist several display technologies and standards that support audio as
well. Hence, it is relevant to update the DSS device driver to provide an audio
interface that may be used by an audio driver or any other driver interested in
the functionality.

The audio_enable function is intended to prepare the relevant
IP for playback (e.g., enabling an audio FIFO, taking in/out of reset
some IP, enabling companion chips, etc). It is intended to be called before
audio_start. The audio_disable function performs the reverse operation and is
intended to be called after audio_stop.

While a given DSS device driver may support audio, it is possible that for
certain configurations audio is not supported (e.g., an HDMI display using a
VESA video timing). The audio_supported function is intended to query whether
the current configuration of the display supports audio.

The audio_config function is intended to configure all the relevant audio
parameters of the display. In order to make the function independent of any
specific DSS device driver, a struct omap_dss_audio is defined. Its purpose
is to contain all the required parameters for audio configuration. At the
moment, such structure contains pointers to IEC-60958 channel status word and
CEA-861 audio infoframe structures. This should be enough to support HDMI and
DisplayPort, as both are based on CEA-861 and IEC-60958. The omap_dss_audio
structure may be extended in the future if required.

The audio_enable/disable, audio_config and audio_supported functions could be
implemented as functions that may sleep. Hence, they should not be called
while holding a spinlock or a readlock.

The audio_start/audio_stop function is intended to effectively start/stop audio
playback after the configuration has taken place. These functions are designed
to be used in an atomic context. Hence, audio_start should return quickly and be
called only after all the needed resources for audio playback (audio FIFOs,
DMA channels, companion chips, etc) have been enabled to begin data transfers.
audio_stop is designed to only stop the audio transfers. The resources used
for playback are released using audio_disable.

A new enum omap_dss_audio_state is introduced to help the implementations of
the interface to keep track of the audio state. The initial state is _DISABLED;
then, the state transitions to _CONFIGURED, and then, when it is ready to
play audio, to _ENABLED. The state _PLAYING is used when the audio is being
rendered.

Signed-off-by: Ricardo Neri <ricardo.neri@ti.com>
2012-05-11 15:13:50 +03:00
Tomi Valkeinen
38137c8f0c Merge branch 'dss-devtree-cleanup'
Merge OMAP DSS cleanups that restructure the omapdss driver to facilitate
implementing device tree support in the future.
2012-05-11 15:10:10 +03:00
Russ Dill
af461d64e1 OMAPDSS: TFP410: use gpio_set_value_cansleep
The Beagleboard xM gpio used for TFP410 powerdown is connected through
an I2C attached chip which means setting the GPIO can sleep. Code that
calls tfp410_power_on/off holds a mutex, so sleeping should be fine.

Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 15:09:29 +03:00
Tomi Valkeinen
38f3daf678 OMAPDSS: separate pdata based initialization
Move the platform-data based display device initialization into a
separate function, so that we may later add of-based initialization.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 15:09:24 +03:00
Antonio Quartulli
35c133a000 batman-adv: add contributor name
translation_table.{c,h} have been heavily modified by another contributor and
for legal purposes it is better to include his name into the contributor list

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:08 +02:00
Antonio Quartulli
c64703aace batman-adv: update copyright years
update copyright years in order to include 2012

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:07 +02:00
Marek Lindner
fefa532971 batman-adv: fix checkpatch string complaint
Regression introduced by: f76d019194e0a88c57371df169ecc979690a04c2

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:06 +02:00
Marek Lindner
13b2541b11 batman-adv: avoid temporary routing loops by being strict on forwarded OGMs
batman-adv would forward OGMs from non-besthops while replacing the the TQ
and TTL values with the values from the best hop. In certain corner cases
this leads to a temporary routing loop.
This patch changes this behavior: Only packets from best next hops are
forwarded - TQ and TTL values won't be replaced anymore. However, the protocol
needs to rebroadcast OGMs from single hop neighbors regardless of whether or
not they are the best hop. To handle this case a new flag is introduced to
alert neighboring nodes about the forwarded OGM that is not from my best
next hop. It is to be discarded by all nodes except for the one originating
the OGM.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Daniele Furlan <daniele.furlan@gmail.com>
Tested-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
2012-05-11 13:56:05 +02:00
Linus Luessing
9d853f6246 batman-adv: Adding hard_iface specific sysfs wrapper macros for UINT
This allows us to easily add a sysfs parameter for an unsigned int
later, which is not for a batman mesh interface (e.g. bat0), but for a
common interface instead. It allows reading and writing an atomic_t in
hard_iface (instead of bat_priv compared to the mesh variant).

Developed by Linus during a 6 months trainee study period in Ascom
(Switzerland) AG.

Signed-off-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2012-05-11 13:56:03 +02:00
Marek Lindner
f245c38ba7 batman-adv: rename sysfs macros to reflect the soft-interface dependency
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:02 +02:00
Marek Lindner
c32293983d batman-adv: refactoring API: find generalized name for bat_ogm_update_mac callback
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:56:01 +02:00
Marek Lindner
edbf12ba56 batman-adv: ignore protocol packets if the interface did not enable this protocol
Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:55:59 +02:00
Marek Lindner
7ae8b2852f batman-adv: split neigh_new function into generic and batman iv specific parts
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2012-05-11 13:55:57 +02:00
Tomi Valkeinen
11ee960640 OMAPDSS: DSI: improve DSI module id handling
We currently use the id of the dsi platform device (dsidev->id) as the
DSI hardware module ID. This works because we assign the ID manually in
arch/arm/mach-omap2/display.c at boot time.

However, with device tree the platform device IDs are automatically
assigned to an arbitrary number, and we can't use it.

Instead of using dsidev->id during operation, this patch stores the
value of dsidev->id to a private field of the dsi driver at probe(). The
future device tree code can thus set the private field with some other
way.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:54:41 +03:00
Tomi Valkeinen
9d8232a77f OMAPDSS: init omap_dss_devices internally
Now that each output driver creates their own display devices, the
output drivers can also initialize those devices.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:54:38 +03:00
Tomi Valkeinen
35deca3de6 OMAPDSS: interface drivers register their panel devices
Currently the higher level omapdss platform driver gets the list of
displays in its platform data, and uses that list to create the
omap_dss_device for each display.

With DT, the logical way to do the above is to list the displays under
each individual output, i.e. we'd have "dpi" node, under which we would
have the display that uses DPI. In other words, each output driver
handles the displays that use that particular output.

To make the current code ready for DT, this patch modifies the output
drivers so that each of them creates the display devices which use that
output. However, instead of changing the platform data to suit this
method, each output driver is passed the full list of displays, and the
drivers pick the displays that are meant for them. This allows us to
keep the old platform data, and thus we avoid the need to change the
board files.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:52:23 +03:00
Tomi Valkeinen
c018c6738b OMAPDSS: change default_device handling
We currently have a two ways to set a "default panel device" for dss, to
which the overlays are connected when the omapdss driver is loaded:

- in textual format (name of the display) as cmdline parameter
- as a pointer to the panel device from board file via pdata

The current code handles this in a bit too complex way by using both of
the above methods during runtime. However, with DT we don't have pdata
anymore, so the code handling the second case won't work anymore. The
current code has also the problem that it modifies the platform_data.

This patch simplifies the code a bit by using the pointer method only
inside the probe function, and stores the name of the panel device. This
way we only need to handle the textual format during operation and also
avoid modifying the platform_data.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
d64f14e191 OMAPFB: add __init & __exit
Change omapfb to use platform_driver_probe and add __init & __exit.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
6e7e8f06b2 OMAPDSS: add __init & __exit
Now that we are using platform_driver_probe() we can add __inits and
__exits all around.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
61055d4b2e OMAPDSS: use platform_driver_probe for dsi/hdmi/rfbi/venc/dpi/sdi
Now that the core.c doesn't fail if output driver's init fails, we can
change the uses of platform_driver_register to platform_driver_probe.
This will allow us to use __init in the following patches.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
e40402cf18 OMAPDSS: move the creation of debugfs files
Instead of having an ugly #ifdef mess in the core.c for creating debugfs
files, add a dss_debugfs_create_file() function that the dss drivers
can use to create the debugfs files.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
461395c464 OMAPDSS: handle output-driver reg/unreg more dynamically
Initialize and uninitialize the output drivers by using arrays of
pointers to the init/uninit functions. This simplifies the code
slightly.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:52 +03:00
Tomi Valkeinen
852f083843 OMAPDSS: remove uses of dss_runtime_get/put
Now that the omapdss_core device is the parent for all other dss
devices, we don't need to use the dss_runtime_get/put anymore. Instead,
enabling omapdss_core will happen automatically when a child device is
enabled.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
a57dd4fe7b OMAPDSS: create DPI & SDI drivers
We currently have separate device/driver for each DSS HW module. The DPI
and SDI outputs are more or less parts of the DSS or DISPC hardware
modules, but in SW it makes sense to represent them as device/driver
pairs similarly to all the other outputs. This also makes sense for
device tree, as each node under dss will be a platform device, and
handling DPI & SDI somehow differently than the rest would just make the
code more complex.

This patch modifies the dpi.c and sdi.c to create drivers for the
platform devices.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
53f576a8dc OMAPDSS: create DPI & SDI devices
We currently have separate device/driver for each DSS HW module. The DPI
and SDI outputs are more or less parts of the DSS or DISPC hardware
modules, but in SW it makes sense to represent them as device/driver
pairs similarly to all the other outputs. This also makes sense for
device tree, as each node under dss will be a platform device, and
handling DPI & SDI somehow differently than the rest would just make the
code more complex.

This patch modifies arch/arm/mach-omap2/display.c to create platform
devices for DPI and SDI, and later patches will implement driver for
them.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
966eaed08c OMAPDSS: create custom pdevs for DSS omap_devices
Instead of using omap_device_build() to create the omap_devices for DSS
hwmods, create them with a custom function. This will allow us to create
a parent-child hierarchy for the devices so that the omapdss_core device
is parent for the rest of the dss hwmod devices.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
11436e1dd2 OMAPDSS: use platform_driver_probe for core/dispc/dss
The platform devices for omapdss, dss and dispc drivers are always
present, so we can use platform_driver_probe instead of
platform_driver_register.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
04c742c3dc OMAPDSS: remove return from platform_driver_unreg
For unknown reasons we seem to have a return in each of the omapdss's
uninit functions, which is a void function.

Remove the returns.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
00928eaf52 OMAPDSS: clean up the omapdss platform data mess
The omapdss pdata handling is a mess. This is more evident when trying
to use device tree for DSS, as we don't have platform data anymore in
that case. This patch cleans the pdata handling by:

- Remove struct omap_display_platform_data. It was used just as a
  wrapper for struct omap_dss_board_info.
- Pass the platform data only to omapdss device. The drivers for omap
  dss hwmods do not need the platform data. This should also work better
  for DT, as we can create omapdss device programmatically in generic omap
  boot code, and thus we can pass the pdata to it.
- Create dss functions for get_ctx_loss_count and dsi_enable/disable_pads
  that the dss hwmod drivers can call.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:51 +03:00
Tomi Valkeinen
e23d83b0c9 OMAPDSS: DSI: use dsi_get_dsidev_id(dsidev) instead of dsidev->id
The DSI driver uses dsi_get_dsidev_id() to get the ID number for the DSI
instance. However, there were a few places where dsidev->id was used
instead of the function. Fix those places to use the function.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:50 +03:00
Tomi Valkeinen
958f2717b8 OMAPDSS: TFP410: pdata rewrite
To ease device tree adaptation in the future, rewrite TFP410 platform
data handling to be done inside probe(), so that probe() is the only
place where we need to handle the DT/pdata choice.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:50 +03:00
Tomi Valkeinen
3a028bb99d OMAPFB: fix parsing of vram parameter
omapfb_parse_vram_param()'s check for end pointer returned from
simple_strtoul() is wrong, causing the code to bug if the second or
later vram parameters are non-parseable, for example
"omapfb.vram=0:2M,:5M".

However, even in that case the code will most likely bail out with
-EINVAL in the following checks, so the bug is probably not a fatal one.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reported-by: Hein Tibosch <hein_tibosch@yahoo.es>
2012-05-11 14:44:27 +03:00
Grazvydas Ignotas
b3e68d3065 OMAPDSS: OMAPFB: always allow to configure overlay
Currently when multiple overlays are active, OMAPFB_SETUP_PLANE fails.
Instead of failing, allow it to configure the first overlay as if there
was only one overlay, the remaining ones will have to be configured in
other ways (sysfs).

This allows overlay-controlling programs (like video players) to function
properly when framebuffer is cloned to another display (like TV).

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:21 +03:00
Grazvydas Ignotas
0aca3c63e0 OMAPDSS: VENC: allow switching venc output type at runtime
VENC output type (composite/svideo) doesn't have to be fixed by board
wiring, it is possible to also provide composite signal through svideo
luminance connector (software enabled), which is what pandora does.

Having to recompile the kernel for users who have TV connector types
that don't match default board setting is very inconvenient, especially
for users of a consumer device, so add support for switching VENC output
type at runtime over a new sysfs file output_type.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-05-11 14:44:13 +03:00
Bo Shen
b2522f9262 ALSA: atmel/ac97c: correct the unexpected behavior when using uninitial value for reset pin
When pdata->reset_pin is passed with a negative value (means gpio
is invalid), then chip->reset_pin will not be assigned to a vaule,
it will use default value 0. This will cause unexpected behavior.

So, add this patch to correct.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-05-11 12:10:04 +02:00
David Howells
fd75815f72 KEYS: Add invalidation support
Add support for invalidating a key - which renders it immediately invisible to
further searches and causes the garbage collector to immediately wake up,
remove it from keyrings and then destroy it when it's no longer referenced.

It's better not to do this with keyctl_revoke() as that marks the key to start
returning -EKEYREVOKED to searches when what is actually desired is to have the
key refetched.

To invalidate a key the caller must be granted SEARCH permission by the key.
This may be too strict.  It may be better to also permit invalidation if the
caller has any of READ, WRITE or SETATTR permission.

The primary use for this is to evict keys that are cached in special keyrings,
such as the DNS resolver or an ID mapper.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11 10:56:56 +01:00
David Howells
31d5a79d7f KEYS: Do LRU discard in full keyrings
Do an LRU discard in keyrings that are full rather than returning ENFILE.  To
perform this, a time_t is added to the key struct and updated by the creation
of a link to a key and by a key being found as the result of a search.  At the
completion of a successful search, the keyrings in the path between the root of
the search and the first found link to it also have their last-used times
updated.

Note that discarding a link to a key from a keyring does not necessarily
destroy the key as there may be references held by other places.

An alternate discard method that might suffice is to perform FIFO discard from
the keyring, using the spare 2-byte hole in the keylist header as the index of
the next link to be discarded.

This is useful when using a keyring as a cache for DNS results or foreign
filesystem IDs.


This can be tested by the following.  As root do:

	echo 1000 >/proc/sys/kernel/keys/root_maxkeys

	kr=`keyctl newring foo @s`
	for ((i=0; i<2000; i++)); do keyctl add user a$i a $kr; done

Without this patch ENFILE should be reported when the keyring fills up.  With
this patch, the keyring discards keys in an LRU fashion.  Note that the stored
LRU time has a granularity of 1s.

After doing this, /proc/key-users can be observed and should show that most of
the 2000 keys have been discarded:

	[root@andromeda ~]# cat /proc/key-users
	    0:   517 516/516 513/1000 5249/20000

The "513/1000" here is the number of quota-accounted keys present for this user
out of the maximum permitted.

In /proc/keys, the keyring shows the number of keys it has and the number of
slots it has allocated:

	[root@andromeda ~]# grep foo /proc/keys
	200c64c4 I--Q--     1 perm 3b3f0000     0     0 keyring   foo: 509/509

The maximum is (PAGE_SIZE - header) / key pointer size.  That's typically 509
on a 64-bit system and 1020 on a 32-bit system.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11 10:56:56 +01:00
David Howells
233e4735f2 KEYS: Permit in-place link replacement in keyring list
Make use of the previous patch that makes the garbage collector perform RCU
synchronisation before destroying defunct keys.  Key pointers can now be
replaced in-place without creating a new keyring payload and replacing the
whole thing as the discarded keys will not be destroyed until all currently
held RCU read locks are released.

If the keyring payload space needs to be expanded or contracted, then a
replacement will still need allocating, and the original will still have to be
freed by RCU.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-05-11 10:56:56 +01:00