On 04/04/2017 11:52 AM, Daniel Vetter wrote:
Also unify/merge with the existing stuff.
I was a bit torn where to put this, but in the end I decided to put all the ioctl/sysfs/debugfs stuff into drm-uapi.rst. That means we have a bit a split with the other uapi related stuff used internally, like drm_file.[hc], but I think overall this makes more sense.
If it's too confusing we can always add more cross-links to make it more discoverable. But the auto-sprinkling of links kernel-doc already does seems sufficient.
Also for prettier docs and more cross-links, switch the internal defines over to an enum, as usual.
v2: Update kerneldoc fro drm_compat_ioctl too (caught by 0day), plus a bit more drive-by polish.
v3: Fix typo, spotted by xerpi on irc (Sergi).
Cc: Sergi Granell xerpi.g.12@gmail.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com
Documentation/gpu/drm-internals.rst | 50 ---------------- Documentation/gpu/drm-uapi.rst | 14 +++++ drivers/gpu/drm/drm_ioc32.c | 76 ++++++++++++----------- drivers/gpu/drm/drm_ioctl.c | 50 +++++++++++++++- include/drm/drm_ioctl.h | 116 +++++++++++++++++++++++++++++++----- 5 files changed, 203 insertions(+), 103 deletions(-)
diff --git a/Documentation/gpu/drm-internals.rst b/Documentation/gpu/drm-internals.rst index a09c721f9e89..babfb6143bd9 100644 --- a/Documentation/gpu/drm-internals.rst +++ b/Documentation/gpu/drm-internals.rst @@ -255,56 +255,6 @@ File Operations .. kernel-doc:: drivers/gpu/drm/drm_file.c :export:
-IOCTLs
-struct drm_ioctl_desc *ioctls; int num_ioctls;
- Driver-specific ioctls descriptors table.
-Driver-specific ioctls numbers start at DRM_COMMAND_BASE. The ioctls -descriptors table is indexed by the ioctl number offset from the base -value. Drivers can use the DRM_IOCTL_DEF_DRV() macro to initialize -the table entries.
-::
- DRM_IOCTL_DEF_DRV(ioctl, func, flags)
-``ioctl`` is the ioctl name. Drivers must define the DRM_##ioctl and -DRM_IOCTL_##ioctl macros to the ioctl number offset from -DRM_COMMAND_BASE and the ioctl number respectively. The first macro is -private to the device while the second must be exposed to userspace in a -public header.
-``func`` is a pointer to the ioctl handler function compatible with the -``drm_ioctl_t`` type.
-::
- typedef int drm_ioctl_t(struct drm_device *dev, void *data,
struct drm_file *file_priv);-``flags`` is a bitmask combination of the following values. It restricts -how the ioctl is allowed to be called.
-- DRM_AUTH - Only authenticated callers allowed
-- DRM_MASTER - The ioctl can only be called on the master file handle
-- DRM_ROOT_ONLY - Only callers with the SYSADMIN capability allowed
-- DRM_CONTROL_ALLOW - The ioctl can only be called on a control
- device
-- DRM_UNLOCKED - The ioctl handler will be called without locking the
- DRM global mutex. This is the enforced default for kms drivers (i.e.
- using the DRIVER_MODESET flag) and hence shouldn't be used any more
- for new drivers.
-.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
- :export:
Misc Utilities
diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst index 8b0f0e403f0c..858457567d3d 100644 --- a/Documentation/gpu/drm-uapi.rst +++ b/Documentation/gpu/drm-uapi.rst @@ -160,6 +160,20 @@ other hand, a driver requires shared state between clients which is visible to user-space and accessible beyond open-file boundaries, they cannot support render nodes.
+IOCTL Support on Device Nodes +=============================
+.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
- :doc: driver specific ioctls
+.. kernel-doc:: include/drm/drm_ioctl.h
- :internal:
+.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
- :export:
+.. kernel-doc:: drivers/gpu/drm/drm_ioc32.c
- :export:
Testing and validation
diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c index b134482f4022..0fa7827cb0fd 100644 --- a/drivers/gpu/drm/drm_ioc32.c +++ b/drivers/gpu/drm/drm_ioc32.c @@ -1,4 +1,4 @@ -/** +/*
- \file drm_ioc32.c
- 32-bit ioctl compatibility routines for the DRM.
@@ -72,15 +72,15 @@ #define DRM_IOCTL_MODE_ADDFB232 DRM_IOWR(0xb8, drm_mode_fb_cmd232_t)
typedef struct drm_version_32 {
- int version_major; /**< Major version */
- int version_minor; /**< Minor version */
- int version_patchlevel; /**< Patch level */
- u32 name_len; /**< Length of name buffer */
- u32 name; /**< Name of driver */
- u32 date_len; /**< Length of date buffer */
- u32 date; /**< User-space buffer to hold date */
- u32 desc_len; /**< Length of desc buffer */
- u32 desc; /**< User-space buffer to hold desc */
- int version_major; /* Major version */
- int version_minor; /* Minor version */
- int version_patchlevel; /* Patch level */
- u32 name_len; /* Length of name buffer */
- u32 name; /* Name of driver */
- u32 date_len; /* Length of date buffer */
- u32 date; /* User-space buffer to hold date */
- u32 desc_len; /* Length of desc buffer */
- u32 desc; /* User-space buffer to hold desc */
} drm_version32_t;
static int compat_drm_version(struct file *file, unsigned int cmd, @@ -126,8 +126,8 @@ static int compat_drm_version(struct file *file, unsigned int cmd, }
typedef struct drm_unique32 {
- u32 unique_len; /**< Length of unique */
- u32 unique; /**< Unique name for driver instantiation */
- u32 unique_len; /* Length of unique */
- u32 unique; /* Unique name for driver instantiation */
} drm_unique32_t;
static int compat_drm_getunique(struct file *file, unsigned int cmd, @@ -180,12 +180,12 @@ static int compat_drm_setunique(struct file *file, unsigned int cmd, }
typedef struct drm_map32 {
- u32 offset; /**< Requested physical address (0 for SAREA)*/
- u32 size; /**< Requested physical size (bytes) */
- enum drm_map_type type; /**< Type of memory to map */
- enum drm_map_flags flags; /**< Flags */
- u32 handle; /**< User-space: "Handle" to pass to mmap() */
- int mtrr; /**< MTRR slot used */
- u32 offset; /* Requested physical address (0 for SAREA)*/
/\ Missing space here
- u32 size; /* Requested physical size (bytes) */
- enum drm_map_type type; /* Type of memory to map */
- enum drm_map_flags flags; /* Flags */
- u32 handle; /* User-space: "Handle" to pass to mmap() */
- int mtrr; /* MTRR slot used */
} drm_map32_t;
static int compat_drm_getmap(struct file *file, unsigned int cmd, @@ -286,12 +286,12 @@ static int compat_drm_rmmap(struct file *file, unsigned int cmd, }
typedef struct drm_client32 {
- int idx; /**< Which client desired? */
- int auth; /**< Is client authenticated? */
- u32 pid; /**< Process ID */
- u32 uid; /**< User ID */
- u32 magic; /**< Magic */
- u32 iocs; /**< Ioctl count */
- int idx; /* Which client desired? */
- int auth; /* Is client authenticated? */
- u32 pid; /* Process ID */
- u32 uid; /* User ID */
- u32 magic; /* Magic */
- u32 iocs; /* Ioctl count */
} drm_client32_t;
static int compat_drm_getclient(struct file *file, unsigned int cmd, @@ -366,12 +366,12 @@ static int compat_drm_getstats(struct file *file, unsigned int cmd, }
typedef struct drm_buf_desc32 {
- int count; /**< Number of buffers of this size */
- int size; /**< Size in bytes */
- int low_mark; /**< Low water mark */
- int high_mark; /**< High water mark */
- int count; /* Number of buffers of this size */
- int size; /* Size in bytes */
- int low_mark; /* Low water mark */
- int high_mark; /* High water mark */ int flags;
- u32 agp_start; /**< Start address in the AGP aperture */
- u32 agp_start; /* Start address in the AGP aperture */
} drm_buf_desc32_t;
static int compat_drm_addbufs(struct file *file, unsigned int cmd, @@ -1111,13 +1111,18 @@ static drm_ioctl_compat_t *drm_compat_ioctls[] = { };
/**
- Called whenever a 32-bit process running under a 64-bit kernel
- performs an ioctl on /dev/drm.
- drm_compat_ioctl - 32bit IOCTL compatibility handler for DRM drivers
- @filp: file this ioctl is called on
- @cmd: ioctl cmd number
- @arg: user argument
- Compatibility handler for 32 bit userspace running on 64 kernels. All actual
- IOCTL handling is forwarded to drm_ioctl(), while marshalling structures as
- appropriate. Note that this only handles DRM core IOCTLs, if the driver has
- botched IOCTL itself, it must handle those by wrapping this function.
- \param file_priv DRM file private.
- \param cmd command.
- \param arg user argument.
- \return zero on success or negative number on failure.
- Returns:
*/
- Zero on success, negative error code on failure.
long drm_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -1141,5 +1146,4 @@ long drm_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return ret; }
EXPORT_SYMBOL(drm_compat_ioctl); diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 7f4f4f48e390..f908ea94b784 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -647,13 +647,59 @@ static const struct drm_ioctl_desc drm_ioctls[] = { #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
/**
- DOC: driver specific ioctls
- First things first, driver private IOCTLs should only be needed for drivers
- supporting rendering. Kernel modesetting is all standardized, and extended
- through properties. There are a few exceptions in some existing drivers,
- which define IOCTL for use by the display DRM master, but they all predate
- properties.
- Now if you do have a render driver you always have to support it through
- driver private properties. There's a few steps needed to wire all the things
- up.
- First you need to define the structure for your IOCTL in your driver private
- UAPI header in ``include/uapi/drm/my_driver_drm.h``::
struct my_driver_operation {
u32 some_thing;
u32 another_thing;
};
- Please make sure that you follow all the best practices from
- ``Documentation/ioctl/botching-up-ioctls.txt``. Note that drm_ioctl()
- automatically zero-extends structures, hence make sure you can add more stuff
- at the end, i.e. don't put a variable sized array there.
- Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
- DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL_ prefix::
##define DRM_IOCTL_MY_DRIVER_OPERATION \
DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
- DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
- DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
- up the handlers and set the access rights:
static const struct drm_ioctl_desc my_driver_ioctls[] = {
DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
DRM_AUTH|DRM_RENDER_ALLOW),
};
- And then assign this to the &drm_driver.ioctls field in your driver
- structure.
- */
+/**
- drm_ioctl - ioctl callback implementation for DRM drivers
- @filp: file this ioctl is called on
- @cmd: ioctl cmd number
- @arg: user argument
- Looks up the ioctl function in the ::ioctls table, checking for root
- previleges if so required, and dispatches to the respective function.
- Looks up the ioctl function in the DRM core and the driver dispatch table,
- stored in &drm_driver.ioctls. It checks for necessary permission by calling
- drm_ioctl_permit(), and dispatches to the respective function.
- Returns:
- Zero on success, negative error code on failure.
diff --git a/include/drm/drm_ioctl.h b/include/drm/drm_ioctl.h index f17ee077f649..ee03b3c44b3b 100644 --- a/include/drm/drm_ioctl.h +++ b/include/drm/drm_ioctl.h @@ -33,6 +33,7 @@ #define _DRM_IOCTL_H_
#include <linux/types.h> +#include <linux/bitops.h>
#include <asm/ioctl.h>
@@ -41,41 +42,126 @@ struct drm_file; struct file;
/**
- Ioctl function type.
- drm_ioctl_t - DRM ioctl function type.
- @dev: DRM device inode
- @data: private pointer of the ioctl call
- @file_priv: DRM file this ioctl was made on
- \param inode device inode.
- \param file_priv DRM file private pointer.
- \param cmd command.
- \param arg argument.
- This is the DRM ioctl typedef. Note that drm_ioctl() has alrady copied @data
- into kernel-space, and will also copy it back, depending upon the read/write
*/
- settings in the ioctl command code.
typedef int drm_ioctl_t(struct drm_device *dev, void *data, struct drm_file *file_priv);
+/**
- drm_ioctl_compat_t - compatibility DRM ioctl function type.
- @filp: file pointer
- @cmd: ioctl command code
- @arg: DRM file this ioctl was made on
- Just a typedef to make declaring an array of compatibility handlers easier.
- New drivers shouldn't screw up the structure layout for their ioctl
- structures and hence never need this.
- */
typedef int drm_ioctl_compat_t(struct file *filp, unsigned int cmd, unsigned long arg);
#define DRM_IOCTL_NR(n) _IOC_NR(n) #define DRM_MAJOR 226
-#define DRM_AUTH 0x1 -#define DRM_MASTER 0x2 -#define DRM_ROOT_ONLY 0x4 -#define DRM_CONTROL_ALLOW 0x8 -#define DRM_UNLOCKED 0x10 -#define DRM_RENDER_ALLOW 0x20 +/**
- enum drm_ioctl_flags - DRM ioctl flags
- Various flags that can be set in &drm_ioctl_desc.flags to control how
- userspace can use a given ioctl.
- */
+enum drm_ioctl_flags {
- /**
* @DRM_AUTH:** This is for ioctl which are used for rendering, and require that the* file descriptor is either for a render node, or if it's a* legacy/primary node, then it must be authenticated.*/- DRM_AUTH = BIT(0),
- /**
* @DRM_MASTER:** This must be set for any ioctl which can change the modeset or* display state. Userspace must call the ioctl through a primary node,* while it is the active master.** Note that read-only modeset ioctl can also be called by* unauthenticated clients, or when a master is not the currently active* one.*/- DRM_MASTER = BIT(1),
- /**
* @DRM_ROOT_ONLY:** Anything that could potentially wreak a master file descriptor needs* to have this flag set. Current that's only for the SETMASTER and* DROPMASTER ioctl, which e.g. logind can call to force a non-behaving* master (display compositor) into compliance.** This is equivalent to callers with the SYSADMIN capability.*/- DRM_ROOT_ONLY = BIT(2),
- /**
* @DRM_CONTROL_ALLOW:** Deprecated, do not use. Control nodes are in the process of getting* removed.*/- DRM_CONTROL_ALLOW = BIT(3),
- /**
* @DRM_UNLOCKED:** Whether &drm_ioctl_desc.func should be called with the DRM BKL held* or not. Enforced as the default for all modern drivers, hence there* should never be a need to set this flag.*/- DRM_UNLOCKED = BIT(4),
- /**
* @DRM_RENDER_ALLOW:** This is used for all ioctl needed for rendering only, for drivers* which support render nodes. This should be all new render drivers,* and hence it should be always set for any ioctl with DRM_AUTH set.* Note though that read-only query ioctl might have this set, but have* not set DRM_AUTH because they do not require authentication.*/- DRM_RENDER_ALLOW = BIT(5),
+};
+/**
- struct drm_ioctl_desc - DRM driver ioctl entry
- @cmd: ioctl command number, without flags
- @flags: a bitmask of &enum drm_ioctl_flags
- @func: handler for this ioctl
- @name: user-readable name for debug output
- For convenience it's easier to create these using the DRM_IOCTL_DEF_DRV()
- macro.
- */
struct drm_ioctl_desc { unsigned int cmd;
- int flags;
- enum drm_ioctl_flags flags; drm_ioctl_t *func; const char *name;
};
/**
- Creates a driver or general drm_ioctl_desc array entry for the given
- ioctl, for use by drm_ioctl().
- DRM_IOCTL_DEF_DRV() - helper macro to fill out a &struct drm_ioctl_desc
- @ioctl: ioctl command suffix
- @_func: handler for the ioctl
- @_flags: a bitmask of &enum drm_ioctl_flags
- Small helper macro to create a &struct drm_ioctl_desc entry. The ioctl
- command number is constructed by prepending ``DRM_IOCTL_`` and passing that
*/
- to DRM_IOCTL_NR().
#define DRM_IOCTL_DEF_DRV(ioctl, _func, _flags) \ [DRM_IOCTL_NR(DRM_IOCTL_##ioctl) - DRM_COMMAND_BASE] = { \ .cmd = DRM_IOCTL_##ioctl, \
Reviewed-by: Neil Armstrong narmstrong@baylibre.com