23 Dec, 2011

2 commits

  • i810 uses a userspace provided mmio map using the drm core map
    infrastructure. By the time we reach lastclose, this is all gone
    and our mmio_map pointer points at freed memory. Depending upon
    luck that still works, most often it just oopses.

    Aside: drm maps aren't refcounted, so userspace can essentially oops
    the kernel any time it wants to. Who cares.

    Signed-off-by: Daniel Vetter

    Daniel Vetter
     
  • My dear old i815 always hits the deadlocked on reclaim_buffers
    warning. Switch over to the idlelock duct-tape on hope that
    works better. I've fired up my i815 and now closing glxgears doesn't
    take 5 seconds anymore. \o/

    Signed-off-by: Daniel Vetter

    Daniel Vetter
     

11 Nov, 2011

1 commit

  • From fdf1fdebaa00f81de18c227f32f8074c8b352d50 Mon Sep 17 00:00:00 2001
    From: Arjan van de Ven
    Date: Sun, 30 Oct 2011 19:06:07 -0700
    Subject: [PATCH] drm: Make the per-driver file_operations struct const

    The DRM layer keeps a copy of struct file_operations inside its
    big driver struct... which prevents it from being consistent and static.
    For consistency (and the general security objective of having such things
    static), it's desirable to get this fixed.

    This patch splits out the file_operations field to its own struct,
    which is then "static const", and just stick a pointer to this into
    the driver struct, making it more consistent with how the rest of the
    kernel does this.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Dave Airlie

    Arjan van de Ven
     

01 Nov, 2011

1 commit


07 Feb, 2011

2 commits

  • This abstracts the pci/platform interface out a step further,
    we can go further but this is far enough for now to allow USB
    to be plugged in.

    The drivers now just call the init code directly for their
    device type.

    Signed-off-by: Dave Airlie

    Dave Airlie
     
  • SMP i810 systems were practically nonexistent and the configuration
    was not officially supported by Intel at the time when Pentium-III
    was common.

    With this change, it is still possible to build a distribution kernel
    that has support for SMP and includes the i810 driver without the BKL.
    As a precaution, check for the theoretical SMP case at run time and
    refuse to load the driver.

    We also need to disable CONFIG_PREEMPT builds for this driver.

    Signed-off-by: Arnd Bergmann
    Cc: dri-devel@lists.freedesktop.org
    Signed-off-by: Dave Airlie

    Arnd Bergmann
     

27 Oct, 2010

1 commit

  • * 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (476 commits)
    vmwgfx: Implement a proper GMR eviction mechanism
    drm/radeon/kms: fix r6xx/7xx 1D tiling CS checker v2
    drm/radeon/kms: properly compute group_size on 6xx/7xx
    drm/radeon/kms: fix 2D tile height alignment in the r600 CS checker
    drm/radeon/kms/evergreen: set the clear state to the blit state
    drm/radeon/kms: don't poll dac load detect.
    gpu: Add Intel GMA500(Poulsbo) Stub Driver
    drm/radeon/kms: MC vram map needs to be >= pci aperture size
    drm/radeon/kms: implement display watermark support for evergreen
    drm/radeon/kms/evergreen: add some additional safe regs v2
    drm/radeon/r600: fix tiling issues in CS checker.
    drm/i915: Move gpu_write_list to per-ring
    drm/i915: Invalidate the to-ring, flush the old-ring when updating domains
    drm/i915/ringbuffer: Write the value passed in to the tail register
    agp/intel: Restore valid PTE bit for Sandybridge after bdd3072
    drm/i915: Fix flushing regression from 9af90d19f
    drm/i915/sdvo: Remove unused encoding member
    i915: enable AVI infoframe for intel_hdmi.c [v4]
    drm/i915: Fix current fb blocking for page flip
    drm/i915: IS_IRONLAKE is synonymous with gen == 5
    ...

    Fix up conflicts in
    - drivers/gpu/drm/i915/{i915_gem.c, i915/intel_overlay.c}: due to the
    new simplified stack-based kmap_atomic() interface
    - drivers/gpu/drm/vmwgfx/vmwgfx_drv.c: added .llseek entry due to BKL
    removal cleanups.

    Linus Torvalds
     

23 Oct, 2010

1 commit

  • * 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
    vfs: make no_llseek the default
    vfs: don't use BKL in default_llseek
    llseek: automatically add .llseek fop
    libfs: use generic_file_llseek for simple_attr
    mac80211: disallow seeks in minstrel debug code
    lirc: make chardev nonseekable
    viotape: use noop_llseek
    raw: use explicit llseek file operations
    ibmasmfs: use generic_file_llseek
    spufs: use llseek in all file operations
    arm/omap: use generic_file_llseek in iommu_debug
    lkdtm: use generic_file_llseek in debugfs
    net/wireless: use generic_file_llseek in debugfs
    drm: use noop_llseek

    Linus Torvalds
     

15 Oct, 2010

1 commit

  • All file_operations should get a .llseek operation so we can make
    nonseekable_open the default for future file operations without a
    .llseek pointer.

    The three cases that we can automatically detect are no_llseek, seq_lseek
    and default_llseek. For cases where we can we can automatically prove that
    the file offset is always ignored, we use noop_llseek, which maintains
    the current behavior of not returning an error from a seek.

    New drivers should normally not use noop_llseek but instead use no_llseek
    and call nonseekable_open at open time. Existing drivers can be converted
    to do the same when the maintainer knows for certain that no user code
    relies on calling seek on the device file.

    The generated code is often incorrectly indented and right now contains
    comments that clarify for each added line why a specific variant was
    chosen. In the version that gets submitted upstream, the comments will
    be gone and I will manually fix the indentation, because there does not
    seem to be a way to do that using coccinelle.

    Some amount of new code is currently sitting in linux-next that should get
    the same modifications, which I will do at the end of the merge window.

    Many thanks to Julia Lawall for helping me learn to write a semantic
    patch that does all this.

    ===== begin semantic patch =====
    // This adds an llseek= method to all file operations,
    // as a preparation for making no_llseek the default.
    //
    // The rules are
    // - use no_llseek explicitly if we do nonseekable_open
    // - use seq_lseek for sequential files
    // - use default_llseek if we know we access f_pos
    // - use noop_llseek if we know we don't access f_pos,
    // but we still want to allow users to call lseek
    //
    @ open1 exists @
    identifier nested_open;
    @@
    nested_open(...)
    {

    }

    @ open exists@
    identifier open_f;
    identifier i, f;
    identifier open1.nested_open;
    @@
    int open_f(struct inode *i, struct file *f)
    {

    }

    @ read disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {

    }

    @ read_no_fpos disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ write @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {

    }

    @ write_no_fpos @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ fops0 @
    identifier fops;
    @@
    struct file_operations fops = {
    ...
    };

    @ has_llseek depends on fops0 @
    identifier fops0.fops;
    identifier llseek_f;
    @@
    struct file_operations fops = {
    ...
    .llseek = llseek_f,
    ...
    };

    @ has_read depends on fops0 @
    identifier fops0.fops;
    identifier read_f;
    @@
    struct file_operations fops = {
    ...
    .read = read_f,
    ...
    };

    @ has_write depends on fops0 @
    identifier fops0.fops;
    identifier write_f;
    @@
    struct file_operations fops = {
    ...
    .write = write_f,
    ...
    };

    @ has_open depends on fops0 @
    identifier fops0.fops;
    identifier open_f;
    @@
    struct file_operations fops = {
    ...
    .open = open_f,
    ...
    };

    // use no_llseek if we call nonseekable_open
    ////////////////////////////////////////////
    @ nonseekable1 depends on !has_llseek && has_open @
    identifier fops0.fops;
    identifier nso ~= "nonseekable_open";
    @@
    struct file_operations fops = {
    ... .open = nso, ...
    +.llseek = no_llseek, /* nonseekable */
    };

    @ nonseekable2 depends on !has_llseek @
    identifier fops0.fops;
    identifier open.open_f;
    @@
    struct file_operations fops = {
    ... .open = open_f, ...
    +.llseek = no_llseek, /* open uses nonseekable */
    };

    // use seq_lseek for sequential files
    /////////////////////////////////////
    @ seq depends on !has_llseek @
    identifier fops0.fops;
    identifier sr ~= "seq_read";
    @@
    struct file_operations fops = {
    ... .read = sr, ...
    +.llseek = seq_lseek, /* we have seq_read */
    };

    // use default_llseek if there is a readdir
    ///////////////////////////////////////////
    @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier readdir_e;
    @@
    // any other fop is used that changes pos
    struct file_operations fops = {
    ... .readdir = readdir_e, ...
    +.llseek = default_llseek, /* readdir is present */
    };

    // use default_llseek if at least one of read/write touches f_pos
    /////////////////////////////////////////////////////////////////
    @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read.read_f;
    @@
    // read fops use offset
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = default_llseek, /* read accesses f_pos */
    };

    @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ... .write = write_f, ...
    + .llseek = default_llseek, /* write accesses f_pos */
    };

    // Use noop_llseek if neither read nor write accesses f_pos
    ///////////////////////////////////////////////////////////

    @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    identifier write_no_fpos.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ...
    .write = write_f,
    .read = read_f,
    ...
    +.llseek = noop_llseek, /* read and write both use no f_pos */
    };

    @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write_no_fpos.write_f;
    @@
    struct file_operations fops = {
    ... .write = write_f, ...
    +.llseek = noop_llseek, /* write uses no f_pos */
    };

    @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    @@
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = noop_llseek, /* read uses no f_pos */
    };

    @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    @@
    struct file_operations fops = {
    ...
    +.llseek = noop_llseek, /* no read or write fn */
    };
    ===== End semantic patch =====

    Signed-off-by: Arnd Bergmann
    Cc: Julia Lawall
    Cc: Christoph Hellwig

    Arnd Bergmann
     

06 Oct, 2010

1 commit


30 Sep, 2010

1 commit

  • The i810 and i830 device drivers may replace their file operations
    on an open file descriptor. My previous patch to move the BKL
    out of the common DRM code into these drivers only caught the
    default file operations, not the ones that actually end up being
    used.

    Found while trying to come up with a way to kill the BKL for
    good in these drivers.

    Signed-off-by: Arnd Bergmann
    Signed-off-by: Dave Airlie

    Arnd Bergmann
     

16 Sep, 2010

1 commit

  • The drm device drivers currently allow seeking on the
    character device but never care about the actual
    file position.

    When we change the default llseek operation to be
    no_llseek, calling llseek on a drm device would
    return an error condition, which is an API change.

    Explicitly setting noop_llseek lets us keep the
    current API.

    Signed-off-by: Arnd Bergmann
    Cc: David Airlie
    Cc: dri-devel@lists.freedesktop.org

    Arnd Bergmann
     

30 Aug, 2010

2 commits


17 Aug, 2010

1 commit

  • With the current screwed but its ABI, ioctls for the drm, Linus pointed out that we could allow userspace to specify the allocation size, but we pass it to the driver which then uses it blindly to store a struct. Now if userspace specifies the allocation size as smaller than the driver needs, the driver can possibly overwrite memory.

    This patch restructures the driver ioctls so we store the structure size we are expecting, and make sure we allocate at least that size. The copy from/to userspace are still restricted to the size the user specifies, this allows ioctl structs to grow on both sides of the equation.

    Up until now we didn't really use the DRM_IOCTL defines in the kernel, so this cleans them up and adds them for nouveau.

    v2:
    fix nouveau pushbuf arg (thanks to Ben for pointing it out)

    Reported-by: Linus Torvalds
    Signed-off-by: Dave Airlie

    Dave Airlie
     

05 Aug, 2010

1 commit

  • This restricts the use of the big kernel lock to the i830 and i810
    device drivers. The three remaining users in common code (open, ioctl
    and release) get converted to a new mutex, the drm_global_mutex,
    making the locking stricter than the big kernel lock.

    This may have a performance impact, but only in those cases that
    currently don't use DRM_UNLOCKED flag in the ioctl list and would
    benefit from that anyway.

    The reason why i810 and i830 cannot use drm_global_mutex in their
    mmap functions is a lock-order inversion problem between the current
    use of the BKL and mmap_sem in these drivers. Since the BKL has
    release-on-sleep semantics, it's harmless but it would cause trouble
    if we replace the BKL with a mutex.

    Instead, these drivers get their own ioctl wrappers that take the
    BKL around every ioctl call and then set their own handlers as
    DRM_UNLOCKED.

    Signed-off-by: Arnd Bergmann
    Cc: David Airlie
    Cc: dri-devel@lists.freedesktop.org
    Signed-off-by: Dave Airlie

    Arnd Bergmann
     

02 Aug, 2010

1 commit


30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

18 Dec, 2009

1 commit

  • drm_ioctl is called with the Big Kernel Lock held,
    which shows up very high in statistics on vfs_ioctl.

    Moving the lock into the drm_ioctl function itself
    makes sure we blame the right subsystem and it gets
    us one step closer to eliminating the locked version
    of fops->ioctl.

    Since drm_ioctl does not require the lock itself,
    we only need to hold it while calling the specific
    handler. The 32 bit conversion handlers do not
    interact with any other code, so they don't need
    the BKL here either and can just call drm_ioctl.

    As a bonus, this cleans up all the other users
    of drm_ioctl which now no longer have to find
    the inode or call lock_kernel.

    [airlied: squashed the non-driver bits
    of the second patch in here, this provides
    the flag for drivers to use to select unlocked
    ioctls - but doesn't modify any drivers].

    Signed-off-by: Arnd Bergmann
    Cc: David Airlie
    Cc: dri-devel@lists.sourceforge.net
    Cc: Frederic Weisbecker
    Cc: Thomas Gleixner
    Signed-off-by: Dave Airlie

    Arnd Bergmann
     

19 Jun, 2009

1 commit


13 Mar, 2009

1 commit

  • Once upon a time, the DRM made the distinction between the drm_map
    data structure exchanged with user space and the drm_local_map used
    in the kernel.

    For some reasons, while the BSD port still has that "feature", the
    linux part abused drm_map for kernel internal usage as the local
    map only existed as a typedef of the struct drm_map.

    This patch fixes it by declaring struct drm_local_map separately
    (though its content is currently identical to the userspace variant),
    and changing the kernel code to only use that, except when it's a
    userkernel interface (ie. ioctl).

    This allows subsequent changes to the in-kernel format

    I've also replaced the use of drm_local_map_t with struct drm_local_map
    in a couple of places. Mostly by accident but they are the same (the
    former is a typedef of the later) and I have some remote plans and
    half finished patch to completely kill the drm_local_map_t typedef
    so I left those bits in.

    Signed-off-by: Benjamin Herrenschmidt
    Acked-by: Eric Anholt
    Signed-off-by: Dave Airlie

    Benjamin Herrenschmidt
     

14 Jul, 2008

1 commit

  • With the coming of kernel based modesetting and the memory manager stuff,
    the everything in one directory approach was getting very ugly and
    starting to be unmanageable.

    This restructures the drm along the lines of other kernel components.

    It creates a drivers/gpu/drm directory and moves the hw drivers into
    subdirectores. It moves the includes into an include/drm, and
    sets up the unifdef for the userspace headers we should be exporting.

    Signed-off-by: Dave Airlie

    Dave Airlie