FOP_UNSIGNED_OFFSET abuse

[Dan Carpenter <error27@gmail.com>]

Is there a point to FOP_UNSIGNED_OFFSET now that everyone is on 64bit?
I thought the flag was for back in the day where we it was a huge deal
to access 4GB instead of 2GB.

It's mostly used in DRM.  drm_open_helper() forces you to set the flag
but drm_read() ignores the offset so I don't understand the point of
this.

regards,
dan carpenter

$ git grep FOP_UNSIGNED_OFFSET
drivers/accel/amdxdna/amdxdna_pci_drv.c:        .fop_flags      = FOP_UNSIGNED_OFFSET,
drivers/char/adi.c:     .fop_flags      = FOP_UNSIGNED_OFFSET,
drivers/char/mem.c:     .fop_flags      = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/adp/adp_drv.c:  .fop_flags      = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c:        .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/drm_file.c:     if (WARN_ON_ONCE(!(filp->f_op->fop_flags & FOP_UNSIGNED_OFFSET)))
drivers/gpu/drm/gma500/psb_drv.c:       .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/i915/i915_driver.c:     .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/nouveau/nouveau_drm.c:  .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/panthor/panthor_drv.c:  .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/radeon/radeon_drv.c:    .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/tegra/drm.c:    .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c:    .fop_flags = FOP_UNSIGNED_OFFSET,
drivers/gpu/drm/xe/xe_device.c: .fop_flags = FOP_UNSIGNED_OFFSET,
fs/proc/base.c: if (WARN_ON_ONCE(!(file->f_op->fop_flags & FOP_UNSIGNED_OFFSET)))
fs/proc/base.c: .fop_flags      = FOP_UNSIGNED_OFFSET,
fs/read_write.c:        return file->f_op->fop_flags & FOP_UNSIGNED_OFFSET;
include/drm/drm_accel.h:        .fop_flags      = FOP_UNSIGNED_OFFSET
include/drm/drm_gem.h:  .fop_flags      = FOP_UNSIGNED_OFFSET
include/drm/drm_gem_dma_helper.h:               .fop_flags = FOP_UNSIGNED_OFFSET, \
include/linux/fs.h:#define FOP_UNSIGNED_OFFSET  ((__force fop_flags_t)(1 << 5))
mm/mmap.c:      if (file->f_op->fop_flags & FOP_UNSIGNED_OFFSET)
rust/bindings/bindings_helper.h:const fop_flags_t RUST_CONST_HELPER_FOP_UNSIGNED_OFFSET = FOP_UNSIGNED_OFFSET;
rust/kernel/drm/gem/mod.rs:    fops.fop_flags = bindings::FOP_UNSIGNED_OFFSET;