| Message ID | 20220208104524.2516209-4-lucas.demarchi@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915/guc: Refactor ADS access to use iosys_map | expand |
On Tue, Feb 08, 2022 at 02:45:09AM -0800, Lucas De Marchi wrote: > Add a variant of shmem_read() that takes a iosys_map pointer rather > than a plain pointer as argument. It's mostly a copy __shmem_rw() but > adapting the api and removing the write support since there's currently > only need to use iosys_map as destination. > > Reworking __shmem_rw() to share the implementation was tempting, but > finding a good balance between reuse and clarity pushed towards a little > code duplication. Since the function is small, just add the similar > function with a copy/paste/adapt approach. > > v2: Add an offset as argument and instead of using a map iterator, use the > offset to keep track of where we are writing data to. > > Cc: Matt Roper <matthew.d.roper@intel.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Cc: David Airlie <airlied@linux.ie> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: Matthew Auld <matthew.auld@intel.com> > Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com> > Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> > --- > drivers/gpu/drm/i915/gt/shmem_utils.c | 32 +++++++++++++++++++++++++++ > drivers/gpu/drm/i915/gt/shmem_utils.h | 3 +++ > 2 files changed, 35 insertions(+) > > diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c > index 0683b27a3890..402f085f3a02 100644 > --- a/drivers/gpu/drm/i915/gt/shmem_utils.c > +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c > @@ -3,6 +3,7 @@ > * Copyright © 2020 Intel Corporation > */ > > +#include <linux/iosys-map.h> > #include <linux/mm.h> > #include <linux/pagemap.h> > #include <linux/shmem_fs.h> > @@ -123,6 +124,37 @@ static int __shmem_rw(struct file *file, loff_t off, > return 0; > } > > +int shmem_read_to_iosys_map(struct file *file, loff_t off, > + struct iosys_map *map, size_t map_off, size_t len) > +{ > + unsigned long pfn; > + > + for (pfn = off >> PAGE_SHIFT; len; pfn++) { > + unsigned int this = > + min_t(size_t, PAGE_SIZE - offset_in_page(off), len); > + struct page *page; > + void *vaddr; > + > + page = shmem_read_mapping_page_gfp(file->f_mapping, pfn, > + GFP_KERNEL); > + if (IS_ERR(page)) > + return PTR_ERR(page); > + > + vaddr = kmap(page); > + iosys_map_memcpy_to(map, map_off, vaddr + offset_in_page(off), > + this); > + mark_page_accessed(page); > + kunmap(page); > + put_page(page); > + > + len -= this; > + map_off += this; > + off = 0; > + } > + > + return 0; > +} > + > int shmem_read(struct file *file, loff_t off, void *dst, size_t len) > { > return __shmem_rw(file, off, dst, len, false); > diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.h b/drivers/gpu/drm/i915/gt/shmem_utils.h > index c1669170c351..b2b04d88c6e5 100644 > --- a/drivers/gpu/drm/i915/gt/shmem_utils.h > +++ b/drivers/gpu/drm/i915/gt/shmem_utils.h > @@ -8,6 +8,7 @@ > > #include <linux/types.h> > > +struct iosys_map; > struct drm_i915_gem_object; > struct file; > > @@ -17,6 +18,8 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj); > void *shmem_pin_map(struct file *file); > void shmem_unpin_map(struct file *file, void *ptr); > > +int shmem_read_to_iosys_map(struct file *file, loff_t off, > + struct iosys_map *map, size_t map_off, size_t len); > int shmem_read(struct file *file, loff_t off, void *dst, size_t len); > int shmem_write(struct file *file, loff_t off, void *src, size_t len); > > -- > 2.35.1 >
diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c index 0683b27a3890..402f085f3a02 100644 --- a/drivers/gpu/drm/i915/gt/shmem_utils.c +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c @@ -3,6 +3,7 @@ * Copyright © 2020 Intel Corporation */ +#include <linux/iosys-map.h> #include <linux/mm.h> #include <linux/pagemap.h> #include <linux/shmem_fs.h> @@ -123,6 +124,37 @@ static int __shmem_rw(struct file *file, loff_t off, return 0; } +int shmem_read_to_iosys_map(struct file *file, loff_t off, + struct iosys_map *map, size_t map_off, size_t len) +{ + unsigned long pfn; + + for (pfn = off >> PAGE_SHIFT; len; pfn++) { + unsigned int this = + min_t(size_t, PAGE_SIZE - offset_in_page(off), len); + struct page *page; + void *vaddr; + + page = shmem_read_mapping_page_gfp(file->f_mapping, pfn, + GFP_KERNEL); + if (IS_ERR(page)) + return PTR_ERR(page); + + vaddr = kmap(page); + iosys_map_memcpy_to(map, map_off, vaddr + offset_in_page(off), + this); + mark_page_accessed(page); + kunmap(page); + put_page(page); + + len -= this; + map_off += this; + off = 0; + } + + return 0; +} + int shmem_read(struct file *file, loff_t off, void *dst, size_t len) { return __shmem_rw(file, off, dst, len, false); diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.h b/drivers/gpu/drm/i915/gt/shmem_utils.h index c1669170c351..b2b04d88c6e5 100644 --- a/drivers/gpu/drm/i915/gt/shmem_utils.h +++ b/drivers/gpu/drm/i915/gt/shmem_utils.h @@ -8,6 +8,7 @@ #include <linux/types.h> +struct iosys_map; struct drm_i915_gem_object; struct file; @@ -17,6 +18,8 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj); void *shmem_pin_map(struct file *file); void shmem_unpin_map(struct file *file, void *ptr); +int shmem_read_to_iosys_map(struct file *file, loff_t off, + struct iosys_map *map, size_t map_off, size_t len); int shmem_read(struct file *file, loff_t off, void *dst, size_t len); int shmem_write(struct file *file, loff_t off, void *src, size_t len);
Add a variant of shmem_read() that takes a iosys_map pointer rather than a plain pointer as argument. It's mostly a copy __shmem_rw() but adapting the api and removing the write support since there's currently only need to use iosys_map as destination. Reworking __shmem_rw() to share the implementation was tempting, but finding a good balance between reuse and clarity pushed towards a little code duplication. Since the function is small, just add the similar function with a copy/paste/adapt approach. v2: Add an offset as argument and instead of using a map iterator, use the offset to keep track of where we are writing data to. Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> --- drivers/gpu/drm/i915/gt/shmem_utils.c | 32 +++++++++++++++++++++++++++ drivers/gpu/drm/i915/gt/shmem_utils.h | 3 +++ 2 files changed, 35 insertions(+)