diff mbox series

[14/29] fsdax: simplify the pgoff calculation

Message ID 20211109083309.584081-15-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/29] nvdimm/pmem: move dax_attribute_group from dax to pmem | expand

Commit Message

Christoph Hellwig Nov. 9, 2021, 8:32 a.m. UTC
Replace the two steps of dax_iomap_sector and bdev_dax_pgoff with a
single dax_iomap_pgoff helper that avoids lots of cumbersome sector
conversions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/dax/super.c | 14 --------------
 fs/dax.c            | 35 ++++++++++-------------------------
 include/linux/dax.h |  1 -
 3 files changed, 10 insertions(+), 40 deletions(-)

Comments

Dan Williams Nov. 23, 2021, 7:44 p.m. UTC | #1
On Tue, Nov 9, 2021 at 12:33 AM Christoph Hellwig <hch@lst.de> wrote:
>
> Replace the two steps of dax_iomap_sector and bdev_dax_pgoff with a
> single dax_iomap_pgoff helper that avoids lots of cumbersome sector
> conversions.

Looks good,

Reviewed-by: Dan Williams <dan.j.williams@intel.com>

>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/dax/super.c | 14 --------------
>  fs/dax.c            | 35 ++++++++++-------------------------
>  include/linux/dax.h |  1 -
>  3 files changed, 10 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/dax/super.c b/drivers/dax/super.c
> index 803942586d1b6..c0910687fbcb2 100644
> --- a/drivers/dax/super.c
> +++ b/drivers/dax/super.c
> @@ -67,20 +67,6 @@ void dax_remove_host(struct gendisk *disk)
>  }
>  EXPORT_SYMBOL_GPL(dax_remove_host);
>
> -int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
> -               pgoff_t *pgoff)
> -{
> -       sector_t start_sect = bdev ? get_start_sect(bdev) : 0;
> -       phys_addr_t phys_off = (start_sect + sector) * 512;
> -
> -       if (pgoff)
> -               *pgoff = PHYS_PFN(phys_off);
> -       if (phys_off % PAGE_SIZE || size % PAGE_SIZE)
> -               return -EINVAL;
> -       return 0;
> -}
> -EXPORT_SYMBOL(bdev_dax_pgoff);
> -
>  /**
>   * dax_get_by_host() - temporary lookup mechanism for filesystem-dax
>   * @bdev: block device to find a dax_device for
> diff --git a/fs/dax.c b/fs/dax.c
> index e51b4129d1b65..5364549d67a48 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -709,23 +709,22 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
>         return __dax_invalidate_entry(mapping, index, false);
>  }
>
> -static sector_t dax_iomap_sector(const struct iomap *iomap, loff_t pos)
> +static pgoff_t dax_iomap_pgoff(const struct iomap *iomap, loff_t pos)
>  {
> -       return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
> +       phys_addr_t paddr = iomap->addr + (pos & PAGE_MASK) - iomap->offset;
> +
> +       if (iomap->bdev)
> +               paddr += (get_start_sect(iomap->bdev) << SECTOR_SHIFT);
> +       return PHYS_PFN(paddr);
>  }
>
>  static int copy_cow_page_dax(struct vm_fault *vmf, const struct iomap_iter *iter)
>  {
> -       sector_t sector = dax_iomap_sector(&iter->iomap, iter->pos);
> +       pgoff_t pgoff = dax_iomap_pgoff(&iter->iomap, iter->pos);
>         void *vto, *kaddr;
> -       pgoff_t pgoff;
>         long rc;
>         int id;
>
> -       rc = bdev_dax_pgoff(iter->iomap.bdev, sector, PAGE_SIZE, &pgoff);
> -       if (rc)
> -               return rc;
> -
>         id = dax_read_lock();
>         rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, &kaddr, NULL);
>         if (rc < 0) {
> @@ -1013,14 +1012,10 @@ EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
>  static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,
>                          pfn_t *pfnp)
>  {
> -       const sector_t sector = dax_iomap_sector(iomap, pos);
> -       pgoff_t pgoff;
> +       pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>         int id, rc;
>         long length;
>
> -       rc = bdev_dax_pgoff(iomap->bdev, sector, size, &pgoff);
> -       if (rc)
> -               return rc;
>         id = dax_read_lock();
>         length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
>                                    NULL, pfnp);
> @@ -1129,7 +1124,7 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
>  s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
>  {
>         sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
> -       pgoff_t pgoff;
> +       pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>         long rc, id;
>         void *kaddr;
>         bool page_aligned = false;
> @@ -1140,10 +1135,6 @@ s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
>             (size == PAGE_SIZE))
>                 page_aligned = true;
>
> -       rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
> -       if (rc)
> -               return rc;
> -
>         id = dax_read_lock();
>
>         if (page_aligned)
> @@ -1169,7 +1160,6 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>         const struct iomap *iomap = &iomi->iomap;
>         loff_t length = iomap_length(iomi);
>         loff_t pos = iomi->pos;
> -       struct block_device *bdev = iomap->bdev;
>         struct dax_device *dax_dev = iomap->dax_dev;
>         loff_t end = pos + length, done = 0;
>         ssize_t ret = 0;
> @@ -1203,9 +1193,8 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>         while (pos < end) {
>                 unsigned offset = pos & (PAGE_SIZE - 1);
>                 const size_t size = ALIGN(length + offset, PAGE_SIZE);
> -               const sector_t sector = dax_iomap_sector(iomap, pos);
> +               pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>                 ssize_t map_len;
> -               pgoff_t pgoff;
>                 void *kaddr;
>
>                 if (fatal_signal_pending(current)) {
> @@ -1213,10 +1202,6 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>                         break;
>                 }
>
> -               ret = bdev_dax_pgoff(bdev, sector, size, &pgoff);
> -               if (ret)
> -                       break;
> -
>                 map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
>                                 &kaddr, NULL);
>                 if (map_len < 0) {
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 439c3c70e347b..324363b798ecd 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -107,7 +107,6 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
>  #endif
>
>  struct writeback_control;
> -int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
>  #if IS_ENABLED(CONFIG_FS_DAX)
>  int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
>  void dax_remove_host(struct gendisk *disk);
> --
> 2.30.2
>
Darrick J. Wong Nov. 23, 2021, 10:36 p.m. UTC | #2
On Tue, Nov 09, 2021 at 09:32:54AM +0100, Christoph Hellwig wrote:
> Replace the two steps of dax_iomap_sector and bdev_dax_pgoff with a
> single dax_iomap_pgoff helper that avoids lots of cumbersome sector
> conversions.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/dax/super.c | 14 --------------
>  fs/dax.c            | 35 ++++++++++-------------------------
>  include/linux/dax.h |  1 -
>  3 files changed, 10 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/dax/super.c b/drivers/dax/super.c
> index 803942586d1b6..c0910687fbcb2 100644
> --- a/drivers/dax/super.c
> +++ b/drivers/dax/super.c
> @@ -67,20 +67,6 @@ void dax_remove_host(struct gendisk *disk)
>  }
>  EXPORT_SYMBOL_GPL(dax_remove_host);
>  
> -int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
> -		pgoff_t *pgoff)
> -{
> -	sector_t start_sect = bdev ? get_start_sect(bdev) : 0;
> -	phys_addr_t phys_off = (start_sect + sector) * 512;
> -
> -	if (pgoff)
> -		*pgoff = PHYS_PFN(phys_off);
> -	if (phys_off % PAGE_SIZE || size % PAGE_SIZE)

AFAICT, we're relying on fs_dax_get_by_bdev to have validated this
previously, which is why the error return stuff goes away?

If so,
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D


> -		return -EINVAL;
> -	return 0;
> -}
> -EXPORT_SYMBOL(bdev_dax_pgoff);
> -
>  /**
>   * dax_get_by_host() - temporary lookup mechanism for filesystem-dax
>   * @bdev: block device to find a dax_device for
> diff --git a/fs/dax.c b/fs/dax.c
> index e51b4129d1b65..5364549d67a48 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -709,23 +709,22 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
>  	return __dax_invalidate_entry(mapping, index, false);
>  }
>  
> -static sector_t dax_iomap_sector(const struct iomap *iomap, loff_t pos)
> +static pgoff_t dax_iomap_pgoff(const struct iomap *iomap, loff_t pos)
>  {
> -	return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
> +	phys_addr_t paddr = iomap->addr + (pos & PAGE_MASK) - iomap->offset;
> +
> +	if (iomap->bdev)
> +		paddr += (get_start_sect(iomap->bdev) << SECTOR_SHIFT);
> +	return PHYS_PFN(paddr);
>  }
>  
>  static int copy_cow_page_dax(struct vm_fault *vmf, const struct iomap_iter *iter)
>  {
> -	sector_t sector = dax_iomap_sector(&iter->iomap, iter->pos);
> +	pgoff_t pgoff = dax_iomap_pgoff(&iter->iomap, iter->pos);
>  	void *vto, *kaddr;
> -	pgoff_t pgoff;
>  	long rc;
>  	int id;
>  
> -	rc = bdev_dax_pgoff(iter->iomap.bdev, sector, PAGE_SIZE, &pgoff);
> -	if (rc)
> -		return rc;
> -
>  	id = dax_read_lock();
>  	rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, &kaddr, NULL);
>  	if (rc < 0) {
> @@ -1013,14 +1012,10 @@ EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
>  static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,
>  			 pfn_t *pfnp)
>  {
> -	const sector_t sector = dax_iomap_sector(iomap, pos);
> -	pgoff_t pgoff;
> +	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>  	int id, rc;
>  	long length;
>  
> -	rc = bdev_dax_pgoff(iomap->bdev, sector, size, &pgoff);
> -	if (rc)
> -		return rc;
>  	id = dax_read_lock();
>  	length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
>  				   NULL, pfnp);
> @@ -1129,7 +1124,7 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
>  s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
>  {
>  	sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
> -	pgoff_t pgoff;
> +	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>  	long rc, id;
>  	void *kaddr;
>  	bool page_aligned = false;
> @@ -1140,10 +1135,6 @@ s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
>  	    (size == PAGE_SIZE))
>  		page_aligned = true;
>  
> -	rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
> -	if (rc)
> -		return rc;
> -
>  	id = dax_read_lock();
>  
>  	if (page_aligned)
> @@ -1169,7 +1160,6 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>  	const struct iomap *iomap = &iomi->iomap;
>  	loff_t length = iomap_length(iomi);
>  	loff_t pos = iomi->pos;
> -	struct block_device *bdev = iomap->bdev;
>  	struct dax_device *dax_dev = iomap->dax_dev;
>  	loff_t end = pos + length, done = 0;
>  	ssize_t ret = 0;
> @@ -1203,9 +1193,8 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>  	while (pos < end) {
>  		unsigned offset = pos & (PAGE_SIZE - 1);
>  		const size_t size = ALIGN(length + offset, PAGE_SIZE);
> -		const sector_t sector = dax_iomap_sector(iomap, pos);
> +		pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
>  		ssize_t map_len;
> -		pgoff_t pgoff;
>  		void *kaddr;
>  
>  		if (fatal_signal_pending(current)) {
> @@ -1213,10 +1202,6 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
>  			break;
>  		}
>  
> -		ret = bdev_dax_pgoff(bdev, sector, size, &pgoff);
> -		if (ret)
> -			break;
> -
>  		map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
>  				&kaddr, NULL);
>  		if (map_len < 0) {
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 439c3c70e347b..324363b798ecd 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -107,7 +107,6 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
>  #endif
>  
>  struct writeback_control;
> -int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
>  #if IS_ENABLED(CONFIG_FS_DAX)
>  int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
>  void dax_remove_host(struct gendisk *disk);
> -- 
> 2.30.2
>
Christoph Hellwig Nov. 24, 2021, 6:39 a.m. UTC | #3
On Tue, Nov 23, 2021 at 02:36:42PM -0800, Darrick J. Wong wrote:
> > -	phys_addr_t phys_off = (start_sect + sector) * 512;
> > -
> > -	if (pgoff)
> > -		*pgoff = PHYS_PFN(phys_off);
> > -	if (phys_off % PAGE_SIZE || size % PAGE_SIZE)
> 
> AFAICT, we're relying on fs_dax_get_by_bdev to have validated this
> previously, which is why the error return stuff goes away?

Exactly.
diff mbox series

Patch

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 803942586d1b6..c0910687fbcb2 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -67,20 +67,6 @@  void dax_remove_host(struct gendisk *disk)
 }
 EXPORT_SYMBOL_GPL(dax_remove_host);
 
-int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
-		pgoff_t *pgoff)
-{
-	sector_t start_sect = bdev ? get_start_sect(bdev) : 0;
-	phys_addr_t phys_off = (start_sect + sector) * 512;
-
-	if (pgoff)
-		*pgoff = PHYS_PFN(phys_off);
-	if (phys_off % PAGE_SIZE || size % PAGE_SIZE)
-		return -EINVAL;
-	return 0;
-}
-EXPORT_SYMBOL(bdev_dax_pgoff);
-
 /**
  * dax_get_by_host() - temporary lookup mechanism for filesystem-dax
  * @bdev: block device to find a dax_device for
diff --git a/fs/dax.c b/fs/dax.c
index e51b4129d1b65..5364549d67a48 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -709,23 +709,22 @@  int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
 	return __dax_invalidate_entry(mapping, index, false);
 }
 
-static sector_t dax_iomap_sector(const struct iomap *iomap, loff_t pos)
+static pgoff_t dax_iomap_pgoff(const struct iomap *iomap, loff_t pos)
 {
-	return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
+	phys_addr_t paddr = iomap->addr + (pos & PAGE_MASK) - iomap->offset;
+
+	if (iomap->bdev)
+		paddr += (get_start_sect(iomap->bdev) << SECTOR_SHIFT);
+	return PHYS_PFN(paddr);
 }
 
 static int copy_cow_page_dax(struct vm_fault *vmf, const struct iomap_iter *iter)
 {
-	sector_t sector = dax_iomap_sector(&iter->iomap, iter->pos);
+	pgoff_t pgoff = dax_iomap_pgoff(&iter->iomap, iter->pos);
 	void *vto, *kaddr;
-	pgoff_t pgoff;
 	long rc;
 	int id;
 
-	rc = bdev_dax_pgoff(iter->iomap.bdev, sector, PAGE_SIZE, &pgoff);
-	if (rc)
-		return rc;
-
 	id = dax_read_lock();
 	rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, &kaddr, NULL);
 	if (rc < 0) {
@@ -1013,14 +1012,10 @@  EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
 static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,
 			 pfn_t *pfnp)
 {
-	const sector_t sector = dax_iomap_sector(iomap, pos);
-	pgoff_t pgoff;
+	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
 	int id, rc;
 	long length;
 
-	rc = bdev_dax_pgoff(iomap->bdev, sector, size, &pgoff);
-	if (rc)
-		return rc;
 	id = dax_read_lock();
 	length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
 				   NULL, pfnp);
@@ -1129,7 +1124,7 @@  static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
 {
 	sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
-	pgoff_t pgoff;
+	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
 	long rc, id;
 	void *kaddr;
 	bool page_aligned = false;
@@ -1140,10 +1135,6 @@  s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
 	    (size == PAGE_SIZE))
 		page_aligned = true;
 
-	rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
-	if (rc)
-		return rc;
-
 	id = dax_read_lock();
 
 	if (page_aligned)
@@ -1169,7 +1160,6 @@  static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
 	const struct iomap *iomap = &iomi->iomap;
 	loff_t length = iomap_length(iomi);
 	loff_t pos = iomi->pos;
-	struct block_device *bdev = iomap->bdev;
 	struct dax_device *dax_dev = iomap->dax_dev;
 	loff_t end = pos + length, done = 0;
 	ssize_t ret = 0;
@@ -1203,9 +1193,8 @@  static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
 	while (pos < end) {
 		unsigned offset = pos & (PAGE_SIZE - 1);
 		const size_t size = ALIGN(length + offset, PAGE_SIZE);
-		const sector_t sector = dax_iomap_sector(iomap, pos);
+		pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);
 		ssize_t map_len;
-		pgoff_t pgoff;
 		void *kaddr;
 
 		if (fatal_signal_pending(current)) {
@@ -1213,10 +1202,6 @@  static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
 			break;
 		}
 
-		ret = bdev_dax_pgoff(bdev, sector, size, &pgoff);
-		if (ret)
-			break;
-
 		map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
 				&kaddr, NULL);
 		if (map_len < 0) {
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 439c3c70e347b..324363b798ecd 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -107,7 +107,6 @@  static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
 #endif
 
 struct writeback_control;
-int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
 #if IS_ENABLED(CONFIG_FS_DAX)
 int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
 void dax_remove_host(struct gendisk *disk);