RE: [PATCH v3 08/10] fsdax: Dedup file range to use a compare function
> -Original Message-
> From: Ritesh Harjani
> Subject: Re: [PATCH v3 08/10] fsdax: Dedup file range to use a compare
> function
>
> On 21/03/19 09:52AM, Shiyang Ruan wrote:
> > With dax we cannot deal with readpage() etc. So, we create a dax
> > comparison funciton which is similar with
> > vfs_dedupe_file_range_compare().
> > And introduce dax_remap_file_range_prep() for filesystem use.
> >
> > Signed-off-by: Goldwyn Rodrigues
> > Signed-off-by: Shiyang Ruan
> > ---
> > fs/dax.c | 56
>
> > fs/remap_range.c | 45 ---
> > fs/xfs/xfs_reflink.c | 9 +--
> > include/linux/dax.h | 4
> > include/linux/fs.h | 15
> > 5 files changed, 115 insertions(+), 14 deletions(-)
> >
> > diff --git a/fs/dax.c b/fs/dax.c
> > index 348297b38f76..76f81f1d76ec 100644
> > --- a/fs/dax.c
> > +++ b/fs/dax.c
> > @@ -1833,3 +1833,59 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault
> *vmf,
> > return dax_insert_pfn_mkwrite(vmf, pfn, order); }
> > EXPORT_SYMBOL_GPL(dax_finish_sync_fault);
> > +
> > +static loff_t dax_range_compare_actor(struct inode *ino1, loff_t pos1,
> > + struct inode *ino2, loff_t pos2, loff_t len, void *data,
> > + struct iomap *smap, struct iomap *dmap) {
> > + void *saddr, *daddr;
> > + bool *same = data;
> > + int ret;
> > +
> > + if (smap->type == IOMAP_HOLE && dmap->type == IOMAP_HOLE) {
> > + *same = true;
> > + return len;
> > + }
> > +
> > + if (smap->type == IOMAP_HOLE || dmap->type == IOMAP_HOLE) {
> > + *same = false;
> > + return 0;
> > + }
> > +
> > + ret = dax_iomap_direct_access(smap, pos1, ALIGN(pos1 + len, PAGE_SIZE),
> > + , NULL);
>
> shouldn't it take len as the second argument?
The second argument of dax_iomap_direct_access() means offset, and the third
one means length. So, I think this is right.
>
> > + if (ret < 0)
> > + return -EIO;
> > +
> > + ret = dax_iomap_direct_access(dmap, pos2, ALIGN(pos2 + len, PAGE_SIZE),
> > + , NULL);
>
> ditto.
> > + if (ret < 0)
> > + return -EIO;
> > +
> > + *same = !memcmp(saddr, daddr, len);
> > + return len;
> > +}
> > +
> > +int dax_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> > + struct inode *dest, loff_t destoff, loff_t len, bool *is_same,
> > + const struct iomap_ops *ops)
> > +{
> > + int id, ret = 0;
> > +
> > + id = dax_read_lock();
> > + while (len) {
> > + ret = iomap_apply2(src, srcoff, dest, destoff, len, 0, ops,
> > + is_same, dax_range_compare_actor);
> > + if (ret < 0 || !*is_same)
> > + goto out;
> > +
> > + len -= ret;
> > + srcoff += ret;
> > + destoff += ret;
> > + }
> > + ret = 0;
> > +out:
> > + dax_read_unlock(id);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(dax_dedupe_file_range_compare);
> > diff --git a/fs/remap_range.c b/fs/remap_range.c index
> > 77dba3a49e65..9079390edaf3 100644
> > --- a/fs/remap_range.c
> > +++ b/fs/remap_range.c
> > @@ -14,6 +14,7 @@
> > #include
> > #include
> > #include
> > +#include
> > #include "internal.h"
> >
> > #include
> > @@ -199,9 +200,9 @@ static void vfs_unlock_two_pages(struct page *page1,
> struct page *page2)
> > * Compare extents of two files to see if they are the same.
> > * Caller must have locked both inodes to prevent write races.
> > */
> > -static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> > -struct inode *dest, loff_t destoff,
> > -loff_t len, bool *is_same)
> > +int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> > + struct inode *dest, loff_t destoff,
> > + loff_t len, bool *is_same)
> > {
> > loff_t src_poff;
> > loff_t dest_poff;
> > @@ -280,6 +281,7 @@ static int vfs_dedupe_file_range_compare(struct
> > inode *src, loff_t srcoff,
> > out_error:
> > return error;
> > }
> > +EXPORT_SYMBOL(vfs_dedup
Re: [PATCH v3 08/10] fsdax: Dedup file range to use a compare function
On 21/03/19 09:52AM, Shiyang Ruan wrote:
> With dax we cannot deal with readpage() etc. So, we create a dax
> comparison funciton which is similar with
> vfs_dedupe_file_range_compare().
> And introduce dax_remap_file_range_prep() for filesystem use.
>
> Signed-off-by: Goldwyn Rodrigues
> Signed-off-by: Shiyang Ruan
> ---
> fs/dax.c | 56
> fs/remap_range.c | 45 ---
> fs/xfs/xfs_reflink.c | 9 +--
> include/linux/dax.h | 4
> include/linux/fs.h | 15
> 5 files changed, 115 insertions(+), 14 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index 348297b38f76..76f81f1d76ec 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -1833,3 +1833,59 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
> return dax_insert_pfn_mkwrite(vmf, pfn, order);
> }
> EXPORT_SYMBOL_GPL(dax_finish_sync_fault);
> +
> +static loff_t dax_range_compare_actor(struct inode *ino1, loff_t pos1,
> + struct inode *ino2, loff_t pos2, loff_t len, void *data,
> + struct iomap *smap, struct iomap *dmap)
> +{
> + void *saddr, *daddr;
> + bool *same = data;
> + int ret;
> +
> + if (smap->type == IOMAP_HOLE && dmap->type == IOMAP_HOLE) {
> + *same = true;
> + return len;
> + }
> +
> + if (smap->type == IOMAP_HOLE || dmap->type == IOMAP_HOLE) {
> + *same = false;
> + return 0;
> + }
> +
> + ret = dax_iomap_direct_access(smap, pos1, ALIGN(pos1 + len, PAGE_SIZE),
> + , NULL);
shouldn't it take len as the second argument?
> + if (ret < 0)
> + return -EIO;
> +
> + ret = dax_iomap_direct_access(dmap, pos2, ALIGN(pos2 + len, PAGE_SIZE),
> + , NULL);
ditto.
> + if (ret < 0)
> + return -EIO;
> +
> + *same = !memcmp(saddr, daddr, len);
> + return len;
> +}
> +
> +int dax_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> + struct inode *dest, loff_t destoff, loff_t len, bool *is_same,
> + const struct iomap_ops *ops)
> +{
> + int id, ret = 0;
> +
> + id = dax_read_lock();
> + while (len) {
> + ret = iomap_apply2(src, srcoff, dest, destoff, len, 0, ops,
> +is_same, dax_range_compare_actor);
> + if (ret < 0 || !*is_same)
> + goto out;
> +
> + len -= ret;
> + srcoff += ret;
> + destoff += ret;
> + }
> + ret = 0;
> +out:
> + dax_read_unlock(id);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(dax_dedupe_file_range_compare);
> diff --git a/fs/remap_range.c b/fs/remap_range.c
> index 77dba3a49e65..9079390edaf3 100644
> --- a/fs/remap_range.c
> +++ b/fs/remap_range.c
> @@ -14,6 +14,7 @@
> #include
> #include
> #include
> +#include
> #include "internal.h"
>
> #include
> @@ -199,9 +200,9 @@ static void vfs_unlock_two_pages(struct page *page1,
> struct page *page2)
> * Compare extents of two files to see if they are the same.
> * Caller must have locked both inodes to prevent write races.
> */
> -static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> - struct inode *dest, loff_t destoff,
> - loff_t len, bool *is_same)
> +int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
> + struct inode *dest, loff_t destoff,
> + loff_t len, bool *is_same)
> {
> loff_t src_poff;
> loff_t dest_poff;
> @@ -280,6 +281,7 @@ static int vfs_dedupe_file_range_compare(struct inode
> *src, loff_t srcoff,
> out_error:
> return error;
> }
> +EXPORT_SYMBOL(vfs_dedupe_file_range_compare);
>
> /*
> * Check that the two inodes are eligible for cloning, the ranges make
> @@ -289,9 +291,11 @@ static int vfs_dedupe_file_range_compare(struct inode
> *src, loff_t srcoff,
> * If there's an error, then the usual negative error code is returned.
> * Otherwise returns 0 with *len set to the request length.
> */
> -int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
> - struct file *file_out, loff_t pos_out,
> - loff_t *len, unsigned int remap_flags)
> +static int
> +__generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
> + struct file *file_out, loff_t pos_out,
> + loff_t *len, unsigned int remap_flags,
> + const struct iomap_ops *ops)
> {
> struct inode *inode_in = file_inode(file_in);
> struct inode *inode_out = file_inode(file_out);
> @@ -351,8 +355,15 @@ int generic_remap_file_range_prep(struct file *file_in,
> loff_t pos_in,
> if (remap_flags & REMAP_FILE_DEDUP) {
>
[PATCH v3 08/10] fsdax: Dedup file range to use a compare function
With dax we cannot deal with readpage() etc. So, we create a dax
comparison funciton which is similar with
vfs_dedupe_file_range_compare().
And introduce dax_remap_file_range_prep() for filesystem use.
Signed-off-by: Goldwyn Rodrigues
Signed-off-by: Shiyang Ruan
---
fs/dax.c | 56
fs/remap_range.c | 45 ---
fs/xfs/xfs_reflink.c | 9 +--
include/linux/dax.h | 4
include/linux/fs.h | 15
5 files changed, 115 insertions(+), 14 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 348297b38f76..76f81f1d76ec 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1833,3 +1833,59 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
return dax_insert_pfn_mkwrite(vmf, pfn, order);
}
EXPORT_SYMBOL_GPL(dax_finish_sync_fault);
+
+static loff_t dax_range_compare_actor(struct inode *ino1, loff_t pos1,
+ struct inode *ino2, loff_t pos2, loff_t len, void *data,
+ struct iomap *smap, struct iomap *dmap)
+{
+ void *saddr, *daddr;
+ bool *same = data;
+ int ret;
+
+ if (smap->type == IOMAP_HOLE && dmap->type == IOMAP_HOLE) {
+ *same = true;
+ return len;
+ }
+
+ if (smap->type == IOMAP_HOLE || dmap->type == IOMAP_HOLE) {
+ *same = false;
+ return 0;
+ }
+
+ ret = dax_iomap_direct_access(smap, pos1, ALIGN(pos1 + len, PAGE_SIZE),
+ , NULL);
+ if (ret < 0)
+ return -EIO;
+
+ ret = dax_iomap_direct_access(dmap, pos2, ALIGN(pos2 + len, PAGE_SIZE),
+ , NULL);
+ if (ret < 0)
+ return -EIO;
+
+ *same = !memcmp(saddr, daddr, len);
+ return len;
+}
+
+int dax_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
+ struct inode *dest, loff_t destoff, loff_t len, bool *is_same,
+ const struct iomap_ops *ops)
+{
+ int id, ret = 0;
+
+ id = dax_read_lock();
+ while (len) {
+ ret = iomap_apply2(src, srcoff, dest, destoff, len, 0, ops,
+ is_same, dax_range_compare_actor);
+ if (ret < 0 || !*is_same)
+ goto out;
+
+ len -= ret;
+ srcoff += ret;
+ destoff += ret;
+ }
+ ret = 0;
+out:
+ dax_read_unlock(id);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dax_dedupe_file_range_compare);
diff --git a/fs/remap_range.c b/fs/remap_range.c
index 77dba3a49e65..9079390edaf3 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -14,6 +14,7 @@
#include
#include
#include
+#include
#include "internal.h"
#include
@@ -199,9 +200,9 @@ static void vfs_unlock_two_pages(struct page *page1, struct
page *page2)
* Compare extents of two files to see if they are the same.
* Caller must have locked both inodes to prevent write races.
*/
-static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
-struct inode *dest, loff_t destoff,
-loff_t len, bool *is_same)
+int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
+ struct inode *dest, loff_t destoff,
+ loff_t len, bool *is_same)
{
loff_t src_poff;
loff_t dest_poff;
@@ -280,6 +281,7 @@ static int vfs_dedupe_file_range_compare(struct inode *src,
loff_t srcoff,
out_error:
return error;
}
+EXPORT_SYMBOL(vfs_dedupe_file_range_compare);
/*
* Check that the two inodes are eligible for cloning, the ranges make
@@ -289,9 +291,11 @@ static int vfs_dedupe_file_range_compare(struct inode
*src, loff_t srcoff,
* If there's an error, then the usual negative error code is returned.
* Otherwise returns 0 with *len set to the request length.
*/
-int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out,
- loff_t *len, unsigned int remap_flags)
+static int
+__generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ loff_t *len, unsigned int remap_flags,
+ const struct iomap_ops *ops)
{
struct inode *inode_in = file_inode(file_in);
struct inode *inode_out = file_inode(file_out);
@@ -351,8 +355,15 @@ int generic_remap_file_range_prep(struct file *file_in,
loff_t pos_in,
if (remap_flags & REMAP_FILE_DEDUP) {
boolis_same = false;
- ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
- inode_out, pos_out, *len, _same);
+ if (!IS_DAX(inode_in) && !IS_DAX(inode_out))
+
