Chen Yang
2012-Nov-29 03:11 UTC
[PATCH] Btrfs: send - sparse file support for btrfs-send mechanism
when send/receive a sparse file, the holes of the original file
will be filled with zero. The holes will be sent as ZERO streams,
and it''s unnecessary.
So, I improved this by skipping the hole of file while sending.
Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com>
---
fs/btrfs/send.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index e78b297..1e1d59a 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -3718,6 +3718,7 @@ static int send_write_or_clone(struct send_ctx *sctx,
u64 pos = 0;
u64 len;
u32 l;
+ u64 bytenr;
u8 type;
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
@@ -3732,6 +3733,11 @@ static int send_write_or_clone(struct send_ctx *sctx,
*/
len = PAGE_CACHE_ALIGN(len);
} else {
+ bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], ei);
+ if (bytenr == 0) {
+ ret = 0;
+ goto out;
+ }
len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
}
--
1.7.7.6
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Chen Yang
2012-Nov-29 06:06 UTC
[PATCH] Btrfs: send - pre-allocated file support for btrfs-send mechanism
From 4222aa3a32cf4db161fcbbb87ad29b714f1bfaf2 Mon Sep 17 00:00:00 2001
From: Chen Yang <chenyang.fnst@cn.fujitsu.com>
Date: Thu, 29 Nov 2012 13:22:09 +0800
Subject: [PATCH] Btrfs: send - pre-allocated file support for btrfs-send
mechanism
when send or receive a file which has pre-allocated part,
the pre-allocated parts of the file will be sent as ZERO streams,
and it''s unnecessary.
So we can improve this by skip these EMPTY parts.
Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com>
---
this patch is based on
"Btrfs: send - sparse file support for btrfs-send mechanism"
---
fs/btrfs/send.c | 7 ++++++-
1 files changed, 6 insertions(+), 1 deletions(-)
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 1e1d59a..2d23184 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -3732,13 +3732,18 @@ static int send_write_or_clone(struct send_ctx *sctx,
* sure to send the whole thing
*/
len = PAGE_CACHE_ALIGN(len);
- } else {
+ } else if (type == BTRFS_FILE_EXTENT_REG) {
bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], ei);
if (bytenr == 0) {
ret = 0;
goto out;
}
len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
+ } else if (type == BTRFS_FILE_EXTENT_PREALLOC) {
+ ret = 0;
+ goto out;
+ } else {
+ BUG();
}
if (offset + len > sctx->cur_inode_size)
--
1.7.7.6
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Alexander Block
2012-Nov-29 08:54 UTC
Re: [PATCH] Btrfs: send - sparse file support for btrfs-send mechanism
On Thu, Nov 29, 2012 at 4:11 AM, Chen Yang <chenyang.fnst@cn.fujitsu.com> wrote:> when send/receive a sparse file, the holes of the original file > will be filled with zero. The holes will be sent as ZERO streams, > and it''s unnecessary. > > So, I improved this by skipping the hole of file while sending. > > Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com> > --- > fs/btrfs/send.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c > index e78b297..1e1d59a 100644 > --- a/fs/btrfs/send.c > +++ b/fs/btrfs/send.c > @@ -3718,6 +3718,7 @@ static int send_write_or_clone(struct send_ctx *sctx, > u64 pos = 0; > u64 len; > u32 l; > + u64 bytenr; > u8 type; > > ei = btrfs_item_ptr(path->nodes[0], path->slots[0], > @@ -3732,6 +3733,11 @@ static int send_write_or_clone(struct send_ctx *sctx, > */ > len = PAGE_CACHE_ALIGN(len); > } else { > + bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], ei); > + if (bytenr == 0) { > + ret = 0; > + goto out; > + } > len = btrfs_file_extent_num_bytes(path->nodes[0], ei); > } > > -- > 1.7.7.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.htmlThis won''t work for incremental sends if I understand it correctly. If the hole got punched into the file after the initial send, the data will be unchanged on the receiving side when receiving incrementally. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alexander Block
2012-Nov-29 08:55 UTC
Re: [PATCH] Btrfs: send - pre-allocated file support for btrfs-send mechanism
On Thu, Nov 29, 2012 at 7:06 AM, Chen Yang <chenyang.fnst@cn.fujitsu.com> wrote:> From 4222aa3a32cf4db161fcbbb87ad29b714f1bfaf2 Mon Sep 17 00:00:00 2001 > From: Chen Yang <chenyang.fnst@cn.fujitsu.com> > Date: Thu, 29 Nov 2012 13:22:09 +0800 > Subject: [PATCH] Btrfs: send - pre-allocated file support for btrfs-send > mechanism > > when send or receive a file which has pre-allocated part, > the pre-allocated parts of the file will be sent as ZERO streams, > and it''s unnecessary. > > So we can improve this by skip these EMPTY parts. > > Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com> > --- > this patch is based on > "Btrfs: send - sparse file support for btrfs-send mechanism" > --- > fs/btrfs/send.c | 7 ++++++- > 1 files changed, 6 insertions(+), 1 deletions(-) > > diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c > index 1e1d59a..2d23184 100644 > --- a/fs/btrfs/send.c > +++ b/fs/btrfs/send.c > @@ -3732,13 +3732,18 @@ static int send_write_or_clone(struct send_ctx *sctx, > * sure to send the whole thing > */ > len = PAGE_CACHE_ALIGN(len); > - } else { > + } else if (type == BTRFS_FILE_EXTENT_REG) { > bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], ei); > if (bytenr == 0) { > ret = 0; > goto out; > } > len = btrfs_file_extent_num_bytes(path->nodes[0], ei); > + } else if (type == BTRFS_FILE_EXTENT_PREALLOC) { > + ret = 0; > + goto out; > + } else { > + BUG(); > } > > if (offset + len > sctx->cur_inode_size) > -- > 1.7.7.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.htmlThe same as in my previous mail applies here. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alex Lyakas
2012-Dec-01 18:39 UTC
Re: [PATCH] Btrfs: send - pre-allocated file support for btrfs-send mechanism
Hi, and also, I think, for PREALLOC extents, it is not enough just to skip sending the data, but possibly need to perform preallocation on the receive side, so a new SEND command might be needed. Alex. On Thu, Nov 29, 2012 at 10:55 AM, Alexander Block <ablock84@gmail.com> wrote:> On Thu, Nov 29, 2012 at 7:06 AM, Chen Yang <chenyang.fnst@cn.fujitsu.com> wrote: >> From 4222aa3a32cf4db161fcbbb87ad29b714f1bfaf2 Mon Sep 17 00:00:00 2001 >> From: Chen Yang <chenyang.fnst@cn.fujitsu.com> >> Date: Thu, 29 Nov 2012 13:22:09 +0800 >> Subject: [PATCH] Btrfs: send - pre-allocated file support for btrfs-send >> mechanism >> >> when send or receive a file which has pre-allocated part, >> the pre-allocated parts of the file will be sent as ZERO streams, >> and it''s unnecessary. >> >> So we can improve this by skip these EMPTY parts. >> >> Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com> >> --- >> this patch is based on >> "Btrfs: send - sparse file support for btrfs-send mechanism" >> --- >> fs/btrfs/send.c | 7 ++++++- >> 1 files changed, 6 insertions(+), 1 deletions(-) >> >> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c >> index 1e1d59a..2d23184 100644 >> --- a/fs/btrfs/send.c >> +++ b/fs/btrfs/send.c >> @@ -3732,13 +3732,18 @@ static int send_write_or_clone(struct send_ctx *sctx, >> * sure to send the whole thing >> */ >> len = PAGE_CACHE_ALIGN(len); >> - } else { >> + } else if (type == BTRFS_FILE_EXTENT_REG) { >> bytenr = btrfs_file_extent_disk_bytenr(path->nodes[0], ei); >> if (bytenr == 0) { >> ret = 0; >> goto out; >> } >> len = btrfs_file_extent_num_bytes(path->nodes[0], ei); >> + } else if (type == BTRFS_FILE_EXTENT_PREALLOC) { >> + ret = 0; >> + goto out; >> + } else { >> + BUG(); >> } >> >> if (offset + len > sctx->cur_inode_size) >> -- >> 1.7.7.6 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > The same as in my previous mail applies here. > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alex Lyakas
2013-Jan-08 16:06 UTC
Re: [PATCH] Btrfs: send - sparse file support for btrfs-send mechanism
Hi Chen, Alexander, Jan,
how about the following patch: it works for disknr==0 extents (to
handle PREALLOC extents correctly, we need to add a new command, which
will break existing btrfs-progs, because they are updated slower than
the kernel side).
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 5445454..2b46d92 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -3946,16 +3946,38 @@ static int process_extent(struct send_ctx *sctx,
if (sctx->parent_root && !sctx->cur_inode_new) {
ret = is_extent_unchanged(sctx, path, key);
if (ret < 0)
goto out;
if (ret) {
ret = 0;
goto out;
}
+ } else {
+ struct extent_buffer *eb;
+ struct btrfs_file_extent_item *ei;
+ u8 extent_type;
+ u64 extent_disknr;
+
+ eb = path->nodes[0];
+ ei = btrfs_item_ptr(eb, path->slots[0],
+ struct btrfs_file_extent_item);
+
+ extent_type = btrfs_file_extent_type(eb, ei);
+ extent_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
+ if (extent_type == BTRFS_FILE_EXTENT_REG &&
extent_disknr == 0) {
+ /*
+ * This is disknr=0 extent in a full-send or a new inode
+ * in a diff-send. Since we will send truncate command
+ * in finish_inode_if_needed anyways, the
inode size will be
+ * correct, and we don''t have to send all-zero
data.
+ */
+ ret = 0;
+ goto out;
+ }
}
ret = find_extent_clone(sctx, path, key->objectid, key->offset,
sctx->cur_inode_size, &found_clone);
if (ret != -ENOENT && ret < 0)
goto out;
ret = send_write_or_clone(sctx, path, key, found_clone);
Thanks,
Alex.
On Thu, Nov 29, 2012 at 10:54 AM, Alexander Block <ablock84@gmail.com>
wrote:> On Thu, Nov 29, 2012 at 4:11 AM, Chen Yang
<chenyang.fnst@cn.fujitsu.com> wrote:
>> when send/receive a sparse file, the holes of the original file
>> will be filled with zero. The holes will be sent as ZERO streams,
>> and it''s unnecessary.
>>
>> So, I improved this by skipping the hole of file while sending.
>>
>> Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com>
>> ---
>> fs/btrfs/send.c | 6 ++++++
>> 1 files changed, 6 insertions(+), 0 deletions(-)
>>
>> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
>> index e78b297..1e1d59a 100644
>> --- a/fs/btrfs/send.c
>> +++ b/fs/btrfs/send.c
>> @@ -3718,6 +3718,7 @@ static int send_write_or_clone(struct send_ctx
*sctx,
>> u64 pos = 0;
>> u64 len;
>> u32 l;
>> + u64 bytenr;
>> u8 type;
>>
>> ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
>> @@ -3732,6 +3733,11 @@ static int send_write_or_clone(struct send_ctx
*sctx,
>> */
>> len = PAGE_CACHE_ALIGN(len);
>> } else {
>> + bytenr =
btrfs_file_extent_disk_bytenr(path->nodes[0], ei);
>> + if (bytenr == 0) {
>> + ret = 0;
>> + goto out;
>> + }
>> len = btrfs_file_extent_num_bytes(path->nodes[0],
ei);
>> }
>>
>> --
>> 1.7.7.6
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe
linux-btrfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
> This won''t work for incremental sends if I understand it
correctly. If
> the hole got punched into the file after the initial send, the data
> will be unchanged on the receiving side when receiving incrementally.
> --
> To unsubscribe from this list: send the line "unsubscribe
linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
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Alex Lyakas
2013-Jan-08 20:11 UTC
Re: [PATCH] Btrfs: send - sparse file support for btrfs-send mechanism
Hi,
I believe there are two more cases, where we can safely avoid shipping
disknr=0 extent. These are cases, in which the file grows between the
two snapshots, and some of the new extents are no-data extents. So the
whole patch becomes:
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 5445454..0bd96fe 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -3839,17 +3839,18 @@ static int is_extent_unchanged(struct send_ctx *sctx,
/*
* Handle special case where the right side has no extents at all.
*/
eb = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(eb, &found_key, slot);
if (found_key.objectid != key.objectid ||
found_key.type != key.type) {
- ret = 0;
+ /* No need to send a no-data extent it in this case */
+ ret = (left_disknr == 0) ? 1 : 0;
goto out;
}
/*
* We''re now on 2a, 2b or 7.
*/
key = found_key;
while (key.offset < ekey->offset + left_len) {
@@ -3865,17 +3866,18 @@ static int is_extent_unchanged(struct send_ctx *sctx,
goto out;
}
/*
* Are we at extent 8? If yes, we know the extent is changed.
* This may only happen on the first iteration.
*/
if (found_key.offset + right_len <= ekey->offset) {
- ret = 0;
+ /* No need to send a no-data extent it in this case */
+ ret = (left_disknr == 0) ? 1 : 0;
goto out;
}
left_offset_fixed = left_offset;
if (key.offset < ekey->offset) {
/* Fix the right offset for 2a and 7. */
right_offset += ekey->offset - key.offset;
} else {
@@ -3946,16 +3948,38 @@ static int process_extent(struct send_ctx *sctx,
if (sctx->parent_root && !sctx->cur_inode_new) {
ret = is_extent_unchanged(sctx, path, key);
if (ret < 0)
goto out;
if (ret) {
ret = 0;
goto out;
}
+ } else {
+ struct extent_buffer *eb;
+ struct btrfs_file_extent_item *ei;
+ u8 extent_type;
+ u64 extent_disknr;
+
+ eb = path->nodes[0];
+ ei = btrfs_item_ptr(eb, path->slots[0],
+ struct btrfs_file_extent_item);
+
+ extent_type = btrfs_file_extent_type(eb, ei);
+ extent_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
+ if (extent_type == BTRFS_FILE_EXTENT_REG && extent_disknr == 0) {
+ /*
+ * This is disknr=0 extent in a full-send or a new inode
+ * in a diff-send. Since we will send truncate command
+ * in finish_inode_if_needed anyways, the inode size will be
+ * correct, and we don''t have to send all-zero data.
+ */
+ ret = 0;
+ goto out;
+ }
}
ret = find_extent_clone(sctx, path, key->objectid, key->offset,
sctx->cur_inode_size, &found_clone);
if (ret != -ENOENT && ret < 0)
goto out;
ret = send_write_or_clone(sctx, path, key, found_clone);
Alex.
On Tue, Jan 8, 2013 at 6:06 PM, Alex Lyakas <alex@zadarastorage.com>
wrote:> Hi Chen, Alexander, Jan,
> how about the following patch: it works for disknr==0 extents (to
> handle PREALLOC extents correctly, we need to add a new command, which
> will break existing btrfs-progs, because they are updated slower than
> the kernel side).
>
> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
> index 5445454..2b46d92 100644
> --- a/fs/btrfs/send.c
> +++ b/fs/btrfs/send.c
> @@ -3946,16 +3946,38 @@ static int process_extent(struct send_ctx *sctx,
> if (sctx->parent_root && !sctx->cur_inode_new) {
> ret = is_extent_unchanged(sctx, path, key);
> if (ret < 0)
> goto out;
> if (ret) {
> ret = 0;
> goto out;
> }
> + } else {
> + struct extent_buffer *eb;
> + struct btrfs_file_extent_item *ei;
> + u8 extent_type;
> + u64 extent_disknr;
> +
> + eb = path->nodes[0];
> + ei = btrfs_item_ptr(eb, path->slots[0],
> + struct btrfs_file_extent_item);
> +
> + extent_type = btrfs_file_extent_type(eb, ei);
> + extent_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
> + if (extent_type == BTRFS_FILE_EXTENT_REG &&
> extent_disknr == 0) {
> + /*
> + * This is disknr=0 extent in a full-send or a new
inode
> + * in a diff-send. Since we will send truncate
command
> + * in finish_inode_if_needed anyways, the
> inode size will be
> + * correct, and we don''t have to send
all-zero data.
> + */
> + ret = 0;
> + goto out;
> + }
> }
>
> ret = find_extent_clone(sctx, path, key->objectid,
key->offset,
> sctx->cur_inode_size, &found_clone);
> if (ret != -ENOENT && ret < 0)
> goto out;
>
> ret = send_write_or_clone(sctx, path, key, found_clone);
>
> Thanks,
> Alex.
>
>
> On Thu, Nov 29, 2012 at 10:54 AM, Alexander Block
<ablock84@gmail.com> wrote:
>> On Thu, Nov 29, 2012 at 4:11 AM, Chen Yang
<chenyang.fnst@cn.fujitsu.com> wrote:
>>> when send/receive a sparse file, the holes of the original file
>>> will be filled with zero. The holes will be sent as ZERO streams,
>>> and it''s unnecessary.
>>>
>>> So, I improved this by skipping the hole of file while sending.
>>>
>>> Signed-off-by: Cheng Yang <chenyang.fnst@cn.fujitsu.com>
>>> ---
>>> fs/btrfs/send.c | 6 ++++++
>>> 1 files changed, 6 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
>>> index e78b297..1e1d59a 100644
>>> --- a/fs/btrfs/send.c
>>> +++ b/fs/btrfs/send.c
>>> @@ -3718,6 +3718,7 @@ static int send_write_or_clone(struct
send_ctx *sctx,
>>> u64 pos = 0;
>>> u64 len;
>>> u32 l;
>>> + u64 bytenr;
>>> u8 type;
>>>
>>> ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
>>> @@ -3732,6 +3733,11 @@ static int send_write_or_clone(struct
send_ctx *sctx,
>>> */
>>> len = PAGE_CACHE_ALIGN(len);
>>> } else {
>>> + bytenr =
btrfs_file_extent_disk_bytenr(path->nodes[0], ei);
>>> + if (bytenr == 0) {
>>> + ret = 0;
>>> + goto out;
>>> + }
>>> len =
btrfs_file_extent_num_bytes(path->nodes[0], ei);
>>> }
>>>
>>> --
>>> 1.7.7.6
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe
linux-btrfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>> This won''t work for incremental sends if I understand it
correctly. If
>> the hole got punched into the file after the initial send, the data
>> will be unchanged on the receiving side when receiving incrementally.
>> --
>> To unsubscribe from this list: send the line "unsubscribe
linux-btrfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
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