[PATCH 03/21] Btrfs: add BTRFS_AVAIL_ALLOC_BIT_SINGLE bit

2012-01-06 Thread Ilya Dryomov 
Right now on-disk BTRFS_BLOCK_GROUP_* profile bits are used for
avail_{data,metadata,system}_alloc_bits fields, which gather info about
available allocation profiles in the FS.  When chunk is created or read
from disk, its profile is OR'ed with the corresponding avail_alloc_bits
field.  Since SINGLE is denoted by 0 in the on-disk format, currently
there is no way to tell when such chunks become avaialble.  Restriper
needs that information, so add a separate bit for SINGLE profile.

This bit is going to be in-memory only, it should never be written out
to disk, so it's not a disk format change.  However to avoid remappings
in future, reserve corresponding on-disk bit.

Signed-off-by: Ilya Dryomov idryo...@gmail.com
---
 fs/btrfs/ctree.h   |   15 +++
 fs/btrfs/extent-tree.c |   30 +-
 2 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4370a56..3f8f11e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -758,6 +758,7 @@ struct btrfs_csum_item {
 #define BTRFS_BLOCK_GROUP_RAID1(1ULL  4)
 #define BTRFS_BLOCK_GROUP_DUP  (1ULL  5)
 #define BTRFS_BLOCK_GROUP_RAID10   (1ULL  6)
+#define BTRFS_BLOCK_GROUP_RESERVED BTRFS_AVAIL_ALLOC_BIT_SINGLE
 #define BTRFS_NR_RAID_TYPES5
 
 #define BTRFS_BLOCK_GROUP_TYPE_MASK(BTRFS_BLOCK_GROUP_DATA |\
@@ -768,6 +769,15 @@ struct btrfs_csum_item {
 BTRFS_BLOCK_GROUP_RAID1 |   \
 BTRFS_BLOCK_GROUP_DUP | \
 BTRFS_BLOCK_GROUP_RAID10)
+/*
+ * We need a bit for restriper to be able to tell when chunks of type
+ * SINGLE are available.  This extended profile format is used in
+ * fs_info-avail_*_alloc_bits (in-memory) and balance item fields
+ * (on-disk).  The corresponding on-disk bit in chunk.type is reserved
+ * to avoid remappings between two formats in future.
+ */
+#define BTRFS_AVAIL_ALLOC_BIT_SINGLE   (1ULL  48)
+
 struct btrfs_block_group_item {
__le64 used;
__le64 chunk_objectid;
@@ -1140,6 +1150,11 @@ struct btrfs_fs_info {
spinlock_t ref_cache_lock;
u64 total_ref_cache_size;
 
+   /*
+* these three are in extended format (availability of single
+* chunks is denoted by BTRFS_AVAIL_ALLOC_BIT_SINGLE bit, other
+* types are denoted by corresponding BTRFS_BLOCK_GROUP_* bits)
+*/
u64 avail_data_alloc_bits;
u64 avail_metadata_alloc_bits;
u64 avail_system_alloc_bits;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index a8d8204..15a2294 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3014,16 +3014,24 @@ static int update_space_info(struct btrfs_fs_info 
*info, u64 flags,
 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 {
u64 extra_flags = flags  BTRFS_BLOCK_GROUP_PROFILE_MASK;
-   if (extra_flags) {
-   if (flags  BTRFS_BLOCK_GROUP_DATA)
-   fs_info-avail_data_alloc_bits |= extra_flags;
-   if (flags  BTRFS_BLOCK_GROUP_METADATA)
-   fs_info-avail_metadata_alloc_bits |= extra_flags;
-   if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
-   fs_info-avail_system_alloc_bits |= extra_flags;
-   }
+
+   /* chunk - extended profile */
+   if (extra_flags == 0)
+   extra_flags = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
+
+   if (flags  BTRFS_BLOCK_GROUP_DATA)
+   fs_info-avail_data_alloc_bits |= extra_flags;
+   if (flags  BTRFS_BLOCK_GROUP_METADATA)
+   fs_info-avail_metadata_alloc_bits |= extra_flags;
+   if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
+   fs_info-avail_system_alloc_bits |= extra_flags;
 }
 
+/*
+ * @flags: available profiles in extended format (see ctree.h)
+ *
+ * Returns reduced profile in chunk format.
+ */
 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 {
/*
@@ -3053,8 +3061,12 @@ u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, 
u64 flags)
if ((flags  BTRFS_BLOCK_GROUP_RAID0) 
((flags  BTRFS_BLOCK_GROUP_RAID1) |
 (flags  BTRFS_BLOCK_GROUP_RAID10) |
-(flags  BTRFS_BLOCK_GROUP_DUP)))
+(flags  BTRFS_BLOCK_GROUP_DUP))) {
flags = ~BTRFS_BLOCK_GROUP_RAID0;
+   }
+
+   /* extended - chunk profile */
+   flags = ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
return flags;
 }
 
-- 
1.7.6.3

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Re: [PATCH 03/21] Btrfs: add BTRFS_AVAIL_ALLOC_BIT_SINGLE bit

2011-11-01 Thread Arne Jansen 
On 23.08.2011 22:01, Ilya Dryomov wrote:
 Right now on-disk BTRFS_BLOCK_GROUP_* profile bits are used for
 avail_{data,metadata,system}_alloc_bits fields, which are there to tell
 us about available allocation profiles in the fs.  When chunk is
 created, it's profile is OR'ed with respective avail_alloc_bits field.
 Since SINGLE is denoted by 0 in the on-disk format, currently there is
 no way to tell when such chunks become avaialble.  Restriper needs that
 information, so add a separate bit for SINGLE profile.
 
 This bit is going to be in-memory only, it should never be written out
 to disk, so it's not a disk format change.  However to avoid remappings
 in future, reserve corresponding on-disk bit.
 
 Signed-off-by: Ilya Dryomov idryo...@gmail.com
 ---
  fs/btrfs/ctree.h   |   12 
  fs/btrfs/extent-tree.c |   22 ++
  2 files changed, 26 insertions(+), 8 deletions(-)
 
 diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
 index b882c95..5b00eb8 100644
 --- a/fs/btrfs/ctree.h
 +++ b/fs/btrfs/ctree.h
 @@ -725,6 +725,17 @@ struct btrfs_csum_item {
BTRFS_BLOCK_GROUP_RAID1 |   \
BTRFS_BLOCK_GROUP_DUP | \
BTRFS_BLOCK_GROUP_RAID10)
 +/*
 + * We need a bit for restriper to be able to tell when chunks of type
 + * SINGLE are available.  It is used in avail_*_alloc_bits.
 + */
 +#define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1  7)
 +
 +/*
 + * To avoid troubles or remappings, reserve on-disk bit.
 + */
 +#define BTRFS_BLOCK_GROUP_RESERVED   (1  7)

can you move this define up to where the other BLOCK_GROUPS are defined?
Otherwise it is easy to overlook.

 +
  struct btrfs_block_group_item {
   __le64 used;
   __le64 chunk_objectid;
 @@ -1100,6 +,7 @@ struct btrfs_fs_info {
   spinlock_t ref_cache_lock;
   u64 total_ref_cache_size;
  
 + /* SINGLE has it's own bit for these three */

While this comment is easily understandable in the context in this patch,
it is not enough when just reading the resulting code without the commit
message. It would be good if you could duplicate more of the commit message
into code comments.

   u64 avail_data_alloc_bits;
   u64 avail_metadata_alloc_bits;
   u64 avail_system_alloc_bits;
 diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
 index de4c639..ed35eb5 100644
 --- a/fs/btrfs/extent-tree.c
 +++ b/fs/btrfs/extent-tree.c
 @@ -2945,14 +2945,17 @@ static int update_space_info(struct btrfs_fs_info 
 *info, u64 flags,
  static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
  {
   u64 extra_flags = flags  BTRFS_BLOCK_GROUP_PROFILE_MASK;
 - if (extra_flags) {
 - if (flags  BTRFS_BLOCK_GROUP_DATA)
 - fs_info-avail_data_alloc_bits |= extra_flags;
 - if (flags  BTRFS_BLOCK_GROUP_METADATA)
 - fs_info-avail_metadata_alloc_bits |= extra_flags;
 - if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
 - fs_info-avail_system_alloc_bits |= extra_flags;
 - }
 +
 + /* on-disk - in-memory */
 + if (extra_flags == 0)
 + extra_flags = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
 +
 + if (flags  BTRFS_BLOCK_GROUP_DATA)
 + fs_info-avail_data_alloc_bits |= extra_flags;
 + if (flags  BTRFS_BLOCK_GROUP_METADATA)
 + fs_info-avail_metadata_alloc_bits |= extra_flags;
 + if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
 + fs_info-avail_system_alloc_bits |= extra_flags;
  }
  
  u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 @@ -2986,6 +2989,9 @@ u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, 
 u64 flags)
(flags  BTRFS_BLOCK_GROUP_RAID10) |
(flags  BTRFS_BLOCK_GROUP_DUP)))
   flags = ~BTRFS_BLOCK_GROUP_RAID0;
 +
 + /* in-memory - on-disk */
 + flags = ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
   return flags;
  }
  

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[PATCH 03/21] Btrfs: add BTRFS_AVAIL_ALLOC_BIT_SINGLE bit

2011-08-23 Thread Ilya Dryomov 
Right now on-disk BTRFS_BLOCK_GROUP_* profile bits are used for
avail_{data,metadata,system}_alloc_bits fields, which are there to tell
us about available allocation profiles in the fs.  When chunk is
created, it's profile is OR'ed with respective avail_alloc_bits field.
Since SINGLE is denoted by 0 in the on-disk format, currently there is
no way to tell when such chunks become avaialble.  Restriper needs that
information, so add a separate bit for SINGLE profile.

This bit is going to be in-memory only, it should never be written out
to disk, so it's not a disk format change.  However to avoid remappings
in future, reserve corresponding on-disk bit.

Signed-off-by: Ilya Dryomov idryo...@gmail.com
---
 fs/btrfs/ctree.h   |   12 
 fs/btrfs/extent-tree.c |   22 ++
 2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b882c95..5b00eb8 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -725,6 +725,17 @@ struct btrfs_csum_item {
 BTRFS_BLOCK_GROUP_RAID1 |   \
 BTRFS_BLOCK_GROUP_DUP | \
 BTRFS_BLOCK_GROUP_RAID10)
+/*
+ * We need a bit for restriper to be able to tell when chunks of type
+ * SINGLE are available.  It is used in avail_*_alloc_bits.
+ */
+#define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1  7)
+
+/*
+ * To avoid troubles or remappings, reserve on-disk bit.
+ */
+#define BTRFS_BLOCK_GROUP_RESERVED   (1  7)
+
 struct btrfs_block_group_item {
__le64 used;
__le64 chunk_objectid;
@@ -1100,6 +,7 @@ struct btrfs_fs_info {
spinlock_t ref_cache_lock;
u64 total_ref_cache_size;
 
+   /* SINGLE has it's own bit for these three */
u64 avail_data_alloc_bits;
u64 avail_metadata_alloc_bits;
u64 avail_system_alloc_bits;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index de4c639..ed35eb5 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2945,14 +2945,17 @@ static int update_space_info(struct btrfs_fs_info 
*info, u64 flags,
 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 {
u64 extra_flags = flags  BTRFS_BLOCK_GROUP_PROFILE_MASK;
-   if (extra_flags) {
-   if (flags  BTRFS_BLOCK_GROUP_DATA)
-   fs_info-avail_data_alloc_bits |= extra_flags;
-   if (flags  BTRFS_BLOCK_GROUP_METADATA)
-   fs_info-avail_metadata_alloc_bits |= extra_flags;
-   if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
-   fs_info-avail_system_alloc_bits |= extra_flags;
-   }
+
+   /* on-disk - in-memory */
+   if (extra_flags == 0)
+   extra_flags = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
+
+   if (flags  BTRFS_BLOCK_GROUP_DATA)
+   fs_info-avail_data_alloc_bits |= extra_flags;
+   if (flags  BTRFS_BLOCK_GROUP_METADATA)
+   fs_info-avail_metadata_alloc_bits |= extra_flags;
+   if (flags  BTRFS_BLOCK_GROUP_SYSTEM)
+   fs_info-avail_system_alloc_bits |= extra_flags;
 }
 
 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
@@ -2986,6 +2989,9 @@ u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, 
u64 flags)
 (flags  BTRFS_BLOCK_GROUP_RAID10) |
 (flags  BTRFS_BLOCK_GROUP_DUP)))
flags = ~BTRFS_BLOCK_GROUP_RAID0;
+
+   /* in-memory - on-disk */
+   flags = ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
return flags;
 }
 
-- 
1.7.5.4

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