[sheepdog] [PATCH 1/2] sheep : add new strage type "tree"

[Liu Yuan]

On Thu, Mar 12, 2015 at 01:50:26PM +0900, Saeki Masaki wrote:
> Current sheepdog stores whole objects in single directory like "/var/lib/sheepdog/obj"
> This mechanism is difficult to handle massive files when increasing cluster volume.
> 
> In particular, inode object having special informations about VDI,
> so it is preferable to divide.
> 
> new storage type named "tree"
> It separates the inode object and data object.
> 
> How to use ,
> specify the --store option at the time format
> 
> dog cluster format --store tree
> 
> Signed-off-by: Masaki Saeki <saeki.masaki at po.ntts.co.jp>
> ---
>  sheep/Makefile.am  |    2 +-
>  sheep/md.c         |   14 +
>  sheep/sheep_priv.h |   13 +
>  sheep/tree_store.c |  844 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 872 insertions(+), 1 deletions(-)
>  create mode 100644 sheep/tree_store.c
> 
> diff --git a/sheep/Makefile.am b/sheep/Makefile.am
> index 7a08838..c6b7441 100644
> --- a/sheep/Makefile.am
> +++ b/sheep/Makefile.am
> @@ -27,7 +27,7 @@ sbin_PROGRAMS		= sheep
>  sheep_SOURCES		= sheep.c group.c request.c gateway.c store.c vdi.c \
>  			  journal.c ops.c recovery.c cluster/local.c \
>  			  object_cache.c object_list_cache.c \
> -			  plain_store.c config.c migrate.c md.c
> +			  plain_store.c tree_store.c config.c migrate.c md.c
>  
>  if BUILD_HTTP
>  sheep_SOURCES		+= http/http.c http/kv.c http/s3.c http/swift.c \
> diff --git a/sheep/md.c b/sheep/md.c
> index c00d7a5..7aca7c0 100644
> --- a/sheep/md.c
> +++ b/sheep/md.c
> @@ -212,6 +212,20 @@ static int for_each_object_in_path(const char *path,
>  		if (unlikely(!strncmp(d->d_name, ".", 1)))
>  			continue;
>  
> +		/* recursive call for tree store driver sub directories*/
> +		if (check_store_name("tree")) {
> +			struct stat s;
> +
> +			snprintf(file_name, sizeof(file_name),
> +				 "%s/%s", path, d->d_name);
> +			stat(file_name, &s);
> +			if (S_ISDIR(s.st_mode)) {
> +				ret = for_each_object_in_path(file_name,
> +						func, cleanup, vinfo, arg);
> +				continue;
> +			}
> +		}
> +
>  		sd_debug("%s, %s", path, d->d_name);
>  		oid = strtoull(d->d_name, NULL, 16);
>  		if (oid == 0 || oid == ULLONG_MAX)
> diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
> index 26afa89..3c3154d 100644
> --- a/sheep/sheep_priv.h
> +++ b/sheep/sheep_priv.h
> @@ -269,6 +269,18 @@ int default_format(void);
>  int default_remove_object(uint64_t oid, uint8_t ec_index);
>  int default_get_hash(uint64_t oid, uint32_t epoch, uint8_t *sha1);
>  int default_purge_obj(void);
> +int tree_init(void);
> +bool tree_exist(uint64_t oid, uint8_t ec_index);
> +int tree_create_and_write(uint64_t oid, const struct siocb *iocb);
> +int tree_write(uint64_t oid, const struct siocb *iocb);
> +int tree_read(uint64_t oid, const struct siocb *iocb);
> +int tree_link(uint64_t oid, uint32_t tgt_epoch);
> +int tree_update_epoch(uint32_t epoch);
> +int tree_cleanup(void);
> +int tree_format(void);
> +int tree_remove_object(uint64_t oid, uint8_t ec_index);
> +int tree_get_hash(uint64_t oid, uint32_t epoch, uint8_t *sha1);
> +int tree_purge_obj(void);
>  int for_each_object_in_wd(int (*func)(uint64_t, const char *, uint32_t,
>  				      uint8_t, struct vnode_info *, void *),
>  			  bool, void *);
> @@ -278,6 +290,7 @@ int for_each_object_in_stale(int (*func)(uint64_t oid, const char *path,
>  			     void *arg);
>  int for_each_obj_path(int (*func)(const char *path));
>  size_t get_store_objsize(uint64_t oid);
> +bool check_store_name(const char *name);
>  
>  extern struct list_head store_drivers;
>  #define add_store_driver(driver)				\
> diff --git a/sheep/tree_store.c b/sheep/tree_store.c
> new file mode 100644
> index 0000000..7402f42
> --- /dev/null
> +++ b/sheep/tree_store.c
> @@ -0,0 +1,844 @@
> +/*
> + * Copyright (C) 2012 Nippon Telegraph and Telephone Corporation.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License version
> + * 2 as published by the Free Software Foundation.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <libgen.h>
> +#include <linux/falloc.h>
> +
> +#include "sheep_priv.h"
> +
> +#ifndef FALLOC_FL_PUNCH_HOLE
> +#define FALLOC_FL_PUNCH_HOLE 0x02
> +#endif
> +
> +#define sector_algined(x) ({ ((x) & (SECTOR_SIZE - 1)) == 0; })
> +
> +static inline bool iocb_is_aligned(const struct siocb *iocb)
> +{
> +	return  sector_algined(iocb->offset) && sector_algined(iocb->length);
> +}
> +
> +static int prepare_iocb(uint64_t oid, const struct siocb *iocb, bool create)
> +{
> +	int syncflag = create ? O_SYNC : O_DSYNC;
> +	int flags = syncflag | O_RDWR;
> +
> +	if (uatomic_is_true(&sys->use_journal) || sys->nosync == true)
> +		flags &= ~syncflag;
> +
> +	if (sys->backend_dio && iocb_is_aligned(iocb)) {
> +		if (!is_aligned_to_pagesize(iocb->buf))
> +			panic("Memory isn't aligned to pagesize %p", iocb->buf);
> +		flags |= O_DIRECT;
> +	}
> +
> +	if (create)
> +		flags |= O_CREAT | O_EXCL;
> +
> +	return flags;
> +}

I think you need preparation patch to share these duplicated lines.

Thanks,
Yuan