| Message ID | 1429712816-10336-3-git-send-email-m@bjorling.me (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 22, 2015 at 04:26:51PM +0200, Matias Bj??rling wrote: > In preparation for Open-Channel SSDs. We introduce a special request for > open-channel ssd targets that must perform garbage collection. > > Requests are divided into two types. The user and target specific. User > IOs are from fs, user-space, etc. While target specific are IOs that are > issued in the background by targets. Usually garbage collection actions. > > For the target to issue garbage collection requests, it is a requirement > that a logical address is locked over two requests. One read and one > write. If a write to the logical address comes in from user-space, a > race-condition might occur and garbage collection will write out-dated > data. > > By introducing this flag, the target can manually control locking of > logical addresses. Seems like this should be a new ->cmd_type instead of a flag. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 272c17e..25c6e02 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -195,6 +195,7 @@ enum rq_flag_bits { __REQ_HASHED, /* on IO scheduler merge hash */ __REQ_MQ_INFLIGHT, /* track inflight for MQ */ __REQ_NO_TIMEOUT, /* requests may never expire */ + __REQ_NVM_GC, /* request is a nvm gc request */ __REQ_NR_BITS, /* stops here */ }; @@ -215,7 +216,7 @@ enum rq_flag_bits { #define REQ_COMMON_MASK \ (REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | \ REQ_DISCARD | REQ_WRITE_SAME | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | \ - REQ_SECURE | REQ_INTEGRITY) + REQ_SECURE | REQ_INTEGRITY | REQ_NVM_GC) #define REQ_CLONE_MASK REQ_COMMON_MASK #define BIO_NO_ADVANCE_ITER_MASK (REQ_DISCARD|REQ_WRITE_SAME) @@ -249,5 +250,5 @@ enum rq_flag_bits { #define REQ_HASHED (1ULL << __REQ_HASHED) #define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT) #define REQ_NO_TIMEOUT (1ULL << __REQ_NO_TIMEOUT) - +#define REQ_NVM_GC (1ULL << __REQ_NVM_GC) #endif /* __LINUX_BLK_TYPES_H */
In preparation for Open-Channel SSDs. We introduce a special request for open-channel ssd targets that must perform garbage collection. Requests are divided into two types. The user and target specific. User IOs are from fs, user-space, etc. While target specific are IOs that are issued in the background by targets. Usually garbage collection actions. For the target to issue garbage collection requests, it is a requirement that a logical address is locked over two requests. One read and one write. If a write to the logical address comes in from user-space, a race-condition might occur and garbage collection will write out-dated data. By introducing this flag, the target can manually control locking of logical addresses. Signed-off-by: Matias Bjørling <m@bjorling.me> --- include/linux/blk_types.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)