diff options
Diffstat (limited to 'usr/src/uts/common/fs/zfs/sys/spa.h')
| -rw-r--r-- | usr/src/uts/common/fs/zfs/sys/spa.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/usr/src/uts/common/fs/zfs/sys/spa.h b/usr/src/uts/common/fs/zfs/sys/spa.h index 4f4eb15318..6a7e13b819 100644 --- a/usr/src/uts/common/fs/zfs/sys/spa.h +++ b/usr/src/uts/common/fs/zfs/sys/spa.h @@ -124,6 +124,17 @@ _NOTE(CONSTCOND) } while (0) #define SPA_MAXBLOCKSIZE (1ULL << SPA_MAXBLOCKSHIFT) /* + * Alignment Shift (ashift) is an immutable, internal top-level vdev property + * which can only be set at vdev creation time. Physical writes are always done + * according to it, which makes 2^ashift the smallest possible IO on a vdev. + * + * We currently allow values ranging from 512 bytes (2^9 = 512) to 64 KiB + * (2^16 = 65,536). + */ +#define ASHIFT_MIN 9 +#define ASHIFT_MAX 16 + +/* * Size of block to hold the configuration data (a packed nvlist) */ #define SPA_CONFIG_BLOCKSIZE (1ULL << 14) |