This add discard support to mkfs.nilfs2 which will be useful to solid state devices or sparse/thin-provisioned storage.
The updated mkfs.nilfs2 will attempt to discard the device by default unless -K option is specified. Signed-off-by: Ryusuke Konishi <[email protected]> --- man/mkfs.nilfs2.8 | 11 ++++++ sbin/mkfs/mkfs.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 91 insertions(+), 8 deletions(-) diff --git a/man/mkfs.nilfs2.8 b/man/mkfs.nilfs2.8 index fb70c87..e9f7463 100644 --- a/man/mkfs.nilfs2.8 +++ b/man/mkfs.nilfs2.8 @@ -18,6 +18,9 @@ mkfs.nilfs2 \- create a NILFS2 filesystem .B \-c ] [ +.B \-K +] +[ .B \-L .I volume-label ] @@ -52,6 +55,9 @@ mkfs.nilfs2 \- create a NILFS2 filesystem .B \-c ] [ +.B \-K +] +[ .B \-L .I volume-label ] @@ -100,6 +106,11 @@ number of blocks per segment is 2048 (= 8MB with 4KB blocks). .B \-c Check the device for bad blocks before building the filesystem. .TP +.BI \-K +Keep, do not attempt to discard blocks at mkfs time (discarding blocks +initially is useful on solid state drives and sparse / +thinly-provisioned storage). +.TP .BI \-L " new-volume-label" Set the volume label for the filesystem to .IR new-volume-label\fP. diff --git a/sbin/mkfs/mkfs.c b/sbin/mkfs/mkfs.c index 95f4408..092edfd 100644 --- a/sbin/mkfs/mkfs.c +++ b/sbin/mkfs/mkfs.c @@ -109,6 +109,7 @@ static int quiet = 0; static int cflag = 0; static int nflag = 0; static int verbose = 0; +static int discard = 1; static unsigned long blocksize = NILFS_DEF_BLOCKSIZE; static unsigned long blocks_per_segment = NILFS_DEF_BLKS_PER_SEG; static unsigned long r_segments_percentage = NILFS_DEF_RESERVED_SEGMENTS; @@ -288,6 +289,55 @@ static void cannot_allocate_memory(void); static void too_small_segment(unsigned long, unsigned long); /* I/O routines */ +#ifdef __linux__ + +#ifndef BLKDISCARD +#define BLKDISCARD _IO(0x12,119) +#endif + +#ifndef BLKDISCARDZEROES +#define BLKDISCARDZEROES _IO(0x12,124) +#endif + +/** + * nilfs_mkfs_discard_range - issue discard command to the device + * @fd: file descriptor of the device + * @start: start offset of the region to discard (in bytes) + * @len: length of the region to discard (in bytes) + * + * Returns zero if the discard succeeds. Otherwise, -1 is returned. + */ +static int nilfs_mkfs_discard_range(int fd, __u64 start, __u64 len) +{ + __u64 range[2] = { start, len }; + int ret; + + ret = ioctl(fd, BLKDISCARD, &range); + if (verbose) { + pinfo("Discard device from %llu to %llu: %s.", + (unsigned long long)start, + (unsigned long long)start + len, + ret ? "failed" : "succeeded"); + } + return ret; +} + +/** + * nilfs_mkfs_discard_zeroes_data - get if discarded blocks are zeroed or not + * @fd: file descriptor of the device + */ +static int nilfs_mkfs_discard_zeroes_data(int fd) +{ + int discard_zeroes_data = 0; + + ioctl(fd, BLKDISCARDZEROES, &discard_zeroes_data); + return discard_zeroes_data; +} +#else +#define nilfs_mkfs_discard_range(fd, start, len) 1 +#define nilfs_mkfs_discard_zeroes_data(fd) 0 +#endif + static void disk_scan(const char *device); static void check_mount(int fd, const char *device); @@ -760,20 +810,39 @@ static int erase_disk_range(int fd, off_t offset, size_t count) static int erase_disk(int fd, struct nilfs_disk_info *di) { + const unsigned int sector_size = 512; + off_t start, end; int ret; - BUG_ON(di->dev_size < NILFS_DISK_ERASE_SIZE || - di->dev_size - NILFS_DISK_ERASE_SIZE < NILFS_SB_OFFSET_BYTES); + /* + * Define range of the partition that nilfs uses. This should + * not depend on the type of underlying device. + */ + start = NILFS_SB_OFFSET_BYTES; + end = di->dev_size & ~((__u64)sector_size - 1); + + BUG_ON(end < NILFS_DISK_ERASE_SIZE || + end - NILFS_DISK_ERASE_SIZE < start); + + if (discard) { + ret = nilfs_mkfs_discard_range(fd, start, end - start); + if (!ret && nilfs_mkfs_discard_zeroes_data(fd)) { + if (verbose) + pinfo("Discard succeeded and will return 0s " + " - skip wiping"); + goto out; + } + } /* Erase tail of partition */ - ret = erase_disk_range(fd, di->dev_size - NILFS_DISK_ERASE_SIZE, + ret = erase_disk_range(fd, end - NILFS_DISK_ERASE_SIZE, NILFS_DISK_ERASE_SIZE); if (ret == 0) { /* Erase head of partition */ - ret = erase_disk_range(fd, NILFS_SB_OFFSET_BYTES, - NILFS_DISK_ERASE_SIZE - - NILFS_SB_OFFSET_BYTES); + ret = erase_disk_range(fd, start, + NILFS_DISK_ERASE_SIZE - start); } +out: return ret; } @@ -877,7 +946,7 @@ static void parse_options(int argc, char *argv[]) { int c, show_version_only = 0; - while ((c = getopt(argc, argv, "b:B:cL:m:nqvVP:")) != EOF) { + while ((c = getopt(argc, argv, "b:B:cKL:m:nqvVP:")) != EOF) { switch (c) { case 'b': blocksize = atol(optarg); @@ -889,6 +958,9 @@ static void parse_options(int argc, char *argv[]) case 'c': cflag++; break; + case 'K': + discard = 0; + break; case 'L': strncpy(volume_label, optarg, sizeof(volume_label)); break; @@ -945,7 +1017,7 @@ static void usage(void) fprintf(stderr, "Usage: %s [-b block-size] [-B blocks-per-segment] [-c] \n" "[-L volume-label] [-m reserved-segments-percentage] \n" - "[-nqvV] device\n", + "[-nqvKV] device\n", progname); exit(1); } -- 1.7.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
