From ad136b3382919e93cc692b54f735fad8b35e88fe Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 14 Oct 2009 00:28:52 +0200 Subject: [PATCH] mkfs: add discard support Call the BLKDISCARD ioctl to mark the whole disk as unused before creating a new filesystem. This will allow SSDs, Arrays with thin provisioning support and virtual machines to make smarter allocation decisions. Add a new -K option to prevent mkfs from discarding blocks to aid trouble-shooting or specialized requirements. Signed-off-by: Christoph Hellwig Reviewed-by: Eric Sandeen Reviewed-by: Andi Kleen --- include/darwin.h | 6 ++++++ include/freebsd.h | 6 ++++++ include/irix.h | 6 ++++++ include/linux.h | 14 ++++++++++++++ man/man8/mkfs.xfs.8 | 5 +++++ mkfs/xfs_mkfs.c | 28 +++++++++++++++++++++++++++- 6 files changed, 64 insertions(+), 1 deletion(-) diff --git a/include/darwin.h b/include/darwin.h index 25cd61841..69c032277 100644 --- a/include/darwin.h +++ b/include/darwin.h @@ -154,4 +154,10 @@ typedef unsigned char uchar_t; #define HAVE_FID 1 +static __inline__ int +platform_discard_blocks(int fd, off64_t start, off64_t end) +{ + return 0; +} + #endif /* __XFS_DARWIN_H__ */ diff --git a/include/freebsd.h b/include/freebsd.h index 967ca25f2..7089dd97c 100644 --- a/include/freebsd.h +++ b/include/freebsd.h @@ -139,4 +139,10 @@ static __inline__ void platform_uuid_copy(uuid_t *dst, uuid_t *src) memcpy(dst, src, sizeof(uuid_t)); } +static __inline__ int +platform_discard_blocks(int fd, off64_t start, off64_t end) +{ + return 0; +} + #endif /* __XFS_FREEBSD_H__ */ diff --git a/include/irix.h b/include/irix.h index a7debd3e9..f75193939 100644 --- a/include/irix.h +++ b/include/irix.h @@ -337,6 +337,12 @@ static __inline__ void platform_uuid_copy(uuid_t *dst, uuid_t *src) memcpy(dst, src, sizeof(uuid_t)); } +static __inline__ int +platform_discard_blocks(int fd, off64_t start, off64_t end) +{ + return 0; +} + static __inline__ char * strsep(char **s, const char *ct) { char *sbegin = *s, *end; diff --git a/include/linux.h b/include/linux.h index 1bb5866d6..048648513 100644 --- a/include/linux.h +++ b/include/linux.h @@ -93,6 +93,20 @@ static __inline__ void platform_uuid_copy(uuid_t *dst, uuid_t *src) uuid_copy(*dst, *src); } +#ifndef BLKDISCARD +#define BLKDISCARD _IO(0x12,119) +#endif + +static __inline__ int +platform_discard_blocks(int fd, off64_t start, off64_t end) +{ + __uint64_t range[2] = { start, end }; + + if (ioctl(fd, BLKDISCARD, &range) < 0) + return errno; + return 0; +} + #if (__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ <= 1)) # define constpp const char * const * #else diff --git a/man/man8/mkfs.xfs.8 b/man/man8/mkfs.xfs.8 index 74a98db38..40ea1bd70 100644 --- a/man/man8/mkfs.xfs.8 +++ b/man/man8/mkfs.xfs.8 @@ -36,6 +36,8 @@ mkfs.xfs \- construct an XFS filesystem .I label ] [ .B \-N +] [ +.B \-K ] .I device .SH DESCRIPTION @@ -714,6 +716,9 @@ manual entries for additional information. .B \-N Causes the file system parameters to be printed out without really creating the file system. +.TP +.B \-K +Do not attempt to discard blocks at mkfs time. .SH SEE ALSO .BR xfs (5), .BR mkfs (8), diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c index 75ad20c52..bd92bc00f 100644 --- a/mkfs/xfs_mkfs.c +++ b/mkfs/xfs_mkfs.c @@ -736,6 +736,20 @@ done: free(buf); } +static void +discard_blocks(dev_t dev, __uint64_t nsectors) +{ + int fd; + + /* + * We intentionally ignore errors from the discard ioctl. It is + * not necessary for the mkfs functionality but just an optimization. + */ + fd = libxfs_device_to_fd(dev); + if (fd > 0) + platform_discard_blocks(fd, 0, nsectors << 9); +} + int main( int argc, @@ -812,6 +826,7 @@ main( int nvflag; int nci; int Nflag; + int discard = 1; char *p; char *protofile; char *protostring; @@ -870,7 +885,7 @@ main( xi.isdirect = LIBXFS_DIRECT; xi.isreadonly = LIBXFS_EXCLUSIVELY; - while ((c = getopt(argc, argv, "b:d:i:l:L:n:Np:qr:s:CfV")) != EOF) { + while ((c = getopt(argc, argv, "b:d:i:l:L:n:KNp:qr:s:CfV")) != EOF) { switch (c) { case 'C': case 'f': @@ -1386,6 +1401,9 @@ main( case 'N': Nflag = 1; break; + case 'K': + discard = 0; + break; case 'p': if (protofile) respec('p', NULL, 0); @@ -1773,6 +1791,14 @@ main( } } + if (discard) { + discard_blocks(xi.ddev, xi.dsize); + if (xi.rtdev) + discard_blocks(xi.rtdev, xi.rtsize); + if (xi.logdev && xi.logdev != xi.ddev) + discard_blocks(xi.logdev, xi.logBBsize); + } + if (!liflag && !ldflag) loginternal = xi.logdev == 0; if (xi.logname) -- 2.47.2