From 1dba0ffec21e2c8ba16a52fe0d69dabb4d164089 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 11 Jun 2021 11:19:53 -0700 Subject: [PATCH] xfs_io: don't count fsmaps before querying fsmaps There's a bunch of code in fsmap.c that tries to count the GETFSMAP records so that it can size the fsmap array appropriately for the GETFSMAP call. It's pointless to iterate the entire result set /twice/ (unlike the bmap command where the extent count is actually stored in the fs metadata), so get rid of the duplicate walk. In other words: Iterate over the records using the default chunk size instead of doing one call to find the size and doing a giant allocation and GETFSMAP call. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- io/fsmap.c | 30 ------------------------------ 1 file changed, 30 deletions(-) diff --git a/io/fsmap.c b/io/fsmap.c index 9f179fa80..f540a7c04 100644 --- a/io/fsmap.c +++ b/io/fsmap.c @@ -372,13 +372,11 @@ fsmap_f( char **argv) { struct fsmap *p; - struct fsmap_head *nhead; struct fsmap_head *head; struct fsmap *l, *h; struct xfs_fsop_geom fsgeo; long long start = 0; long long end = -1; - int nmap_size; int map_size; int nflag = 0; int vflag = 0; @@ -492,34 +490,6 @@ fsmap_f( h->fmr_flags = UINT_MAX; h->fmr_offset = ULLONG_MAX; - /* Count mappings */ - if (!nflag) { - head->fmh_count = 0; - i = ioctl(file->fd, FS_IOC_GETFSMAP, head); - if (i < 0) { - fprintf(stderr, _("%s: xfsctl(XFS_IOC_GETFSMAP)" - " iflags=0x%x [\"%s\"]: %s\n"), - progname, head->fmh_iflags, file->name, - strerror(errno)); - exitcode = 1; - free(head); - return 0; - } - if (head->fmh_entries > map_size + 2) { - map_size = 11ULL * head->fmh_entries / 10; - nmap_size = map_size > (1 << 24) ? (1 << 24) : map_size; - nhead = realloc(head, fsmap_sizeof(nmap_size)); - if (nhead == NULL) { - fprintf(stderr, - _("%s: cannot realloc %zu bytes\n"), - progname, fsmap_sizeof(nmap_size)); - } else { - head = nhead; - map_size = nmap_size; - } - } - } - /* * If this is an XFS filesystem, remember the data device. * (We report AG number/block for data device extents on XFS). -- 2.47.3