Hackily use a NULL buffer for the pwrite command to induce a kernel write syscall failure. This is posted for reference only and needs a proper implementation: needs a new flag, probably should be wired through alloc_buffer(), etc. Not-Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx> --- Posted in prototype form in reference to the discussion here: https://lore.kernel.org/linux-xfs/Y3e+7XH5gq5gc97u@bfoster/ Brian io/pwrite.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/io/pwrite.c b/io/pwrite.c index 467bfa9f8..6e5de3140 100644 --- a/io/pwrite.c +++ b/io/pwrite.c @@ -285,12 +285,14 @@ pwrite_f( int direction = IO_FORWARD; int c, fd = -1; int pwritev2_flags = 0; + bool fail = false; + char *orig_io_buffer = NULL; Cflag = qflag = uflag = dflag = wflag = Wflag = 0; init_cvtnum(&fsblocksize, &fssectsize); bsize = fsblocksize; - while ((c = getopt(argc, argv, "b:BCdDf:Fi:NqRs:OS:uV:wWZ:")) != EOF) { + while ((c = getopt(argc, argv, "b:BCdDfFi:NqRs:OS:uV:wWZ:")) != EOF) { switch (c) { case 'b': tmp = cvtnum(fsblocksize, fssectsize, optarg); @@ -320,6 +322,8 @@ pwrite_f( dflag = 1; break; case 'f': + fail = true; + break; case 'i': infile = optarg; break; @@ -414,6 +418,10 @@ pwrite_f( exitcode = 1; return 0; } + if (fail) { + orig_io_buffer = io_buffer; + io_buffer = NULL; + } c = IO_READONLY | (dflag ? IO_DIRECT : 0); if (infile && ((fd = openfile(infile, NULL, c, 0, NULL)) < 0)) { @@ -471,6 +479,8 @@ pwrite_f( done: if (infile) close(fd); + if (orig_io_buffer) + io_buffer = orig_io_buffer; return 0; } -- 2.37.3
