From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:46626 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754227AbdJIPDA (ORCPT ); Mon, 9 Oct 2017 11:03:00 -0400 Date: Mon, 9 Oct 2017 11:02:58 -0400 From: Brian Foster Subject: Re: [PATCH v2 3/3] xfs_io: Allow partial writes Message-ID: <20171009150258.GC19322@bfoster.bfoster> References: <20170929130035.24760-1-rgoldwyn@suse.de> <20170929130035.24760-3-rgoldwyn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170929130035.24760-3-rgoldwyn@suse.de> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Goldwyn Rodrigues Cc: linux-xfs@vger.kernel.org, darrick.wong@oracle.com, david@fromorbit.com, Goldwyn Rodrigues On Fri, Sep 29, 2017 at 08:00:35AM -0500, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues > > Partial writes are performed when there is an error midway > while performing the I/O. Perform the write exactly once and > return the number of bytes written so far, until the error. > > Signed-off-by: Goldwyn Rodrigues > --- Reviewed-by: Brian Foster > io/io.h | 1 + > io/pwrite.c | 25 ++++++++++++++++++++++++- > man/man8/xfs_io.8 | 3 +++ > 3 files changed, 28 insertions(+), 1 deletion(-) > > diff --git a/io/io.h b/io/io.h > index 6a0fe657..3862985f 100644 > --- a/io/io.h > +++ b/io/io.h > @@ -25,6 +25,7 @@ > #define IO_RANDOM ( 0) > #define IO_FORWARD ( 1) > #define IO_BACKWARD (-1) > +#define IO_ONCE ( 2) > > /* > * File descriptor options > diff --git a/io/pwrite.c b/io/pwrite.c > index 2b85a528..dcf130d6 100644 > --- a/io/pwrite.c > +++ b/io/pwrite.c > @@ -47,6 +47,7 @@ pwrite_help(void) > " -W -- call fsync(2) at the end (included in timing results)\n" > " -B -- write backwards through the range from offset (backwards N bytes)\n" > " -F -- write forwards through the range of bytes from offset (default)\n" > +" -O -- perform pwrite call once and return (maybe partial) bytes written\n" > " -R -- write at random offsets in the specified range of bytes\n" > " -Z N -- zeed the random number generator (used when writing randomly)\n" > " (heh, zorry, the -s/-S arguments were already in use in pwrite)\n" > @@ -258,6 +259,22 @@ write_buffer( > return ops; > } > > +static int > +write_once( > + off64_t offset, > + long long count, > + long long *total, > + int pwritev2_flags) > +{ > + size_t bytes; > + bytes = do_pwrite(file->fd, offset, count, count, pwritev2_flags); > + if (bytes < 0) > + return -1; > + *total = bytes; > + return 1; > +} > + > + > static int > pwrite_f( > int argc, > @@ -279,7 +296,7 @@ pwrite_f( > init_cvtnum(&fsblocksize, &fssectsize); > bsize = fsblocksize; > > - while ((c = getopt(argc, argv, "b:BCdf:Fi:NqRs:S:uV:wWZ:")) != EOF) { > + while ((c = getopt(argc, argv, "b:BCdf:Fi:NqRs:OS:uV:wWZ:")) != EOF) { > switch (c) { > case 'b': > tmp = cvtnum(fsblocksize, fssectsize, optarg); > @@ -301,6 +318,9 @@ pwrite_f( > case 'R': > direction = IO_RANDOM; > break; > + case 'O': > + direction = IO_ONCE; > + break; > case 'd': > dflag = 1; > break; > @@ -392,6 +412,9 @@ pwrite_f( > case IO_BACKWARD: > c = write_backward(offset, &count, &total, pwritev2_flags); > break; > + case IO_ONCE: > + c = write_once(offset, count, &total, pwritev2_flags); > + break; > default: > total = 0; > ASSERT(0); > diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 > index 9c58914f..b7c0f099 100644 > --- a/man/man8/xfs_io.8 > +++ b/man/man8/xfs_io.8 > @@ -263,6 +263,9 @@ write the buffers in a reserve sequential direction. > .B \-R > write the buffers in the give range in a random order. > .TP > +.B \-O > +perform pwrite once and return the (maybe partial) bytes written. > +.TP > .B \-Z seed > specify the random number seed used for random write > .TP > -- > 2.14.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html