From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
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 <rgoldwyn@xxxxxxxx>
---
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
--
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