If any of the iov operations return mid-block, use regular ops to complete the
current block and continue using iov ops.
Signed-off-by: Sasha Levin <levinsasha...@gmail.com>
---
tools/kvm/read-write.c | 58 ++++++++++++++++++++++++++++++++++++++++++-----
1 files changed, 51 insertions(+), 7 deletions(-)
diff --git a/tools/kvm/read-write.c b/tools/kvm/read-write.c
index 0c995c8..bf2e4a0 100644
--- a/tools/kvm/read-write.c
+++ b/tools/kvm/read-write.c
@@ -189,10 +189,10 @@ static inline ssize_t get_iov_size(const struct iovec
*iov, int iovcnt)
}
static inline void shift_iovec(const struct iovec **iov, int *iovcnt,
- size_t nr, ssize_t *total, size_t *count, off_t
*offset)
+ ssize_t *nr, ssize_t *total, size_t *count,
off_t *offset)
{
- while (nr >= (*iov)->iov_len) {
- nr -= (*iov)->iov_len;
+ while ((size_t)*nr >= (*iov)->iov_len) {
+ *nr -= (*iov)->iov_len;
*total += (*iov)->iov_len;
*count -= (*iov)->iov_len;
if (offset)
@@ -218,7 +218,18 @@ ssize_t readv_in_full(int fd, const struct iovec *iov, int
iovcnt)
return -1;
}
- shift_iovec(&iov, &iovcnt, nr, &total, &count, NULL);
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, NULL);
+
+ while (nr > 0) {
+ ssize_t nr_readagain;
+ nr_readagain = xread(fd, iov->iov_base + nr,
+
iov->iov_len - nr);
+ if (nr_readagain <= 0)
+ return total;
+
+ nr += nr_readagain;
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, NULL);
+ }
}
return total;
@@ -240,7 +251,18 @@ ssize_t writev_in_full(int fd, const struct iovec *iov,
int iovcnt)
return -1;
}
- shift_iovec(&iov, &iovcnt, nr, &total, &count, NULL);
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, NULL);
+
+ while (nr > 0) {
+ ssize_t nr_writeagain;
+ nr_writeagain = xwrite(fd, iov->iov_base + nr,
+
iov->iov_len - nr);
+ if (nr_writeagain <= 0)
+ return total;
+
+ nr += nr_writeagain;
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, NULL);
+ }
}
return total;
@@ -288,7 +310,18 @@ ssize_t preadv_in_full(int fd, const struct iovec *iov,
int iovcnt, off_t offset
return -1;
}
- shift_iovec(&iov, &iovcnt, nr, &total, &count, &offset);
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, &offset);
+
+ while (nr > 0) {
+ ssize_t nr_readagain;
+ nr_readagain = xpread(fd, iov->iov_base + nr,
+
iov->iov_len - nr, offset + nr);
+ if (nr_readagain <= 0)
+ return total;
+
+ nr += nr_readagain;
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count,
&offset);
+ }
}
return total;
@@ -310,7 +343,18 @@ ssize_t pwritev_in_full(int fd, const struct iovec *iov,
int iovcnt, off_t offse
return -1;
}
- shift_iovec(&iov, &iovcnt, nr, &total, &count, &offset);
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count, &offset);
+
+ while (nr > 0) {
+ ssize_t nr_writeagain;
+ nr_writeagain = xpread(fd, iov->iov_base + nr,
+
iov->iov_len - nr, offset + nr);
+ if (nr_writeagain <= 0)
+ return total;
+
+ nr += nr_writeagain;
+ shift_iovec(&iov, &iovcnt, &nr, &total, &count,
&offset);
+ }
}
return total;
--
1.7.5.rc1
--
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