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iov: don't touch iov in iov_send_recv()

PATCH Applied Wen Congyang 3 participants 5 messages May 21, 2015 – Jun 23, 2015

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#0 lore raw

PATCH 1/1 iov: don't touch iov in iov_send_recv()

---
 include/qemu/iov.h |  2 +-
 util/iov.c         | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)
include/qemu/iov.h +1 -1
index 68d25f2..569b2c2 100644
@@ -75,7 +75,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  * For iov_send_recv() _whole_ area being sent or received
  * should be within the iovec, not only beginning of it.
  */
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes, bool do_send);
 #define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \
   iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false)
util/iov.c +13 -1
index 2fb18e6..a0d5934 100644
@@ -133,7 +133,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 #endif
 }
 
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
@@ -141,6 +141,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
     ssize_t ret;
     size_t orig_len, tail;
     unsigned niov;
+    struct iovec *local_iov, *iov;
+
+    if (bytes <= 0) {
+        return 0;
+    }
+
+    local_iov = g_new0(struct iovec, iov_cnt);
+    iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+    offset = 0;
+    iov = local_iov;
 
     while (bytes > 0) {
         /* Find the start position, skipping `offset' bytes:
@@ -187,6 +197,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 
         if (ret < 0) {
             assert(errno != EINTR);
+            g_free(local_iov);
             if (errno == EAGAIN && total > 0) {
                 return total;
             }
@@ -205,6 +216,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
         bytes -= ret;
     }
 
+    g_free(local_iov);
     return total;
 }
 
Signature · 1 line
2.1.0
#1 lore raw

Ping...

Quoted 66 lines · Wen Congyang
---
 include/qemu/iov.h |  2 +-
 util/iov.c         | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)
include/qemu/iov.h +1 -1
index 68d25f2..569b2c2 100644
@@ -75,7 +75,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  * For iov_send_recv() _whole_ area being sent or received
  * should be within the iovec, not only beginning of it.
  */
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes, bool do_send);
 #define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \
   iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false)
util/iov.c +13 -1
index 2fb18e6..a0d5934 100644
@@ -133,7 +133,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 #endif
 }
 
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
@@ -141,6 +141,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
     ssize_t ret;
     size_t orig_len, tail;
     unsigned niov;
+    struct iovec *local_iov, *iov;
+
+    if (bytes <= 0) {
+        return 0;
+    }
+
+    local_iov = g_new0(struct iovec, iov_cnt);
+    iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+    offset = 0;
+    iov = local_iov;
 
     while (bytes > 0) {
         /* Find the start position, skipping `offset' bytes:
@@ -187,6 +197,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 
         if (ret < 0) {
             assert(errno != EINTR);
+            g_free(local_iov);
             if (errno == EAGAIN && total > 0) {
                 return total;
             }
@@ -205,6 +216,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
         bytes -= ret;
     }
 
+    g_free(local_iov);
     return total;
 }
 
#2 lore raw
Quoted 1 line · * Wen Congyang ([email protected]) wrote:

Ping...

Hi Wen,
I don't know the block side of stuff to review this stuff, so
I'll leave it to Kevin and Paolo.

Dave

Quoted 63 lines · Wen Congyang
Quoted 61 lines
---
 include/qemu/iov.h |  2 +-
 util/iov.c         | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)
include/qemu/iov.h +1 -1
index 68d25f2..569b2c2 100644
@@ -75,7 +75,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  * For iov_send_recv() _whole_ area being sent or received
  * should be within the iovec, not only beginning of it.
  */
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes, bool do_send);
 #define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \
   iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false)
util/iov.c +12 -1
index 2fb18e6..a0d5934 100644
@@ -133,7 +133,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 #endif
 }
 
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
@@ -141,6 +141,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
     ssize_t ret;
     size_t orig_len, tail;
     unsigned niov;
+    struct iovec *local_iov, *iov;
+
+    if (bytes <= 0) {
+        return 0;
+    }
+
+    local_iov = g_new0(struct iovec, iov_cnt);
+    iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+    offset = 0;
+    iov = local_iov;
 
     while (bytes > 0) {
         /* Find the start position, skipping `offset' bytes:
@@ -187,6 +197,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 
         if (ret < 0) {
             assert(errno != EINTR);
+            g_free(local_iov);
             if (errno == EAGAIN && total > 0) {
                 return total;
             }
@@ -205,6 +216,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
         bytes -= ret;
     }
 
Quoted 6 lines

util/iov.c ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, · line 222

Quoted 5 lines
util/iov.c +1 -0
+    g_free(local_iov);
     return total;
 }
 

--
Dr. David Alan Gilbert / [email protected] / Manchester, UK

#3 lore raw
In reply to Wen Congyang

Ping again.

This patch is bugfix. The old discussion is here:
http://lists.nongnu.org/archive/html/qemu-devel/2015-02/msg00245.html

Quoted 66 lines · Wen Congyang
---
 include/qemu/iov.h |  2 +-
 util/iov.c         | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)
include/qemu/iov.h +1 -1
index 68d25f2..569b2c2 100644
@@ -75,7 +75,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  * For iov_send_recv() _whole_ area being sent or received
  * should be within the iovec, not only beginning of it.
  */
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes, bool do_send);
 #define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \
   iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false)
util/iov.c +13 -1
index 2fb18e6..a0d5934 100644
@@ -133,7 +133,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
 #endif
 }
 
-ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
+ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
                       size_t offset, size_t bytes,
                       bool do_send)
 {
@@ -141,6 +141,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
     ssize_t ret;
     size_t orig_len, tail;
     unsigned niov;
+    struct iovec *local_iov, *iov;
+
+    if (bytes <= 0) {
+        return 0;
+    }
+
+    local_iov = g_new0(struct iovec, iov_cnt);
+    iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
+    offset = 0;
+    iov = local_iov;
 
     while (bytes > 0) {
         /* Find the start position, skipping `offset' bytes:
@@ -187,6 +197,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 
         if (ret < 0) {
             assert(errno != EINTR);
+            g_free(local_iov);
             if (errno == EAGAIN && total > 0) {
                 return total;
             }
@@ -205,6 +216,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
         bytes -= ret;
     }
 
+    g_free(local_iov);
     return total;
 }