[Virtio-fs] [PATCH v2 0/7] virtiofsd: Few cleanups in virtio_send_data_iov()

[Virtio-fs] [PATCH v2 0/7] virtiofsd: Few cleanups in virtio_send_data_iov()

[Vivek Goyal]

Hi,

This is V2 of the patches. Changes since V1 are.

- Took care of coding style issue.
- Got rid of label "err" completely in last patch. (Dave, Connor). 
- Captured Reviewed-by tags from Connor and David.

Code in virtio_send_data_iov() little twisted and complicated. This
patch series just tries to simplify it a bit to make it little easier
to read this piece of code.

Thanks
Vivek


Vivek Goyal (7):
  virtiofsd: Check for EINTR in preadv() and retry
  virtiofsd: Get rid of unreachable code in read
  virtiofsd: Use iov_discard_front() to skip bytes
  virtiofsd: get rid of in_sg_left variable
  virtiofsd: Simplify skip byte logic
  virtiofsd: Check EOF before short read
  virtiofsd: Set req->reply_sent right after sending reply

 tools/virtiofsd/fuse_virtio.c | 81 +++++++++++------------------------
 1 file changed, 25 insertions(+), 56 deletions(-)

-- 
2.25.4

[PATCH v2 0/7] virtiofsd: Few cleanups in virtio_send_data_iov()

[Vivek Goyal]

Hi,

This is V2 of the patches. Changes since V1 are.

- Took care of coding style issue.
- Got rid of label "err" completely in last patch. (Dave, Connor). 
- Captured Reviewed-by tags from Connor and David.

Code in virtio_send_data_iov() little twisted and complicated. This
patch series just tries to simplify it a bit to make it little easier
to read this piece of code.

Thanks
Vivek


Vivek Goyal (7):
  virtiofsd: Check for EINTR in preadv() and retry
  virtiofsd: Get rid of unreachable code in read
  virtiofsd: Use iov_discard_front() to skip bytes
  virtiofsd: get rid of in_sg_left variable
  virtiofsd: Simplify skip byte logic
  virtiofsd: Check EOF before short read
  virtiofsd: Set req->reply_sent right after sending reply

 tools/virtiofsd/fuse_virtio.c | 81 +++++++++++------------------------
 1 file changed, 25 insertions(+), 56 deletions(-)

-- 
2.25.4

[Virtio-fs] [PATCH v2 1/7] virtiofsd: Check for EINTR in preadv() and retry

[Vivek Goyal]

We don't seem to check for EINTR and retry. There are other places
in code where we check for EINTR. So lets add a check.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 9efdbd8ffd..755d7fb25c 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -421,6 +421,9 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
 
         if (ret == -1) {
             ret = errno;
+            if (ret == EINTR) {
+                continue;
+            }
             fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n",
                      __func__, len);
             goto err;
-- 
2.25.4

[PATCH v2 1/7] virtiofsd: Check for EINTR in preadv() and retry

[Vivek Goyal]

We don't seem to check for EINTR and retry. There are other places
in code where we check for EINTR. So lets add a check.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 9efdbd8ffd..755d7fb25c 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -421,6 +421,9 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
 
         if (ret == -1) {
             ret = errno;
+            if (ret == EINTR) {
+                continue;
+            }
             fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n",
                      __func__, len);
             goto err;
-- 
2.25.4

[Virtio-fs] [PATCH v2 2/7] virtiofsd: Get rid of unreachable code in read

[Vivek Goyal]

pvreadv() can return following.

- error
- 0 in case of EOF
- short read

We seem to handle all the cases already. We are retrying read in case
of short read. So another check for short read seems like dead code.
Get rid of it.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 755d7fb25c..28e2974d1a 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -446,11 +446,6 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
                      in_sg_left);
             break;
         }
-        if (ret != len) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret!=len\n", __func__);
-            ret = EIO;
-            goto err;
-        }
         in_sg_left -= ret;
         len -= ret;
     } while (in_sg_left);
-- 
2.25.4

[PATCH v2 2/7] virtiofsd: Get rid of unreachable code in read

[Vivek Goyal]

pvreadv() can return following.

- error
- 0 in case of EOF
- short read

We seem to handle all the cases already. We are retrying read in case
of short read. So another check for short read seems like dead code.
Get rid of it.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 755d7fb25c..28e2974d1a 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -446,11 +446,6 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
                      in_sg_left);
             break;
         }
-        if (ret != len) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret!=len\n", __func__);
-            ret = EIO;
-            goto err;
-        }
         in_sg_left -= ret;
         len -= ret;
     } while (in_sg_left);
-- 
2.25.4

[Virtio-fs] [PATCH v2 3/7] virtiofsd: Use iov_discard_front() to skip bytes

[Vivek Goyal]

There are places where we need to skip few bytes from front of the iovec
array. We have our own custom code for that. Looks like iov_discard_front()
can do same thing. So use that helper instead.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 28e2974d1a..09674f2e90 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -389,23 +389,15 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     memcpy(in_sg_cpy, in_sg, sizeof(struct iovec) * in_num);
     /* These get updated as we skip */
     struct iovec *in_sg_ptr = in_sg_cpy;
-    int in_sg_cpy_count = in_num;
+    unsigned int in_sg_cpy_count = in_num;
 
     /* skip over parts of in_sg that contained the header iov */
     size_t skip_size = iov_len;
 
     size_t in_sg_left = 0;
     do {
-        while (skip_size != 0 && in_sg_cpy_count) {
-            if (skip_size >= in_sg_ptr[0].iov_len) {
-                skip_size -= in_sg_ptr[0].iov_len;
-                in_sg_ptr++;
-                in_sg_cpy_count--;
-            } else {
-                in_sg_ptr[0].iov_len -= skip_size;
-                in_sg_ptr[0].iov_base += skip_size;
-                break;
-            }
+        if (skip_size != 0) {
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
         }
 
         int i;
-- 
2.25.4

[PATCH v2 3/7] virtiofsd: Use iov_discard_front() to skip bytes

[Vivek Goyal]

There are places where we need to skip few bytes from front of the iovec
array. We have our own custom code for that. Looks like iov_discard_front()
can do same thing. So use that helper instead.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 28e2974d1a..09674f2e90 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -389,23 +389,15 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     memcpy(in_sg_cpy, in_sg, sizeof(struct iovec) * in_num);
     /* These get updated as we skip */
     struct iovec *in_sg_ptr = in_sg_cpy;
-    int in_sg_cpy_count = in_num;
+    unsigned int in_sg_cpy_count = in_num;
 
     /* skip over parts of in_sg that contained the header iov */
     size_t skip_size = iov_len;
 
     size_t in_sg_left = 0;
     do {
-        while (skip_size != 0 && in_sg_cpy_count) {
-            if (skip_size >= in_sg_ptr[0].iov_len) {
-                skip_size -= in_sg_ptr[0].iov_len;
-                in_sg_ptr++;
-                in_sg_cpy_count--;
-            } else {
-                in_sg_ptr[0].iov_len -= skip_size;
-                in_sg_ptr[0].iov_base += skip_size;
-                break;
-            }
+        if (skip_size != 0) {
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
         }
 
         int i;
-- 
2.25.4

[Virtio-fs] [PATCH v2 4/7] virtiofsd: get rid of in_sg_left variable

[Vivek Goyal]

in_sg_left seems to be being used primarly for debugging purpose. It is
keeping track of how many bytes are left in the scatter list we are
reading into.

We already have another variable "len" which keeps track how many bytes
are left to be read. And in_sg_left is greater than or equal to len. We
have already ensured that in the beginning of function.

    if (in_len < tosend_len) {
        fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n",
                 __func__, elem->index, tosend_len);
        ret = E2BIG;
        goto err;
    }

So in_sg_left seems like a redundant variable. It probably was useful for
debugging when code was being developed. Get rid of it. It helps simplify
this function.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 09674f2e90..ed5146d7a6 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -394,20 +394,16 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     /* skip over parts of in_sg that contained the header iov */
     size_t skip_size = iov_len;
 
-    size_t in_sg_left = 0;
     do {
         if (skip_size != 0) {
             iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
         }
 
-        int i;
-        for (i = 0, in_sg_left = 0; i < in_sg_cpy_count; i++) {
-            in_sg_left += in_sg_ptr[i].iov_len;
-        }
         fuse_log(FUSE_LOG_DEBUG,
                  "%s: after skip skip_size=%zd in_sg_cpy_count=%d "
-                 "in_sg_left=%zd\n",
-                 __func__, skip_size, in_sg_cpy_count, in_sg_left);
+                 "len remaining=%zd\n", __func__, skip_size, in_sg_cpy_count,
+                 len);
+
         ret = preadv(buf->buf[0].fd, in_sg_ptr, in_sg_cpy_count,
                      buf->buf[0].pos);
 
@@ -434,13 +430,12 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         }
         if (!ret) {
             /* EOF case? */
-            fuse_log(FUSE_LOG_DEBUG, "%s: !ret in_sg_left=%zd\n", __func__,
-                     in_sg_left);
+            fuse_log(FUSE_LOG_DEBUG, "%s: !ret len remaining=%zd\n", __func__,
+                     len);
             break;
         }
-        in_sg_left -= ret;
         len -= ret;
-    } while (in_sg_left);
+    } while (len);
 
     /* Need to fix out->len on EOF */
     if (len) {
-- 
2.25.4

[PATCH v2 4/7] virtiofsd: get rid of in_sg_left variable

[Vivek Goyal]

in_sg_left seems to be being used primarly for debugging purpose. It is
keeping track of how many bytes are left in the scatter list we are
reading into.

We already have another variable "len" which keeps track how many bytes
are left to be read. And in_sg_left is greater than or equal to len. We
have already ensured that in the beginning of function.

    if (in_len < tosend_len) {
        fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n",
                 __func__, elem->index, tosend_len);
        ret = E2BIG;
        goto err;
    }

So in_sg_left seems like a redundant variable. It probably was useful for
debugging when code was being developed. Get rid of it. It helps simplify
this function.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 09674f2e90..ed5146d7a6 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -394,20 +394,16 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     /* skip over parts of in_sg that contained the header iov */
     size_t skip_size = iov_len;
 
-    size_t in_sg_left = 0;
     do {
         if (skip_size != 0) {
             iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
         }
 
-        int i;
-        for (i = 0, in_sg_left = 0; i < in_sg_cpy_count; i++) {
-            in_sg_left += in_sg_ptr[i].iov_len;
-        }
         fuse_log(FUSE_LOG_DEBUG,
                  "%s: after skip skip_size=%zd in_sg_cpy_count=%d "
-                 "in_sg_left=%zd\n",
-                 __func__, skip_size, in_sg_cpy_count, in_sg_left);
+                 "len remaining=%zd\n", __func__, skip_size, in_sg_cpy_count,
+                 len);
+
         ret = preadv(buf->buf[0].fd, in_sg_ptr, in_sg_cpy_count,
                      buf->buf[0].pos);
 
@@ -434,13 +430,12 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         }
         if (!ret) {
             /* EOF case? */
-            fuse_log(FUSE_LOG_DEBUG, "%s: !ret in_sg_left=%zd\n", __func__,
-                     in_sg_left);
+            fuse_log(FUSE_LOG_DEBUG, "%s: !ret len remaining=%zd\n", __func__,
+                     len);
             break;
         }
-        in_sg_left -= ret;
         len -= ret;
-    } while (in_sg_left);
+    } while (len);
 
     /* Need to fix out->len on EOF */
     if (len) {
-- 
2.25.4

[Virtio-fs] [PATCH v2 5/7] virtiofsd: Simplify skip byte logic

[Vivek Goyal]

We need to skip bytes in two cases.

a. Before we start reading into in_sg, we need to skip iov_len bytes
   in the beginning which typically will have fuse_out_header.

b. If preadv() does a short read, then we need to retry preadv() with
   remainig bytes and skip the bytes preadv() read in short read.

For case a, there is no reason that skipping logic be inside the while
loop. Move it outside. And only retain logic "b" inside while loop.

Also get rid of variable "skip_size". Looks like we can do without it.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index ed5146d7a6..49c7dd788a 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -392,17 +392,11 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     unsigned int in_sg_cpy_count = in_num;
 
     /* skip over parts of in_sg that contained the header iov */
-    size_t skip_size = iov_len;
+    iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, iov_len);
 
     do {
-        if (skip_size != 0) {
-            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
-        }
-
-        fuse_log(FUSE_LOG_DEBUG,
-                 "%s: after skip skip_size=%zd in_sg_cpy_count=%d "
-                 "len remaining=%zd\n", __func__, skip_size, in_sg_cpy_count,
-                 len);
+        fuse_log(FUSE_LOG_DEBUG, "%s: in_sg_cpy_count=%d len remaining=%zd\n",
+                 __func__, in_sg_cpy_count, len);
 
         ret = preadv(buf->buf[0].fd, in_sg_ptr, in_sg_cpy_count,
                      buf->buf[0].pos);
@@ -421,7 +415,7 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         if (ret < len && ret) {
             fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
             /* Skip over this much next time around */
-            skip_size = ret;
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
             buf->buf[0].pos += ret;
             len -= ret;
 
-- 
2.25.4

[PATCH v2 5/7] virtiofsd: Simplify skip byte logic

[Vivek Goyal]

We need to skip bytes in two cases.

a. Before we start reading into in_sg, we need to skip iov_len bytes
   in the beginning which typically will have fuse_out_header.

b. If preadv() does a short read, then we need to retry preadv() with
   remainig bytes and skip the bytes preadv() read in short read.

For case a, there is no reason that skipping logic be inside the while
loop. Move it outside. And only retain logic "b" inside while loop.

Also get rid of variable "skip_size". Looks like we can do without it.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index ed5146d7a6..49c7dd788a 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -392,17 +392,11 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     unsigned int in_sg_cpy_count = in_num;
 
     /* skip over parts of in_sg that contained the header iov */
-    size_t skip_size = iov_len;
+    iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, iov_len);
 
     do {
-        if (skip_size != 0) {
-            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, skip_size);
-        }
-
-        fuse_log(FUSE_LOG_DEBUG,
-                 "%s: after skip skip_size=%zd in_sg_cpy_count=%d "
-                 "len remaining=%zd\n", __func__, skip_size, in_sg_cpy_count,
-                 len);
+        fuse_log(FUSE_LOG_DEBUG, "%s: in_sg_cpy_count=%d len remaining=%zd\n",
+                 __func__, in_sg_cpy_count, len);
 
         ret = preadv(buf->buf[0].fd, in_sg_ptr, in_sg_cpy_count,
                      buf->buf[0].pos);
@@ -421,7 +415,7 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         if (ret < len && ret) {
             fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
             /* Skip over this much next time around */
-            skip_size = ret;
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
             buf->buf[0].pos += ret;
             len -= ret;
 
-- 
2.25.4

[Virtio-fs] [PATCH v2 6/7] virtiofsd: Check EOF before short read

[Vivek Goyal]

In virtio_send_data_iov() we are checking first for short read and then
EOF condition. Change the order. Basically check for error and EOF first
and last remaining piece is short ready which will lead to retry
automatically at the end of while loop.

Just that it is little simpler to read to the code. There is no need
to call "continue" and also one less call of "len-=ret".

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 49c7dd788a..99f91c9d87 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -410,25 +410,24 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
                      __func__, len);
             goto err;
         }
-        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
-                 ret, len);
-        if (ret < len && ret) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
-            /* Skip over this much next time around */
-            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
-            buf->buf[0].pos += ret;
-            len -= ret;
 
-            /* Lets do another read */
-            continue;
-        }
         if (!ret) {
             /* EOF case? */
             fuse_log(FUSE_LOG_DEBUG, "%s: !ret len remaining=%zd\n", __func__,
                      len);
             break;
         }
+        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
+                 ret, len);
+
         len -= ret;
+        /* Short read. Retry reading remaining bytes */
+        if (len) {
+            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
+            /* Skip over this much next time around */
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
+            buf->buf[0].pos += ret;
+        }
     } while (len);
 
     /* Need to fix out->len on EOF */
-- 
2.25.4

[PATCH v2 6/7] virtiofsd: Check EOF before short read

[Vivek Goyal]

In virtio_send_data_iov() we are checking first for short read and then
EOF condition. Change the order. Basically check for error and EOF first
and last remaining piece is short ready which will lead to retry
automatically at the end of while loop.

Just that it is little simpler to read to the code. There is no need
to call "continue" and also one less call of "len-=ret".

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 49c7dd788a..99f91c9d87 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -410,25 +410,24 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
                      __func__, len);
             goto err;
         }
-        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
-                 ret, len);
-        if (ret < len && ret) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
-            /* Skip over this much next time around */
-            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
-            buf->buf[0].pos += ret;
-            len -= ret;
 
-            /* Lets do another read */
-            continue;
-        }
         if (!ret) {
             /* EOF case? */
             fuse_log(FUSE_LOG_DEBUG, "%s: !ret len remaining=%zd\n", __func__,
                      len);
             break;
         }
+        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
+                 ret, len);
+
         len -= ret;
+        /* Short read. Retry reading remaining bytes */
+        if (len) {
+            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
+            /* Skip over this much next time around */
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
+            buf->buf[0].pos += ret;
+        }
     } while (len);
 
     /* Need to fix out->len on EOF */
-- 
2.25.4

[Virtio-fs] [PATCH v2 7/7] virtiofsd: Set req->reply_sent right after sending reply

[Vivek Goyal]

There is no reason to set it in label "err". We should be able to set
it right after sending reply. It is easier to read.

Also got rid of label "err" because now only thing it was doing was
return a code. We can return from the error location itself and no
need to first jump to label "err".

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 99f91c9d87..fa4aff9b0e 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -366,14 +366,12 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     if (in_len < sizeof(struct fuse_out_header)) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too short for out_header\n",
                  __func__, elem->index);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
     if (in_len < tosend_len) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n",
                  __func__, elem->index, tosend_len);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
 
     /* TODO: Limit to 'len' */
@@ -408,7 +406,7 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
             }
             fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n",
                      __func__, len);
-            goto err;
+            return ret;
         }
 
         if (!ret) {
@@ -438,21 +436,14 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         out_sg->len = tosend_len;
     }
 
-    ret = 0;
-
     vu_dispatch_rdlock(qi->virtio_dev);
     pthread_mutex_lock(&qi->vq_lock);
     vu_queue_push(dev, q, elem, tosend_len);
     vu_queue_notify(dev, q);
     pthread_mutex_unlock(&qi->vq_lock);
     vu_dispatch_unlock(qi->virtio_dev);
-
-err:
-    if (ret == 0) {
-        req->reply_sent = true;
-    }
-
-    return ret;
+    req->reply_sent = true;
+    return 0;
 }
 
 static __thread bool clone_fs_called;
-- 
2.25.4

[PATCH v2 7/7] virtiofsd: Set req->reply_sent right after sending reply

[Vivek Goyal]

There is no reason to set it in label "err". We should be able to set
it right after sending reply. It is easier to read.

Also got rid of label "err" because now only thing it was doing was
return a code. We can return from the error location itself and no
need to first jump to label "err".

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 tools/virtiofsd/fuse_virtio.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 99f91c9d87..fa4aff9b0e 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -366,14 +366,12 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     if (in_len < sizeof(struct fuse_out_header)) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too short for out_header\n",
                  __func__, elem->index);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
     if (in_len < tosend_len) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n",
                  __func__, elem->index, tosend_len);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
 
     /* TODO: Limit to 'len' */
@@ -408,7 +406,7 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
             }
             fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n",
                      __func__, len);
-            goto err;
+            return ret;
         }
 
         if (!ret) {
@@ -438,21 +436,14 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         out_sg->len = tosend_len;
     }
 
-    ret = 0;
-
     vu_dispatch_rdlock(qi->virtio_dev);
     pthread_mutex_lock(&qi->vq_lock);
     vu_queue_push(dev, q, elem, tosend_len);
     vu_queue_notify(dev, q);
     pthread_mutex_unlock(&qi->vq_lock);
     vu_dispatch_unlock(qi->virtio_dev);
-
-err:
-    if (ret == 0) {
-        req->reply_sent = true;
-    }
-
-    return ret;
+    req->reply_sent = true;
+    return 0;
 }
 
 static __thread bool clone_fs_called;
-- 
2.25.4

[Virtio-fs] Regression: Docker in vms broken.

[Harry G. Coin]

Something changed in virtiofs, likely to do with overlay support? 

Docker in a vm with virtiofs as root running with kernel 
5.8.0-53-generic works normally.  However, later 5.8 versions and also
5.11 versions fail with:


May 18 22:00:07 nocsupport4 systemd[1]: docker.service: Scheduled
restart job, restart counter is at 2.
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.061661124-05:00" level=info msg="Starting up"
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.109655841-05:00" level=info msg="detected
127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf:
/run/systemd/resolve/resolv.conf"
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.253580688-05:00" level=info msg="parsed
scheme: \"unix\"" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.253663917-05:00" level=info msg="scheme
\"unix\" not registered, fallback to default scheme" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.253737208-05:00" level=info
msg="ccResolverWrapper: sending update to cc:
{[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.253777767-05:00" level=info msg="ClientConn
switching balancer to \"pick_first\"" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.272602278-05:00" level=info msg="parsed
scheme: \"unix\"" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.272713227-05:00" level=info msg="scheme
\"unix\" not registered, fallback to default scheme" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.272778900-05:00" level=info
msg="ccResolverWrapper: sending update to cc:
{[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.272816740-05:00" level=info msg="ClientConn
switching balancer to \"pick_first\"" module=grpc
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.367601799-05:00" level=error msg="failed to
mount overlay: invalid argument" storage-driver=overlay2
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.367792469-05:00" level=error
msg="[graphdriver] prior storage driver overlay2 failed: driver not
supported"
May 18 22:00:10 nocsupport4 dockerd[1104]:
time="2021-05-18T22:00:10.370914131-05:00" level=info msg="stopping
event stream following graceful shutdown" error="context canceled"
module=libcontainerd namespace=plugins.moby
May 18 22:00:10 nocsupport4 dockerd[1104]: failed to start daemon: error
initializing graphdriver: driver not supported
May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Main process
exited, code=exited, status=1/FAILURE
May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Failed with
result 'exit-code'.

root@nocsupport4:~# cat /etc/fstab
myfs / virtiofs defaults 0 0

On the host:

root@noc4:/vmsystems# uname -a
Linux noc4.xxxx 5.11.0-17-generic

root      225434  0.0  0.0  80068  3544 ?        Sl   21:32   0:00
/usr/lib/qemu/virtiofsd --fd=32 -o
source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
libvirt+  225458 85.5  0.7 4366196 236724 ?      Sl   21:32   7:34
/usr/bin/qemu-system-x86_64 -name guest=nocsupport4,debug-threads=on -S
-object
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-6-nocsupport4/master-key.aes
-machine pc-q35-5.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off
-cpu
Conroe,vme=on,vmx=on,cx16=on,pdcm=on,x2apic=on,tsc-deadline=on,hypervisor=on,arat=on,tsc-adjust=on,arch-capabilities=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
-m 3584 -overcommit mem-lock=off -smp 2,sockets=2,cores=1,threads=1
-object
memory-backend-file,id=ram-node0,mem-path=/dev/hugepages/libvirt/qemu/6-nocsupport4,share=yes,prealloc=yes,size=3758096384
-numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -uuid
c7b055aa-1874-4ba9-9302-26fad866e749 -no-user-config -nodefaults
-chardev socket,id=charmonitor,fd=32,server,nowait -mon
chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew
-global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global
ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on
-kernel /vmsystems/nocsupport4/boot/vmlinuz -initrd
/vmsystems/nocsupport4/boot/initrd.img -append rootfstype=virtiofs
root=myfs  rw -device
pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
-device
pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1
-device
pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2
-device
pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3
-device
pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4
-device
pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5
-device
pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6
-device
pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7
-device pcie-pci-bridge,id=pci.9,bus=pci.4,addr=0x0 -device
ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7 -device
ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pcie.0,multifunction=on,addr=0x1d
-device
ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pcie.0,addr=0x1d.0x1
-device
ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pcie.0,addr=0x1d.0x2
-device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -chardev
socket,id=chr-vu-fs0,path=/var/lib/libvirt/qemu/domain-6-nocsupport4/fs0-fs.sock
-device
vhost-user-fs-pci,chardev=chr-vu-fs0,queue-size=1024,tag=myfs,bus=pci.1,addr=0x0
-netdev tap,fd=46,id=hostnet0,vhost=on,vhostfd=47 -device
virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:30:4d:ca,bus=pci.2,addr=0x0
-chardev pty,id=charserial0 -device
isa-serial,chardev=charserial0,id=serial0 -chardev
socket,id=charchannel0,fd=48,server,nowait -device
virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
-chardev spicevmc,id=charchannel1,name=vdagent -device
virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0
-device usb-tablet,id=input0,bus=usb.0,port=1 -spice
port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on -device
qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
-device ich9-intel-hda,id=sound0,bus=pcie.0,addr=0x1b -device
hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device
i6300esb,id=watchdog0,bus=pci.9,addr=0x1 -watchdog-action reset -chardev
spicevmc,id=charredir0,name=usbredir -device
usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev
spicevmc,id=charredir1,name=usbredir -device
usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device
virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -object
rng-random,id=objrng0,filename=/dev/urandom -device
virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 -sandbox
on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny
-msg timestamp=on
root      225472 11.0  0.0 6889960 10848 ?       Sl   21:32   0:58
/usr/lib/qemu/virtiofsd --fd=32 -o
source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback

Re: [Virtio-fs] Regression: Docker in vms broken.

[Vivek Goyal]

On Wed, May 19, 2021 at 08:35:59AM -0500, Harry G. Coin wrote:
> Something changed in virtiofs, likely to do with overlay support? 

I am not aware of any change in virtiofs w.r.t overlay. Are there any
messages on VM serail console from guest kernel? 

Vivek

> 
> Docker in a vm with virtiofs as root running with kernel 
> 5.8.0-53-generic works normally.  However, later 5.8 versions and also
> 5.11 versions fail with:
> 
> 
> May 18 22:00:07 nocsupport4 systemd[1]: docker.service: Scheduled
> restart job, restart counter is at 2.
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.061661124-05:00" level=info msg="Starting up"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.109655841-05:00" level=info msg="detected
> 127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf:
> /run/systemd/resolve/resolv.conf"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253580688-05:00" level=info msg="parsed
> scheme: \"unix\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253663917-05:00" level=info msg="scheme
> \"unix\" not registered, fallback to default scheme" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253737208-05:00" level=info
> msg="ccResolverWrapper: sending update to cc:
> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
> module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253777767-05:00" level=info msg="ClientConn
> switching balancer to \"pick_first\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272602278-05:00" level=info msg="parsed
> scheme: \"unix\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272713227-05:00" level=info msg="scheme
> \"unix\" not registered, fallback to default scheme" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272778900-05:00" level=info
> msg="ccResolverWrapper: sending update to cc:
> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
> module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272816740-05:00" level=info msg="ClientConn
> switching balancer to \"pick_first\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.367601799-05:00" level=error msg="failed to
> mount overlay: invalid argument" storage-driver=overlay2
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.367792469-05:00" level=error
> msg="[graphdriver] prior storage driver overlay2 failed: driver not
> supported"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.370914131-05:00" level=info msg="stopping
> event stream following graceful shutdown" error="context canceled"
> module=libcontainerd namespace=plugins.moby
> May 18 22:00:10 nocsupport4 dockerd[1104]: failed to start daemon: error
> initializing graphdriver: driver not supported
> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Main process
> exited, code=exited, status=1/FAILURE
> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Failed with
> result 'exit-code'.
> 
> root@nocsupport4:~# cat /etc/fstab
> myfs / virtiofs defaults 0 0
> 
> On the host:
> 
> root@noc4:/vmsystems# uname -a
> Linux noc4.xxxx 5.11.0-17-generic
> 
> root      225434  0.0  0.0  80068  3544 ?        Sl   21:32   0:00
> /usr/lib/qemu/virtiofsd --fd=32 -o
> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
> libvirt+  225458 85.5  0.7 4366196 236724 ?      Sl   21:32   7:34
> /usr/bin/qemu-system-x86_64 -name guest=nocsupport4,debug-threads=on -S
> -object
> secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-6-nocsupport4/master-key.aes
> -machine pc-q35-5.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off
> -cpu
> Conroe,vme=on,vmx=on,cx16=on,pdcm=on,x2apic=on,tsc-deadline=on,hypervisor=on,arat=on,tsc-adjust=on,arch-capabilities=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
> -m 3584 -overcommit mem-lock=off -smp 2,sockets=2,cores=1,threads=1
> -object
> memory-backend-file,id=ram-node0,mem-path=/dev/hugepages/libvirt/qemu/6-nocsupport4,share=yes,prealloc=yes,size=3758096384
> -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -uuid
> c7b055aa-1874-4ba9-9302-26fad866e749 -no-user-config -nodefaults
> -chardev socket,id=charmonitor,fd=32,server,nowait -mon
> chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew
> -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global
> ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on
> -kernel /vmsystems/nocsupport4/boot/vmlinuz -initrd
> /vmsystems/nocsupport4/boot/initrd.img -append rootfstype=virtiofs
> root=myfs  rw -device
> pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
> -device
> pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1
> -device
> pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2
> -device
> pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3
> -device
> pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4
> -device
> pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5
> -device
> pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6
> -device
> pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7
> -device pcie-pci-bridge,id=pci.9,bus=pci.4,addr=0x0 -device
> ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7 -device
> ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pcie.0,multifunction=on,addr=0x1d
> -device
> ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pcie.0,addr=0x1d.0x1
> -device
> ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pcie.0,addr=0x1d.0x2
> -device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -chardev
> socket,id=chr-vu-fs0,path=/var/lib/libvirt/qemu/domain-6-nocsupport4/fs0-fs.sock
> -device
> vhost-user-fs-pci,chardev=chr-vu-fs0,queue-size=1024,tag=myfs,bus=pci.1,addr=0x0
> -netdev tap,fd=46,id=hostnet0,vhost=on,vhostfd=47 -device
> virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:30:4d:ca,bus=pci.2,addr=0x0
> -chardev pty,id=charserial0 -device
> isa-serial,chardev=charserial0,id=serial0 -chardev
> socket,id=charchannel0,fd=48,server,nowait -device
> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
> -chardev spicevmc,id=charchannel1,name=vdagent -device
> virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0
> -device usb-tablet,id=input0,bus=usb.0,port=1 -spice
> port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on -device
> qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
> -device ich9-intel-hda,id=sound0,bus=pcie.0,addr=0x1b -device
> hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device
> i6300esb,id=watchdog0,bus=pci.9,addr=0x1 -watchdog-action reset -chardev
> spicevmc,id=charredir0,name=usbredir -device
> usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev
> spicevmc,id=charredir1,name=usbredir -device
> usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device
> virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -object
> rng-random,id=objrng0,filename=/dev/urandom -device
> virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 -sandbox
> on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny
> -msg timestamp=on
> root      225472 11.0  0.0 6889960 10848 ?       Sl   21:32   0:58
> /usr/lib/qemu/virtiofsd --fd=32 -o
> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
> 
> 
> 
> 
> 
> 
> _______________________________________________
> Virtio-fs mailing list
> Virtio-fs@redhat.com
> https://listman.redhat.com/mailman/listinfo/virtio-fs

Re: [Virtio-fs] Regression: Docker in vms broken.

[Dr. David Alan Gilbert]

* Harry G. Coin (hgcoin@gmail.com) wrote:
> Something changed in virtiofs, likely to do with overlay support? 

Hmm I don't think we have any explicit support in for overlayfs though.

> Docker in a vm with virtiofs as root running with kernel 
> 5.8.0-53-generic works normally.  However, later 5.8 versions and also
> 5.11 versions fail with:

Hmm, so what's your last working & first failing version of 5.8 ?

Dave

> 
> May 18 22:00:07 nocsupport4 systemd[1]: docker.service: Scheduled
> restart job, restart counter is at 2.
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.061661124-05:00" level=info msg="Starting up"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.109655841-05:00" level=info msg="detected
> 127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf:
> /run/systemd/resolve/resolv.conf"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253580688-05:00" level=info msg="parsed
> scheme: \"unix\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253663917-05:00" level=info msg="scheme
> \"unix\" not registered, fallback to default scheme" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253737208-05:00" level=info
> msg="ccResolverWrapper: sending update to cc:
> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
> module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.253777767-05:00" level=info msg="ClientConn
> switching balancer to \"pick_first\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272602278-05:00" level=info msg="parsed
> scheme: \"unix\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272713227-05:00" level=info msg="scheme
> \"unix\" not registered, fallback to default scheme" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272778900-05:00" level=info
> msg="ccResolverWrapper: sending update to cc:
> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
> module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.272816740-05:00" level=info msg="ClientConn
> switching balancer to \"pick_first\"" module=grpc
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.367601799-05:00" level=error msg="failed to
> mount overlay: invalid argument" storage-driver=overlay2
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.367792469-05:00" level=error
> msg="[graphdriver] prior storage driver overlay2 failed: driver not
> supported"
> May 18 22:00:10 nocsupport4 dockerd[1104]:
> time="2021-05-18T22:00:10.370914131-05:00" level=info msg="stopping
> event stream following graceful shutdown" error="context canceled"
> module=libcontainerd namespace=plugins.moby
> May 18 22:00:10 nocsupport4 dockerd[1104]: failed to start daemon: error
> initializing graphdriver: driver not supported
> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Main process
> exited, code=exited, status=1/FAILURE
> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Failed with
> result 'exit-code'.
> 
> root@nocsupport4:~# cat /etc/fstab
> myfs / virtiofs defaults 0 0
> 
> On the host:
> 
> root@noc4:/vmsystems# uname -a
> Linux noc4.xxxx 5.11.0-17-generic
> 
> root      225434  0.0  0.0  80068  3544 ?        Sl   21:32   0:00
> /usr/lib/qemu/virtiofsd --fd=32 -o
> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
> libvirt+  225458 85.5  0.7 4366196 236724 ?      Sl   21:32   7:34
> /usr/bin/qemu-system-x86_64 -name guest=nocsupport4,debug-threads=on -S
> -object
> secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-6-nocsupport4/master-key.aes
> -machine pc-q35-5.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off
> -cpu
> Conroe,vme=on,vmx=on,cx16=on,pdcm=on,x2apic=on,tsc-deadline=on,hypervisor=on,arat=on,tsc-adjust=on,arch-capabilities=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
> -m 3584 -overcommit mem-lock=off -smp 2,sockets=2,cores=1,threads=1
> -object
> memory-backend-file,id=ram-node0,mem-path=/dev/hugepages/libvirt/qemu/6-nocsupport4,share=yes,prealloc=yes,size=3758096384
> -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -uuid
> c7b055aa-1874-4ba9-9302-26fad866e749 -no-user-config -nodefaults
> -chardev socket,id=charmonitor,fd=32,server,nowait -mon
> chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew
> -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global
> ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on
> -kernel /vmsystems/nocsupport4/boot/vmlinuz -initrd
> /vmsystems/nocsupport4/boot/initrd.img -append rootfstype=virtiofs
> root=myfs  rw -device
> pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
> -device
> pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1
> -device
> pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2
> -device
> pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3
> -device
> pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4
> -device
> pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5
> -device
> pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6
> -device
> pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7
> -device pcie-pci-bridge,id=pci.9,bus=pci.4,addr=0x0 -device
> ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7 -device
> ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pcie.0,multifunction=on,addr=0x1d
> -device
> ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pcie.0,addr=0x1d.0x1
> -device
> ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pcie.0,addr=0x1d.0x2
> -device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -chardev
> socket,id=chr-vu-fs0,path=/var/lib/libvirt/qemu/domain-6-nocsupport4/fs0-fs.sock
> -device
> vhost-user-fs-pci,chardev=chr-vu-fs0,queue-size=1024,tag=myfs,bus=pci.1,addr=0x0
> -netdev tap,fd=46,id=hostnet0,vhost=on,vhostfd=47 -device
> virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:30:4d:ca,bus=pci.2,addr=0x0
> -chardev pty,id=charserial0 -device
> isa-serial,chardev=charserial0,id=serial0 -chardev
> socket,id=charchannel0,fd=48,server,nowait -device
> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
> -chardev spicevmc,id=charchannel1,name=vdagent -device
> virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0
> -device usb-tablet,id=input0,bus=usb.0,port=1 -spice
> port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on -device
> qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
> -device ich9-intel-hda,id=sound0,bus=pcie.0,addr=0x1b -device
> hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device
> i6300esb,id=watchdog0,bus=pci.9,addr=0x1 -watchdog-action reset -chardev
> spicevmc,id=charredir0,name=usbredir -device
> usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev
> spicevmc,id=charredir1,name=usbredir -device
> usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device
> virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -object
> rng-random,id=objrng0,filename=/dev/urandom -device
> virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 -sandbox
> on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny
> -msg timestamp=on
> root      225472 11.0  0.0 6889960 10848 ?       Sl   21:32   0:58
> /usr/lib/qemu/virtiofsd --fd=32 -o
> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
> 
> 
> 
> 
> 
> 
> _______________________________________________
> Virtio-fs mailing list
> Virtio-fs@redhat.com
> https://listman.redhat.com/mailman/listinfo/virtio-fs
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [Virtio-fs] Regression: Docker in vms broken.

[Harry G. Coin]

On 5/19/21 11:39 AM, Dr. David Alan Gilbert wrote:
> * Harry G. Coin (hgcoin@gmail.com) wrote:
>> Something changed in virtiofs, likely to do with overlay support? 
> Hmm I don't think we have any explicit support in for overlayfs though.
>
>> Docker in a vm with virtiofs as root running with kernel 
>> 5.8.0-53-generic works normally.  However, later 5.8 versions and also
>> 5.11 versions fail with:
> Hmm, so what's your last working & first failing version of 5.8 ?


I know that docker works in the VM (and has been for some months) with
guest and host running kernel 5.8.0-53-generic.  At least 3 docker
containers were running in the guest, and under conditions of heavy load
(ceph monitors, managers and filesystem gateways).   This was the case
on at least four similarly configured servers.  There is only ever one
guest vm accessing the underlying files on the hosts, and no contention
on the host for those files.  The FS on the host is btrfs, and xattr is
enabled on virtiofsd.  As the BAR on the pci device in mainline QEMU
hasn't made it into even bleeding-edge distros as yet, there is no dax. 
(And even after the pci bar makes it into qemu, I don't think dax will
find heavy adoption until it's also supported in libvirtd and virt-manager.)

root@noc3:~# /usr/lib/qemu/virtiofsd --version
using FUSE kernel interface version 7.31

When the *host*  updated to  5.11.0-17-generic (later virtiofsd), the
guest fails to run docker, erroring out as noted.

root@noc4:/vmsystems# /usr/lib/qemu/virtiofsd --version
using FUSE kernel interface version 7.32







> Dave
>
>> May 18 22:00:07 nocsupport4 systemd[1]: docker.service: Scheduled
>> restart job, restart counter is at 2.
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.061661124-05:00" level=info msg="Starting up"
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.109655841-05:00" level=info msg="detected
>> 127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf:
>> /run/systemd/resolve/resolv.conf"
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.253580688-05:00" level=info msg="parsed
>> scheme: \"unix\"" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.253663917-05:00" level=info msg="scheme
>> \"unix\" not registered, fallback to default scheme" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.253737208-05:00" level=info
>> msg="ccResolverWrapper: sending update to cc:
>> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
>> module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.253777767-05:00" level=info msg="ClientConn
>> switching balancer to \"pick_first\"" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.272602278-05:00" level=info msg="parsed
>> scheme: \"unix\"" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.272713227-05:00" level=info msg="scheme
>> \"unix\" not registered, fallback to default scheme" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.272778900-05:00" level=info
>> msg="ccResolverWrapper: sending update to cc:
>> {[{unix:///run/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}"
>> module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.272816740-05:00" level=info msg="ClientConn
>> switching balancer to \"pick_first\"" module=grpc
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.367601799-05:00" level=error msg="failed to
>> mount overlay: invalid argument" storage-driver=overlay2
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.367792469-05:00" level=error
>> msg="[graphdriver] prior storage driver overlay2 failed: driver not
>> supported"
>> May 18 22:00:10 nocsupport4 dockerd[1104]:
>> time="2021-05-18T22:00:10.370914131-05:00" level=info msg="stopping
>> event stream following graceful shutdown" error="context canceled"
>> module=libcontainerd namespace=plugins.moby
>> May 18 22:00:10 nocsupport4 dockerd[1104]: failed to start daemon: error
>> initializing graphdriver: driver not supported
>> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Main process
>> exited, code=exited, status=1/FAILURE
>> May 18 22:00:10 nocsupport4 systemd[1]: docker.service: Failed with
>> result 'exit-code'.
>>
>> root@nocsupport4:~# cat /etc/fstab
>> myfs / virtiofs defaults 0 0
>>
>> On the host:
>>
>> root@noc4:/vmsystems# uname -a
>> Linux noc4.xxxx 5.11.0-17-generic
>>
>> root      225434  0.0  0.0  80068  3544 ?        Sl   21:32   0:00
>> /usr/lib/qemu/virtiofsd --fd=32 -o
>> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
>> libvirt+  225458 85.5  0.7 4366196 236724 ?      Sl   21:32   7:34
>> /usr/bin/qemu-system-x86_64 -name guest=nocsupport4,debug-threads=on -S
>> -object
>> secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-6-nocsupport4/master-key.aes
>> -machine pc-q35-5.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off
>> -cpu
>> Conroe,vme=on,vmx=on,cx16=on,pdcm=on,x2apic=on,tsc-deadline=on,hypervisor=on,arat=on,tsc-adjust=on,arch-capabilities=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
>> -m 3584 -overcommit mem-lock=off -smp 2,sockets=2,cores=1,threads=1
>> -object
>> memory-backend-file,id=ram-node0,mem-path=/dev/hugepages/libvirt/qemu/6-nocsupport4,share=yes,prealloc=yes,size=3758096384
>> -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -uuid
>> c7b055aa-1874-4ba9-9302-26fad866e749 -no-user-config -nodefaults
>> -chardev socket,id=charmonitor,fd=32,server,nowait -mon
>> chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew
>> -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -global
>> ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on
>> -kernel /vmsystems/nocsupport4/boot/vmlinuz -initrd
>> /vmsystems/nocsupport4/boot/initrd.img -append rootfstype=virtiofs
>> root=myfs  rw -device
>> pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
>> -device
>> pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1
>> -device
>> pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2
>> -device
>> pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3
>> -device
>> pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4
>> -device
>> pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5
>> -device
>> pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6
>> -device
>> pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7
>> -device pcie-pci-bridge,id=pci.9,bus=pci.4,addr=0x0 -device
>> ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7 -device
>> ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pcie.0,multifunction=on,addr=0x1d
>> -device
>> ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pcie.0,addr=0x1d.0x1
>> -device
>> ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pcie.0,addr=0x1d.0x2
>> -device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -chardev
>> socket,id=chr-vu-fs0,path=/var/lib/libvirt/qemu/domain-6-nocsupport4/fs0-fs.sock
>> -device
>> vhost-user-fs-pci,chardev=chr-vu-fs0,queue-size=1024,tag=myfs,bus=pci.1,addr=0x0
>> -netdev tap,fd=46,id=hostnet0,vhost=on,vhostfd=47 -device
>> virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:30:4d:ca,bus=pci.2,addr=0x0
>> -chardev pty,id=charserial0 -device
>> isa-serial,chardev=charserial0,id=serial0 -chardev
>> socket,id=charchannel0,fd=48,server,nowait -device
>> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
>> -chardev spicevmc,id=charchannel1,name=vdagent -device
>> virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0
>> -device usb-tablet,id=input0,bus=usb.0,port=1 -spice
>> port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on -device
>> qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
>> -device ich9-intel-hda,id=sound0,bus=pcie.0,addr=0x1b -device
>> hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device
>> i6300esb,id=watchdog0,bus=pci.9,addr=0x1 -watchdog-action reset -chardev
>> spicevmc,id=charredir0,name=usbredir -device
>> usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=2 -chardev
>> spicevmc,id=charredir1,name=usbredir -device
>> usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=3 -device
>> virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -object
>> rng-random,id=objrng0,filename=/dev/urandom -device
>> virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 -sandbox
>> on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny
>> -msg timestamp=on
>> root      225472 11.0  0.0 6889960 10848 ?       Sl   21:32   0:58
>> /usr/lib/qemu/virtiofsd --fd=32 -o
>> source=/vmsystems/nocsupport4,xattr,flock,no_posix_lock -o writeback
>>
>>
>>
>>
>>
>>
>> _______________________________________________
>> Virtio-fs mailing list
>> Virtio-fs@redhat.com
>> https://listman.redhat.com/mailman/listinfo/virtio-fs

Re: [Virtio-fs] [PATCH v2 0/7] virtiofsd: Few cleanups in virtio_send_data_iov()

[Dr. David Alan Gilbert]

* Vivek Goyal (vgoyal@redhat.com) wrote:
> Hi,
> 
> This is V2 of the patches. Changes since V1 are.
> 
> - Took care of coding style issue.
> - Got rid of label "err" completely in last patch. (Dave, Connor). 
> - Captured Reviewed-by tags from Connor and David.
> 
> Code in virtio_send_data_iov() little twisted and complicated. This
> patch series just tries to simplify it a bit to make it little easier
> to read this piece of code.

Queued

> Thanks
> Vivek
> 
> 
> Vivek Goyal (7):
>   virtiofsd: Check for EINTR in preadv() and retry
>   virtiofsd: Get rid of unreachable code in read
>   virtiofsd: Use iov_discard_front() to skip bytes
>   virtiofsd: get rid of in_sg_left variable
>   virtiofsd: Simplify skip byte logic
>   virtiofsd: Check EOF before short read
>   virtiofsd: Set req->reply_sent right after sending reply
> 
>  tools/virtiofsd/fuse_virtio.c | 81 +++++++++++------------------------
>  1 file changed, 25 insertions(+), 56 deletions(-)
> 
> -- 
> 2.25.4
> 
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [PATCH v2 0/7] virtiofsd: Few cleanups in virtio_send_data_iov()

[Dr. David Alan Gilbert]

* Vivek Goyal (vgoyal@redhat.com) wrote:
> Hi,
> 
> This is V2 of the patches. Changes since V1 are.
> 
> - Took care of coding style issue.
> - Got rid of label "err" completely in last patch. (Dave, Connor). 
> - Captured Reviewed-by tags from Connor and David.
> 
> Code in virtio_send_data_iov() little twisted and complicated. This
> patch series just tries to simplify it a bit to make it little easier
> to read this piece of code.

Queued

> Thanks
> Vivek
> 
> 
> Vivek Goyal (7):
>   virtiofsd: Check for EINTR in preadv() and retry
>   virtiofsd: Get rid of unreachable code in read
>   virtiofsd: Use iov_discard_front() to skip bytes
>   virtiofsd: get rid of in_sg_left variable
>   virtiofsd: Simplify skip byte logic
>   virtiofsd: Check EOF before short read
>   virtiofsd: Set req->reply_sent right after sending reply
> 
>  tools/virtiofsd/fuse_virtio.c | 81 +++++++++++------------------------
>  1 file changed, 25 insertions(+), 56 deletions(-)
> 
> -- 
> 2.25.4
> 
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK