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[Qemu-devel] [PATCH 04/20] [V4] virtio-9p: readdir implementation for 9p
From: |
Venkateswararao Jujjuri (JV) |
Subject: |
[Qemu-devel] [PATCH 04/20] [V4] virtio-9p: readdir implementation for 9p2000.L |
Date: |
Mon, 28 Jun 2010 14:55:01 -0700 |
From: Sripathi Kodi <address@hidden>
This patch implements the server part of readdir() implementation for
9p2000.L
SYNOPSIS
size[4] Treaddir tag[2] fid[4] offset[8] count[4]
size[4] Rreaddir tag[2] count[4] data[count]
DESCRIPTION
The readdir request asks the server to read the directory specified by 'fid'
at an offset specified by 'offset' and return as many dirent structures as
possible that fit into count bytes. Each dirent structure is laid out as
follows.
qid.type[1]
the type of the file (directory, etc.), represented as a bit
vector corresponding to the high 8 bits of the file's mode
word.
qid.vers[4]
version number for given path
qid.path[8]
the file server's unique identification for the file
offset[8]
offset into the next dirent.
type[1]
type of this directory entry.
name[256]
name of this directory entry.
Signed-off-by: Sripathi Kodi <address@hidden>
Reviewed-by: M. Mohan Kumar <address@hidden>
Signed-off-by: Venkateswararao Jujjuri <address@hidden>
---
hw/virtio-9p-debug.c | 13 +++++
hw/virtio-9p.c | 122 ++++++++++++++++++++++++++++++++++++++++++++++++++
hw/virtio-9p.h | 2 +
3 files changed, 137 insertions(+), 0 deletions(-)
diff --git a/hw/virtio-9p-debug.c b/hw/virtio-9p-debug.c
index e4ab4bc..030b3e6 100644
--- a/hw/virtio-9p-debug.c
+++ b/hw/virtio-9p-debug.c
@@ -328,6 +328,19 @@ void pprint_pdu(V9fsPDU *pdu)
}
switch (pdu->id) {
+ case P9_TREADDIR:
+ fprintf(llogfile, "TREADDIR: (");
+ pprint_int32(pdu, 0, &offset, "fid");
+ pprint_int64(pdu, 0, &offset, ", initial offset");
+ pprint_int32(pdu, 0, &offset, ", max count");
+ break;
+ case P9_RREADDIR:
+ fprintf(llogfile, "RREADDIR: (");
+ pprint_int32(pdu, 1, &offset, "count");
+#ifdef DEBUG_DATA
+ pprint_data(pdu, 1, &offset, ", data");
+#endif
+ break;
case P9_TVERSION:
fprintf(llogfile, "TVERSION: (");
pprint_int32(pdu, 0, &offset, "msize");
diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c
index 0540a74..2918194 100644
--- a/hw/virtio-9p.c
+++ b/hw/virtio-9p.c
@@ -1577,6 +1577,127 @@ out:
qemu_free(vs);
}
+typedef struct V9fsReadDirState {
+ V9fsPDU *pdu;
+ V9fsFidState *fidp;
+ V9fsQID qid;
+ off_t saved_dir_pos;
+ struct dirent *dent;
+ int32_t count;
+ int32_t max_count;
+ size_t offset;
+ int64_t initial_offset;
+ V9fsString name;
+} V9fsReadDirState;
+
+static void v9fs_readdir_post_seekdir(V9fsState *s, V9fsReadDirState *vs)
+{
+ vs->offset += pdu_marshal(vs->pdu, vs->offset, "d", vs->count);
+ vs->offset += vs->count;
+ complete_pdu(s, vs->pdu, vs->offset);
+ qemu_free(vs);
+ return;
+}
+
+/* Size of each dirent on the wire: size of qid (13) + size of offset (8)
+ * size of type (1) + size of name.size (2) + strlen(name.data)
+ */
+#define V9_READDIR_DATA_SZ (24 + strlen(vs->name.data))
+
+static void v9fs_readdir_post_readdir(V9fsState *s, V9fsReadDirState *vs)
+{
+ int len;
+ size_t size;
+
+ if (vs->dent) {
+ v9fs_string_init(&vs->name);
+ v9fs_string_sprintf(&vs->name, "%s", vs->dent->d_name);
+
+ if ((vs->count + V9_READDIR_DATA_SZ) > vs->max_count) {
+ /* Ran out of buffer. Set dir back to old position and return */
+ v9fs_do_seekdir(s, vs->fidp->dir, vs->saved_dir_pos);
+ v9fs_readdir_post_seekdir(s, vs);
+ return;
+ }
+
+ /* Fill up just the path field of qid because the client uses
+ * only that. To fill the entire qid structure we will have
+ * to stat each dirent found, which is expensive
+ */
+ size = MIN(sizeof(vs->dent->d_ino), sizeof(vs->qid.path));
+ memcpy(&vs->qid.path, &vs->dent->d_ino, size);
+ /* Fill the other fields with dummy values */
+ vs->qid.type = 0;
+ vs->qid.version = 0;
+
+ len = pdu_marshal(vs->pdu, vs->offset+4+vs->count, "Qqbs",
+ &vs->qid, vs->dent->d_off,
+ vs->dent->d_type, &vs->name);
+ vs->count += len;
+ v9fs_string_free(&vs->name);
+ vs->saved_dir_pos = vs->dent->d_off;
+ vs->dent = v9fs_do_readdir(s, vs->fidp->dir);
+ v9fs_readdir_post_readdir(s, vs);
+ return;
+ }
+
+ vs->offset += pdu_marshal(vs->pdu, vs->offset, "d", vs->count);
+ vs->offset += vs->count;
+ complete_pdu(s, vs->pdu, vs->offset);
+ qemu_free(vs);
+ return;
+}
+
+static void v9fs_readdir_post_telldir(V9fsState *s, V9fsReadDirState *vs)
+{
+ vs->dent = v9fs_do_readdir(s, vs->fidp->dir);
+ v9fs_readdir_post_readdir(s, vs);
+ return;
+}
+
+static void v9fs_readdir_post_setdir(V9fsState *s, V9fsReadDirState *vs)
+{
+ vs->saved_dir_pos = v9fs_do_telldir(s, vs->fidp->dir);
+ v9fs_readdir_post_telldir(s, vs);
+ return;
+}
+
+static void v9fs_readdir(V9fsState *s, V9fsPDU *pdu)
+{
+ int32_t fid;
+ V9fsReadDirState *vs;
+ ssize_t err = 0;
+ size_t offset = 7;
+
+ vs = qemu_malloc(sizeof(*vs));
+ vs->pdu = pdu;
+ vs->offset = 7;
+ vs->count = 0;
+
+ pdu_unmarshal(vs->pdu, offset, "dqd", &fid, &vs->initial_offset,
+ &vs->max_count);
+
+ vs->fidp = lookup_fid(s, fid);
+ if (vs->fidp == NULL || !(vs->fidp->dir)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (vs->initial_offset == 0) {
+ v9fs_do_rewinddir(s, vs->fidp->dir);
+ } else {
+ v9fs_do_seekdir(s, vs->fidp->dir, vs->initial_offset);
+ }
+
+ v9fs_readdir_post_setdir(s, vs);
+ return;
+
+out:
+ complete_pdu(s, pdu, err);
+ qemu_free(vs);
+ return;
+}
+
static void v9fs_write_post_writev(V9fsState *s, V9fsWriteState *vs,
ssize_t err)
{
@@ -2211,6 +2332,7 @@ out:
typedef void (pdu_handler_t)(V9fsState *s, V9fsPDU *pdu);
static pdu_handler_t *pdu_handlers[] = {
+ [P9_TREADDIR] = v9fs_readdir,
[P9_TSTATFS] = v9fs_statfs,
[P9_TVERSION] = v9fs_version,
[P9_TATTACH] = v9fs_attach,
diff --git a/hw/virtio-9p.h b/hw/virtio-9p.h
index 992c765..9773659 100644
--- a/hw/virtio-9p.h
+++ b/hw/virtio-9p.h
@@ -15,6 +15,8 @@
enum {
P9_TSTATFS = 8,
P9_RSTATFS,
+ P9_TREADDIR = 40,
+ P9_RREADDIR,
P9_TVERSION = 100,
P9_RVERSION,
P9_TAUTH = 102,
--
1.6.5.2
- [Qemu-devel] [PATCH 01/20] qemu: virtio-9p: Recognize 9P2000.L protocol, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 07/20] virtio-9p: Do not reset atime, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 04/20] [V4] virtio-9p: readdir implementation for 9p2000.L,
Venkateswararao Jujjuri (JV) <=
- [Qemu-devel] [PATCH 09/20] virtio-9p: Implement server side of setattr for 9P2000.L protocol., Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 12/20] [virtio-9p] This patch implements TLCREATE for 9p2000.L protocol., Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 05/20] virtio-9p: Compute iounit based on host filesystem block size, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 18/20] virtio-9p: Implement TXATTRWALK, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 10/20] [virtio-9p] Implement TLINK for 9P2000.L, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 06/20] virtio-9p: getattr server implementation for 9P2000.L protocol., Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 17/20] virtio-9p: Add fidtype so that we can do type specific operation, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 03/20] virtio-9p: Return correct error from v9fs_remove, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 19/20] virtio-9p: Implement TXATTRCREATE, Venkateswararao Jujjuri (JV), 2010/06/28
- [Qemu-devel] [PATCH 16/20] qemu: virtio-9p: Implement LOPEN, Venkateswararao Jujjuri (JV), 2010/06/28