afs: Pass pre-fetch server and volume break counts into afs_iget5_set()

Pass the server and volume break counts from before the status fetch
operation that queried the attributes of a file into afs_iget5_set() so
that the new vnode's break counters can be initialised appropriately.

This allows detection of a volume or server break that happened whilst we
were fetching the status or setting up the vnode.

Fixes: c435ee34551e ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>

4 files changed, 78 insertions, 49 deletions

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index d1b3736a3bbd..9e42f6c75747 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -641,7 +641,7 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
         struct afs_cb_interest *dcbi, *cbi = NULL;
         struct afs_super_info *as = dir->i_sb->s_fs_info;
         struct afs_status_cb *scb;
-        struct afs_iget_data data;
+        struct afs_iget_data iget_data;
         struct afs_fs_cursor fc;
         struct afs_server *server;
         struct afs_vnode *dvnode = AFS_FS_I(dir);
@@ -684,9 +684,12 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
                 goto out;
 
         /* Check to see if we already have an inode for the primary fid. */
-        data.volume = dvnode->volume;
-        data.fid = cookie->fids[0];
-        inode = ilookup5(dir->i_sb, cookie->fids[0].vnode, afs_iget5_test, &data);
+        iget_data.fid = cookie->fids[0];
+        iget_data.volume = dvnode->volume;
+        iget_data.cb_v_break = dvnode->volume->cb_v_break;
+        iget_data.cb_s_break = 0;
+        inode = ilookup5(dir->i_sb, cookie->fids[0].vnode,
+                         afs_iget5_test, &iget_data);
         if (inode)
                 goto out;
 
@@ -713,6 +716,8 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
                                 fc.ac.error = -ECONNABORTED;
                                 break;
                         }
+                        iget_data.cb_v_break = dvnode->volume->cb_v_break;
+                        iget_data.cb_s_break = fc.cbi->server->cb_s_break;
                         afs_fs_inline_bulk_status(&fc,
                                                   afs_v2net(dvnode),
                                                   cookie->fids,
@@ -741,6 +746,8 @@ no_inline_bulk_status:
         inode = ERR_PTR(-ERESTARTSYS);
         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
                 while (afs_select_fileserver(&fc)) {
+                        iget_data.cb_v_break = dvnode->volume->cb_v_break;
+                        iget_data.cb_s_break = fc.cbi->server->cb_s_break;
                         scb = &cookie->statuses[0];
                         afs_fs_fetch_status(&fc,
                                             afs_v2net(dvnode),
@@ -775,8 +782,8 @@ success:
                 if (scb->status.abort_code != 0)
                         continue;
 
-                ti = afs_iget(dir->i_sb, key, &cookie->fids[i],
-                              scb, cbi, dvnode);
+                iget_data.fid = cookie->fids[i];
+                ti = afs_iget(dir->i_sb, key, &iget_data, scb, cbi, dvnode);
                 if (i == 0) {
                         inode = ti;
                 } else {
@@ -1112,7 +1119,7 @@ void afs_d_release(struct dentry *dentry)
  */
 static void afs_vnode_new_inode(struct afs_fs_cursor *fc,
                                 struct dentry *new_dentry,
-                                struct afs_fid *newfid,
+                                struct afs_iget_data *new_data,
                                 struct afs_status_cb *new_scb)
 {
         struct afs_vnode *vnode;
@@ -1122,7 +1129,7 @@ static void afs_vnode_new_inode(struct afs_fs_cursor *fc,
                 return;
 
         inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key,
-                         newfid, new_scb, fc->cbi, fc->vnode);
+                         new_data, new_scb, fc->cbi, fc->vnode);
         if (IS_ERR(inode)) {
                 /* ENOMEM or EINTR at a really inconvenient time - just abandon
                  * the new directory on the server.
@@ -1138,15 +1145,23 @@ static void afs_vnode_new_inode(struct afs_fs_cursor *fc,
         d_instantiate(new_dentry, inode);
 }
 
+static void afs_prep_for_new_inode(struct afs_fs_cursor *fc,
+                                   struct afs_iget_data *iget_data)
+{
+        iget_data->volume = fc->vnode->volume;
+        iget_data->cb_v_break = fc->vnode->volume->cb_v_break;
+        iget_data->cb_s_break = fc->cbi->server->cb_s_break;
+}
+
 /*
  * create a directory on an AFS filesystem
  */
 static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
+        struct afs_iget_data iget_data;
         struct afs_status_cb *scb;
         struct afs_fs_cursor fc;
         struct afs_vnode *dvnode = AFS_FS_I(dir);
-        struct afs_fid newfid;
         struct key *key;
         int ret;
 
@@ -1172,14 +1187,15 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 
                 while (afs_select_fileserver(&fc)) {
                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
+                        afs_prep_for_new_inode(&fc, &iget_data);
                         afs_fs_create(&fc, dentry->d_name.name, mode,
-                                      &scb[0], &newfid, &scb[1]);
+                                      &scb[0], &iget_data.fid, &scb[1]);
                 }
 
                 afs_check_for_remote_deletion(&fc, dvnode);
                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
                                         &data_version, &scb[0]);
-                afs_vnode_new_inode(&fc, dentry, &newfid, &scb[1]);
+                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
                 ret = afs_end_vnode_operation(&fc);
                 if (ret < 0)
                         goto error_key;
@@ -1189,7 +1205,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 
         if (ret == 0 &&
             test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
-                afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
+                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
                                  afs_edit_dir_for_create);
 
         key_put(key);
@@ -1439,10 +1455,10 @@ error:
 static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
                       bool excl)
 {
+        struct afs_iget_data iget_data;
         struct afs_fs_cursor fc;
         struct afs_status_cb *scb;
         struct afs_vnode *dvnode = AFS_FS_I(dir);
-        struct afs_fid newfid;
         struct key *key;
         int ret;
 
@@ -1472,14 +1488,15 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 
                 while (afs_select_fileserver(&fc)) {
                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
+                        afs_prep_for_new_inode(&fc, &iget_data);
                         afs_fs_create(&fc, dentry->d_name.name, mode,
-                                      &scb[0], &newfid, &scb[1]);
+                                      &scb[0], &iget_data.fid, &scb[1]);
                 }
 
                 afs_check_for_remote_deletion(&fc, dvnode);
                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
                                         &data_version, &scb[0]);
-                afs_vnode_new_inode(&fc, dentry, &newfid, &scb[1]);
+                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
                 ret = afs_end_vnode_operation(&fc);
                 if (ret < 0)
                         goto error_key;
@@ -1488,7 +1505,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
         }
 
         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
-                afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
+                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
                                  afs_edit_dir_for_create);
 
         kfree(scb);
@@ -1595,10 +1612,10 @@ error:
 static int afs_symlink(struct inode *dir, struct dentry *dentry,
                        const char *content)
 {
+        struct afs_iget_data iget_data;
         struct afs_fs_cursor fc;
         struct afs_status_cb *scb;
         struct afs_vnode *dvnode = AFS_FS_I(dir);
-        struct afs_fid newfid;
         struct key *key;
         int ret;
 
@@ -1631,14 +1648,15 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
 
                 while (afs_select_fileserver(&fc)) {
                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
+                        afs_prep_for_new_inode(&fc, &iget_data);
                         afs_fs_symlink(&fc, dentry->d_name.name, content,
-                                       &scb[0], &newfid, &scb[1]);
+                                       &scb[0], &iget_data.fid, &scb[1]);
                 }
 
                 afs_check_for_remote_deletion(&fc, dvnode);
                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
                                         &data_version, &scb[0]);
-                afs_vnode_new_inode(&fc, dentry, &newfid, &scb[1]);
+                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
                 ret = afs_end_vnode_operation(&fc);
                 if (ret < 0)
                         goto error_key;
@@ -1647,7 +1665,7 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
         }
 
         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
-                afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
+                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
                                  afs_edit_dir_for_symlink);
 
         key_put(key);
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index e1a523d2e378..b42d9d09669c 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -347,10 +347,10 @@ int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
  */
 int afs_iget5_test(struct inode *inode, void *opaque)
 {
-        struct afs_iget_data *data = opaque;
+        struct afs_iget_data *iget_data = opaque;
         struct afs_vnode *vnode = AFS_FS_I(inode);
 
-        return memcmp(&vnode->fid, &data->fid, sizeof(data->fid)) == 0;
+        return memcmp(&vnode->fid, &iget_data->fid, sizeof(iget_data->fid)) == 0;
 }
 
 /*
@@ -368,17 +368,19 @@ static int afs_iget5_pseudo_dir_test(struct inode *inode, void *opaque)
  */
 static int afs_iget5_set(struct inode *inode, void *opaque)
 {
-        struct afs_iget_data *data = opaque;
+        struct afs_iget_data *iget_data = opaque;
         struct afs_vnode *vnode = AFS_FS_I(inode);
 
-        vnode->fid = data->fid;
-        vnode->volume = data->volume;
+        vnode->fid              = iget_data->fid;
+        vnode->volume           = iget_data->volume;
+        vnode->cb_v_break       = iget_data->cb_v_break;
+        vnode->cb_s_break       = iget_data->cb_s_break;
 
         /* YFS supports 96-bit vnode IDs, but Linux only supports
          * 64-bit inode numbers.
          */
-        inode->i_ino = data->fid.vnode;
-        inode->i_generation = data->fid.unique;
+        inode->i_ino            = iget_data->fid.vnode;
+        inode->i_generation     = iget_data->fid.unique;
         return 0;
 }
 
@@ -388,38 +390,42 @@ static int afs_iget5_set(struct inode *inode, void *opaque)
  */
 struct inode *afs_iget_pseudo_dir(struct super_block *sb, bool root)
 {
-        struct afs_iget_data data;
         struct afs_super_info *as;
         struct afs_vnode *vnode;
         struct inode *inode;
         static atomic_t afs_autocell_ino;
 
+        struct afs_iget_data iget_data = {
+                .cb_v_break = 0,
+                .cb_s_break = 0,
+        };
+
         _enter("");
 
         as = sb->s_fs_info;
         if (as->volume) {
-                data.volume = as->volume;
-                data.fid.vid = as->volume->vid;
+                iget_data.volume = as->volume;
+                iget_data.fid.vid = as->volume->vid;
         }
         if (root) {
-                data.fid.vnode = 1;
-                data.fid.unique = 1;
+                iget_data.fid.vnode = 1;
+                iget_data.fid.unique = 1;
         } else {
-                data.fid.vnode = atomic_inc_return(&afs_autocell_ino);
-                data.fid.unique = 0;
+                iget_data.fid.vnode = atomic_inc_return(&afs_autocell_ino);
+                iget_data.fid.unique = 0;
         }
 
-        inode = iget5_locked(sb, data.fid.vnode,
+        inode = iget5_locked(sb, iget_data.fid.vnode,
                              afs_iget5_pseudo_dir_test, afs_iget5_set,
-                             &data);
+                             &iget_data);
         if (!inode) {
                 _leave(" = -ENOMEM");
                 return ERR_PTR(-ENOMEM);
         }
 
         _debug("GOT INODE %p { ino=%lu, vl=%llx, vn=%llx, u=%x }",
-               inode, inode->i_ino, data.fid.vid, data.fid.vnode,
-               data.fid.unique);
+               inode, inode->i_ino, iget_data.fid.vid, iget_data.fid.vnode,
+               iget_data.fid.unique);
 
         vnode = AFS_FS_I(inode);
 
@@ -490,23 +496,24 @@ static void afs_get_inode_cache(struct afs_vnode *vnode)
  * inode retrieval
  */
 struct inode *afs_iget(struct super_block *sb, struct key *key,
-                       struct afs_fid *fid, struct afs_status_cb *scb,
+                       struct afs_iget_data *iget_data,
+                       struct afs_status_cb *scb,
                        struct afs_cb_interest *cbi,
                        struct afs_vnode *parent_vnode)
 {
-        struct afs_iget_data data = { .fid = *fid };
         struct afs_super_info *as;
         struct afs_vnode *vnode;
+        struct afs_fid *fid = &iget_data->fid;
         struct inode *inode;
         int ret;
 
         _enter(",{%llx:%llu.%u},,", fid->vid, fid->vnode, fid->unique);
 
         as = sb->s_fs_info;
-        data.volume = as->volume;
+        iget_data->volume = as->volume;
 
         inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
-                             &data);
+                             iget_data);
         if (!inode) {
                 _leave(" = -ENOMEM");
                 return ERR_PTR(-ENOMEM);
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index f80ca638e70f..2073c1a3ab4b 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -66,6 +66,8 @@ struct afs_fs_context {
 struct afs_iget_data {
         struct afs_fid          fid;
         struct afs_volume       *volume;        /* volume on which resides */
+        unsigned int            cb_v_break;     /* Pre-fetch volume break count */
+        unsigned int            cb_s_break;     /* Pre-fetch server break count */
 };
 
 enum afs_call_state {
@@ -1023,7 +1025,7 @@ extern int afs_fetch_status(struct afs_vnode *, struct key *, bool, afs_access_t
 extern int afs_iget5_test(struct inode *, void *);
 extern struct inode *afs_iget_pseudo_dir(struct super_block *, bool);
 extern struct inode *afs_iget(struct super_block *, struct key *,
-                              struct afs_fid *, struct afs_status_cb *,
+                              struct afs_iget_data *, struct afs_status_cb *,
                               struct afs_cb_interest *,
                               struct afs_vnode *);
 extern void afs_zap_data(struct afs_vnode *);
diff --git a/fs/afs/super.c b/fs/afs/super.c
index f76473ad7bbb..f18911e8d770 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -426,7 +426,7 @@ static int afs_set_super(struct super_block *sb, struct fs_context *fc)
 static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
 {
         struct afs_super_info *as = AFS_FS_S(sb);
-        struct afs_fid fid;
+        struct afs_iget_data iget_data;
         struct inode *inode = NULL;
         int ret;
 
@@ -451,11 +451,13 @@ static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
         } else {
                 sprintf(sb->s_id, "%llu", as->volume->vid);
                 afs_activate_volume(as->volume);
-                fid.vid         = as->volume->vid;
-                fid.vnode       = 1;
-                fid.vnode_hi    = 0;
-                fid.unique      = 1;
-                inode = afs_iget(sb, ctx->key, &fid, NULL, NULL, NULL);
+                iget_data.fid.vid       = as->volume->vid;
+                iget_data.fid.vnode     = 1;
+                iget_data.fid.vnode_hi  = 0;
+                iget_data.fid.unique    = 1;
+                iget_data.cb_v_break    = as->volume->cb_v_break;
+                iget_data.cb_s_break    = 0;
+                inode = afs_iget(sb, ctx->key, &iget_data, NULL, NULL, NULL);
         }
 
         if (IS_ERR(inode))