afs: Fix order-1 allocation in afs_do_lookup()

afs_do_lookup() will do an order-1 allocation to allocate status records if
there are more than 39 vnodes to stat.

Fix this by allocating an array of {status,callback} records for each vnode
we want to examine using vmalloc() if larger than a page.

This not only gets rid of the order-1 allocation, but makes it easier to
grow beyond 50 records for YFS servers.  It also allows us to move to
{status,callback} tuples for other calls too and makes it easier to lock
across the application of the status and the callback to the vnode.

Fixes: 5cf9dd55a0ec ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>

5 files changed, 45 insertions, 50 deletions

diff --git a/fs/afs/afs.h b/fs/afs/afs.h
index 74913c707bba..8fa0dffff1cc 100644
--- a/fs/afs/afs.h
+++ b/fs/afs/afs.h
@@ -147,6 +147,12 @@ struct afs_file_status {
         u32                     abort_code;     /* Abort if bulk-fetching this failed */
 };
 
+struct afs_status_cb {
+        struct afs_file_status  status;
+        struct afs_callback     callback;
+        bool                    have_cb;        /* True if cb record was retrieved */
+};
+
 /*
  * AFS file status change request
  */
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index c15550310f62..0f14bcfe233d 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -102,8 +102,7 @@ struct afs_lookup_cookie {
         bool                    found;
         bool                    one_only;
         unsigned short          nr_fids;
-        struct afs_file_status  *statuses;
-        struct afs_callback     *callbacks;
+        struct afs_status_cb    *statuses;
         struct afs_fid          fids[50];
 };
 
@@ -640,6 +639,7 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
         struct afs_lookup_cookie *cookie;
         struct afs_cb_interest *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_fs_cursor fc;
         struct afs_vnode *dvnode = AFS_FS_I(dir);
@@ -686,16 +686,11 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
 
         /* Need space for examining all the selected files */
         inode = ERR_PTR(-ENOMEM);
-        cookie->statuses = kcalloc(cookie->nr_fids, sizeof(struct afs_file_status),
-                                   GFP_KERNEL);
+        cookie->statuses = kvcalloc(cookie->nr_fids, sizeof(struct afs_status_cb),
+                                    GFP_KERNEL);
         if (!cookie->statuses)
                 goto out;
 
-        cookie->callbacks = kcalloc(cookie->nr_fids, sizeof(struct afs_callback),
-                                    GFP_KERNEL);
-        if (!cookie->callbacks)
-                goto out_s;
-
         /* Try FS.InlineBulkStatus first.  Abort codes for the individual
          * lookups contained therein are stored in the reply without aborting
          * the whole operation.
@@ -716,7 +711,6 @@ static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
                                                   afs_v2net(dvnode),
                                                   cookie->fids,
                                                   cookie->statuses,
-                                                  cookie->callbacks,
                                                   cookie->nr_fids, NULL);
                 }
 
@@ -741,11 +735,12 @@ no_inline_bulk_status:
         inode = ERR_PTR(-ERESTARTSYS);
         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
                 while (afs_select_fileserver(&fc)) {
+                        scb = &cookie->statuses[0];
                         afs_fs_fetch_status(&fc,
                                             afs_v2net(dvnode),
                                             cookie->fids,
-                                            cookie->statuses,
-                                            cookie->callbacks,
+                                            &scb->status,
+                                            &scb->callback,
                                             NULL);
                 }
 
@@ -758,24 +753,26 @@ no_inline_bulk_status:
                 goto out_c;
 
         for (i = 0; i < cookie->nr_fids; i++)
-                cookie->statuses[i].abort_code = 0;
+                cookie->statuses[i].status.abort_code = 0;
 
 success:
         /* Turn all the files into inodes and save the first one - which is the
          * one we actually want.
          */
-        if (cookie->statuses[0].abort_code != 0)
-                inode = ERR_PTR(afs_abort_to_error(cookie->statuses[0].abort_code));
+        scb = &cookie->statuses[0];
+        if (scb->status.abort_code != 0)
+                inode = ERR_PTR(afs_abort_to_error(scb->status.abort_code));
 
         for (i = 0; i < cookie->nr_fids; i++) {
+                struct afs_status_cb *scb = &cookie->statuses[i];
                 struct inode *ti;
 
-                if (cookie->statuses[i].abort_code != 0)
+                if (scb->status.abort_code != 0)
                         continue;
 
                 ti = afs_iget(dir->i_sb, key, &cookie->fids[i],
-                              &cookie->statuses[i],
-                              &cookie->callbacks[i],
+                              &scb->status,
+                              &scb->callback,
                               cbi, dvnode);
                 if (i == 0) {
                         inode = ti;
@@ -787,9 +784,7 @@ success:
 
 out_c:
         afs_put_cb_interest(afs_v2net(dvnode), cbi);
-        kfree(cookie->callbacks);
-out_s:
-        kfree(cookie->statuses);
+        kvfree(cookie->statuses);
 out:
         kfree(cookie);
         return inode;
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 16bcc578e3b2..eeba2a359fb4 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -2209,8 +2209,7 @@ int afs_fs_fetch_status(struct afs_fs_cursor *fc,
  */
 static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
 {
-        struct afs_file_status *statuses;
-        struct afs_callback *callbacks;
+        struct afs_status_cb *scb;
         const __be32 *bp;
         u32 tmp;
         int ret;
@@ -2249,8 +2248,8 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
                         return ret;
 
                 bp = call->buffer;
-                statuses = call->out_extra_status;
-                ret = afs_decode_status(call, &bp, &statuses[call->count],
+                scb = &call->out_scb[call->count];
+                ret = afs_decode_status(call, &bp, &scb->status,
                                         NULL, NULL, NULL);
                 if (ret < 0)
                         return ret;
@@ -2290,9 +2289,9 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
 
                 _debug("unmarshall CB array");
                 bp = call->buffer;
-                callbacks = call->out_cb;
-                xdr_decode_AFSCallBack_raw(call, &callbacks[call->count], &bp);
-                statuses = call->out_extra_status;
+                scb = &call->out_scb[call->count];
+                xdr_decode_AFSCallBack_raw(call, &scb->callback, &bp);
+                scb->have_cb = true;
                 call->count++;
                 if (call->count < call->count2)
                         goto more_cbs;
@@ -2335,8 +2334,7 @@ static const struct afs_call_type afs_RXFSInlineBulkStatus = {
 int afs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
                               struct afs_net *net,
                               struct afs_fid *fids,
-                              struct afs_file_status *statuses,
-                              struct afs_callback *callbacks,
+                              struct afs_status_cb *statuses,
                               unsigned int nr_fids,
                               struct afs_volsync *volsync)
 {
@@ -2345,7 +2343,7 @@ int afs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
         int i;
 
         if (test_bit(AFS_SERVER_FL_IS_YFS, &fc->cbi->server->flags))
-                return yfs_fs_inline_bulk_status(fc, net, fids, statuses, callbacks,
+                return yfs_fs_inline_bulk_status(fc, net, fids, statuses,
                                                  nr_fids, volsync);
 
         _enter(",%x,{%llx:%llu},%u",
@@ -2360,8 +2358,7 @@ int afs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
         }
 
         call->key = fc->key;
-        call->out_extra_status = statuses;
-        call->out_cb = callbacks;
+        call->out_scb = statuses;
         call->out_volsync = volsync;
         call->count2 = nr_fids;
         call->want_reply_time = true;
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 705833eb2d45..2a100be91721 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -137,6 +137,7 @@ struct afs_call {
         struct afs_file_status  *out_vnode_status;
         struct afs_file_status  *out_extra_status;
         struct afs_callback     *out_cb;
+        struct afs_status_cb    *out_scb;
         struct yfs_acl          *out_yacl;
         struct afs_volsync      *out_volsync;
         struct afs_volume_status *out_volstatus;
@@ -991,9 +992,8 @@ extern struct afs_call *afs_fs_get_capabilities(struct afs_net *, struct afs_ser
                                                 struct afs_addr_cursor *, struct key *,
                                                 unsigned int);
 extern int afs_fs_inline_bulk_status(struct afs_fs_cursor *, struct afs_net *,
-                                     struct afs_fid *, struct afs_file_status *,
-                                     struct afs_callback *, unsigned int,
-                                     struct afs_volsync *);
+                                     struct afs_fid *, struct afs_status_cb *,
+                                     unsigned int, struct afs_volsync *);
 extern int afs_fs_fetch_status(struct afs_fs_cursor *, struct afs_net *,
                                struct afs_fid *, struct afs_file_status *,
                                struct afs_callback *, struct afs_volsync *);
@@ -1393,9 +1393,8 @@ extern int yfs_fs_fetch_status(struct afs_fs_cursor *, struct afs_net *,
                                struct afs_fid *, struct afs_file_status *,
                                struct afs_callback *, struct afs_volsync *);
 extern int yfs_fs_inline_bulk_status(struct afs_fs_cursor *, struct afs_net *,
-                                     struct afs_fid *, struct afs_file_status *,
-                                     struct afs_callback *, unsigned int,
-                                     struct afs_volsync *);
+                                     struct afs_fid *, struct afs_status_cb *,
+                                     unsigned int, struct afs_volsync *);
 
 struct yfs_acl {
         struct afs_acl  *acl;           /* Dir/file/symlink ACL */
diff --git a/fs/afs/yfsclient.c b/fs/afs/yfsclient.c
index a815d22f62f1..1f1ccf7b7822 100644
--- a/fs/afs/yfsclient.c
+++ b/fs/afs/yfsclient.c
@@ -338,7 +338,7 @@ static void xdr_decode_YFSCallBack(struct afs_call *call,
         struct afs_callback cb;
 
         xdr_decode_YFSCallBack_raw(call, &cb, _bp);
-
+        
         write_seqlock(&vnode->cb_lock);
 
         if (!afs_cb_is_broken(call->cb_break, vnode, cbi)) {
@@ -2032,8 +2032,7 @@ int yfs_fs_fetch_status(struct afs_fs_cursor *fc,
  */
 static int yfs_deliver_fs_inline_bulk_status(struct afs_call *call)
 {
-        struct afs_file_status *statuses;
-        struct afs_callback *callbacks;
+        struct afs_status_cb *scb;
         const __be32 *bp;
         u32 tmp;
         int ret;
@@ -2072,8 +2071,8 @@ static int yfs_deliver_fs_inline_bulk_status(struct afs_call *call)
                         return ret;
 
                 bp = call->buffer;
-                statuses = call->out_extra_status;
-                ret = yfs_decode_status(call, &bp, &statuses[call->count],
+                scb = &call->out_scb[call->count];
+                ret = yfs_decode_status(call, &bp, &scb->status,
                                         NULL, NULL, NULL);
                 if (ret < 0)
                         return ret;
@@ -2113,8 +2112,9 @@ static int yfs_deliver_fs_inline_bulk_status(struct afs_call *call)
 
                 _debug("unmarshall CB array");
                 bp = call->buffer;
-                callbacks = call->out_cb;
-                xdr_decode_YFSCallBack_raw(call, &callbacks[call->count], &bp);
+                scb = &call->out_scb[call->count];
+                xdr_decode_YFSCallBack_raw(call, &scb->callback, &bp);
+                scb->have_cb = true;
                 call->count++;
                 if (call->count < call->count2)
                         goto more_cbs;
@@ -2158,8 +2158,7 @@ static const struct afs_call_type yfs_RXYFSInlineBulkStatus = {
 int yfs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
                               struct afs_net *net,
                               struct afs_fid *fids,
-                              struct afs_file_status *statuses,
-                              struct afs_callback *callbacks,
+                              struct afs_status_cb *statuses,
                               unsigned int nr_fids,
                               struct afs_volsync *volsync)
 {
@@ -2182,8 +2181,7 @@ int yfs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
         }
 
         call->key = fc->key;
-        call->out_extra_status = statuses;
-        call->out_cb = callbacks;
+        call->out_scb = statuses;
         call->out_volsync = volsync;
         call->count2 = nr_fids;