CIFS: Process oplocks for SMB2

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>

7 files changed, 68 insertions, 12 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 9adf211ca95a..3eb59ed6904a 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -328,6 +328,8 @@ struct smb_version_operations {
                          struct cifs_fid *);
         /* calculate a size of SMB message */
         unsigned int (*calc_smb_size)(void *);
+        /* check for STATUS_PENDING and process it in a positive case */
+        bool (*is_status_pending)(char *, struct TCP_Server_Info *, int);
 };
 
 struct smb_version_values {
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index c31b30b572e0..549409b1c776 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -819,6 +819,10 @@ standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
                 cifs_dump_mem("Bad SMB: ", buf,
                         min_t(unsigned int, server->total_read, 48));
 
+        if (server->ops->is_status_pending &&
+            server->ops->is_status_pending(buf, server, length))
+                return -1;
+
         if (!mid)
                 return length;
 
diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c
index a7618dfb7712..5ff25e025215 100644
--- a/fs/cifs/smb2file.c
+++ b/fs/cifs/smb2file.c
@@ -34,6 +34,26 @@
 #include "fscache.h"
 #include "smb2proto.h"
 
+void
+smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
+{
+        oplock &= 0xFF;
+        if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE) {
+                cinode->clientCanCacheAll = true;
+                cinode->clientCanCacheRead = true;
+                cFYI(1, "Exclusive Oplock granted on inode %p",
+                     &cinode->vfs_inode);
+        } else if (oplock == SMB2_OPLOCK_LEVEL_II) {
+                cinode->clientCanCacheAll = false;
+                cinode->clientCanCacheRead = true;
+                cFYI(1, "Level II Oplock granted on inode %p",
+                    &cinode->vfs_inode);
+        } else {
+                cinode->clientCanCacheAll = false;
+                cinode->clientCanCacheRead = false;
+        }
+}
+
 int
 smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path,
                int disposition, int desired_access, int create_options,
@@ -58,10 +78,11 @@ smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path,
         }
 
         desired_access |= FILE_READ_ATTRIBUTES;
+        *oplock = SMB2_OPLOCK_LEVEL_EXCLUSIVE;
 
         rc = SMB2_open(xid, tcon, smb2_path, &fid->persistent_fid,
                        &fid->volatile_fid, desired_access, disposition,
-                       0, 0, smb2_data);
+                       0, 0, (__u8 *)oplock, smb2_data);
         if (rc)
                 goto out;
 
@@ -79,7 +100,6 @@ smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path,
         }
 
 out:
-        *oplock = 0;
         kfree(smb2_data);
         kfree(smb2_path);
         return rc;
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index 1bd6b0f0c10e..706482452df4 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -47,6 +47,7 @@ smb2_open_op_close(const unsigned int xid, struct cifs_tcon *tcon,
         int rc, tmprc = 0;
         u64 persistent_fid, volatile_fid;
         __le16 *utf16_path;
+        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
 
         utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
         if (!utf16_path)
@@ -54,7 +55,7 @@ smb2_open_op_close(const unsigned int xid, struct cifs_tcon *tcon,
 
         rc = SMB2_open(xid, tcon, utf16_path, &persistent_fid, &volatile_fid,
                        desired_access, create_disposition, file_attributes,
-                       create_options, NULL);
+                       create_options, &oplock, NULL);
         if (rc) {
                 kfree(utf16_path);
                 return rc;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 0fa086c1b5dc..2d88c90ded0c 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -23,6 +23,7 @@
 #include "smb2proto.h"
 #include "cifsproto.h"
 #include "cifs_debug.h"
+#include "smb2status.h"
 
 static int
 change_conf(struct TCP_Server_Info *server)
@@ -207,13 +208,14 @@ smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
         int rc;
         __u64 persistent_fid, volatile_fid;
         __le16 *utf16_path;
+        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
 
         utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
         if (!utf16_path)
                 return -ENOMEM;
 
         rc = SMB2_open(xid, tcon, utf16_path, &persistent_fid, &volatile_fid,
-                       FILE_READ_ATTRIBUTES, FILE_OPEN, 0, 0, NULL);
+                       FILE_READ_ATTRIBUTES, FILE_OPEN, 0, 0, &oplock, NULL);
         if (rc) {
                 kfree(utf16_path);
                 return rc;
@@ -358,10 +360,10 @@ smb2_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
 static void
 smb2_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
 {
-        /* struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); */
+        struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
         cfile->fid.persistent_fid = fid->persistent_fid;
         cfile->fid.volatile_fid = fid->volatile_fid;
-        /* cifs_set_oplock_level(cinode, oplock); */
+        smb2_set_oplock_level(cinode, oplock);
         /* cinode->can_cache_brlcks = cinode->clientCanCacheAll; */
 }
 
@@ -432,6 +434,7 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
 {
         __le16 *utf16_path;
         int rc;
+        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
         __u64 persistent_fid, volatile_fid;
 
         utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
@@ -440,7 +443,7 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
 
         rc = SMB2_open(xid, tcon, utf16_path, &persistent_fid, &volatile_fid,
                        FILE_READ_ATTRIBUTES | FILE_READ_DATA, FILE_OPEN, 0, 0,
-                       NULL);
+                       &oplock, NULL);
         kfree(utf16_path);
         if (rc) {
                 cERROR(1, "open dir failed");
@@ -477,6 +480,28 @@ smb2_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
         return SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
 }
 
+/*
+* If we negotiate SMB2 protocol and get STATUS_PENDING - update
+* the number of credits and return true. Otherwise - return false.
+*/
+static bool
+smb2_is_status_pending(char *buf, struct TCP_Server_Info *server, int length)
+{
+        struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
+
+        if (le32_to_cpu(hdr->Status) != STATUS_PENDING)
+                return false;
+
+        if (!length) {
+                spin_lock(&server->req_lock);
+                server->credits += le16_to_cpu(hdr->CreditRequest);
+                spin_unlock(&server->req_lock);
+                wake_up(&server->request_q);
+        }
+
+        return true;
+}
+
 struct smb_version_operations smb21_operations = {
         .setup_request = smb2_setup_request,
         .setup_async_request = smb2_setup_async_request,
@@ -530,6 +555,7 @@ struct smb_version_operations smb21_operations = {
         .query_dir_next = smb2_query_dir_next,
         .close_dir = smb2_close_dir,
         .calc_smb_size = smb2_calc_size,
+        .is_status_pending = smb2_is_status_pending,
 };
 
 struct smb_version_values smb21_values = {
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 21b3a652e192..e97c256c8a42 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -872,7 +872,7 @@ int
 SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
           u64 *persistent_fid, u64 *volatile_fid, __u32 desired_access,
           __u32 create_disposition, __u32 file_attributes, __u32 create_options,
-          struct smb2_file_all_info *buf)
+          __u8 *oplock, struct smb2_file_all_info *buf)
 {
         struct smb2_create_req *req;
         struct smb2_create_rsp *rsp;
@@ -895,9 +895,9 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
         if (rc)
                 return rc;
 
-        /* if (server->oplocks)
-                req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_BATCH;
-        else */
+        if (server->oplocks)
+                req->RequestedOplockLevel = *oplock;
+        else
                 req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_NONE;
         req->ImpersonationLevel = IL_IMPERSONATION;
         req->DesiredAccess = cpu_to_le32(desired_access);
@@ -954,6 +954,8 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
                 buf->NumberOfLinks = cpu_to_le32(1);
                 buf->DeletePending = 0;
         }
+
+        *oplock = rsp->OplockLevel;
 creat_exit:
         free_rsp_buf(resp_buftype, rsp);
         return rc;
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 0d29db222a5a..d18339fcc8a2 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -82,6 +82,7 @@ extern int smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon,
                           int desired_access, int create_options,
                           struct cifs_fid *fid, __u32 *oplock,
                           FILE_ALL_INFO *buf, struct cifs_sb_info *cifs_sb);
+extern void smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock);
 
 /*
  * SMB2 Worker functions - most of protocol specific implementation details
@@ -99,7 +100,7 @@ extern int SMB2_open(const unsigned int xid, struct cifs_tcon *tcon,
                      __le16 *path, u64 *persistent_fid, u64 *volatile_fid,
                      __u32 desired_access, __u32 create_disposition,
                      __u32 file_attributes, __u32 create_options,
-                     struct smb2_file_all_info *buf);
+                     __u8 *oplock, struct smb2_file_all_info *buf);
 extern int SMB2_close(const unsigned int xid, struct cifs_tcon *tcon,
                       u64 persistent_file_id, u64 volatile_file_id);
 extern int SMB2_flush(const unsigned int xid, struct cifs_tcon *tcon,