5 files changed, 103 insertions, 11 deletions

diff --git a/fs/cifs/CHANGES b/fs/cifs/CHANGES
index f92e0ee661ae..6d84ca2beead 100644
--- a/fs/cifs/CHANGES
+++ b/fs/cifs/CHANGES
@@ -1,7 +1,9 @@
 Version 1.50
 ------------
 Fix NTLMv2 signing. NFS server mounted over cifs works (if cifs mount is
-done with "serverino" mount option).
+done with "serverino" mount option).  Add support for POSIX Unlink
+(helps with certain sharing violation cases when server such as
+Samba supports newer POSIX CIFS Protocol Extensions).
 
 Version 1.49
 ------------
diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index 9044d9886f0d..6a2056e58ceb 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -2155,6 +2155,12 @@ typedef struct {
         /* struct following varies based on requested level */
 } __attribute__((packed)) OPEN_PSX_RSP; /* level 0x209 SetPathInfo data */
 
+#define SMB_POSIX_UNLINK_FILE_TARGET            0
+#define SMB_POSIX_UNLINK_DIRECTORY_TARGET       1
+
+struct unlink_psx_rq { /* level 0x20a SetPathInfo */
+        __le16 type;
+} __attribute__((packed));
 
 struct file_internal_info {
         __u64  UniqueId; /* inode number */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 3a76c72f3c89..04a69dafedba 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -196,7 +196,10 @@ extern int CIFSSMBMkDir(const int xid, struct cifsTconInfo *tcon,
 extern int CIFSSMBRmDir(const int xid, struct cifsTconInfo *tcon,
                         const char *name, const struct nls_table *nls_codepage,
                         int remap_special_chars);
-
+extern int CIFSPOSIXDelFile(const int xid, struct cifsTconInfo *tcon,
+                        const char *name, __u16 type,
+                        const struct nls_table *nls_codepage,
+                        int remap_special_chars);
 extern int CIFSSMBDelFile(const int xid, struct cifsTconInfo *tcon,
                         const char *name,
                         const struct nls_table *nls_codepage,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 3ab78b776977..b339f5f128da 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -789,6 +789,82 @@ CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
 }
 
 int
+CIFSPOSIXDelFile(const int xid, struct cifsTconInfo *tcon, const char *fileName,
+                 __u16 type, const struct nls_table *nls_codepage, int remap)
+{
+        TRANSACTION2_SPI_REQ *pSMB = NULL;
+        TRANSACTION2_SPI_RSP *pSMBr = NULL;
+        struct unlink_psx_rq *pRqD;
+        int name_len;
+        int rc = 0;
+        int bytes_returned = 0;
+        __u16 params, param_offset, offset, byte_count;
+
+        cFYI(1, ("In POSIX delete"));
+PsxDelete:
+        rc = smb_init(SMB_COM_TRANSACTION2, 15, tcon, (void **) &pSMB,
+                      (void **) &pSMBr);
+        if (rc)
+                return rc;
+
+        if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
+                name_len =
+                    cifsConvertToUCS((__le16 *) pSMB->FileName, fileName,
+                                     PATH_MAX, nls_codepage, remap);
+                name_len++;     /* trailing null */
+                name_len *= 2;
+        } else { /* BB add path length overrun check */
+                name_len = strnlen(fileName, PATH_MAX);
+                name_len++;     /* trailing null */
+                strncpy(pSMB->FileName, fileName, name_len);
+        }
+
+        params = 6 + name_len;
+        pSMB->MaxParameterCount = cpu_to_le16(2);
+        pSMB->MaxDataCount = 0; /* BB double check this with jra */
+        pSMB->MaxSetupCount = 0;
+        pSMB->Reserved = 0;
+        pSMB->Flags = 0;
+        pSMB->Timeout = 0;
+        pSMB->Reserved2 = 0;
+        param_offset = offsetof(struct smb_com_transaction2_spi_req,
+                                InformationLevel) - 4;
+        offset = param_offset + params;
+
+        /* Setup pointer to Request Data (inode type) */
+        pRqD = (struct unlink_psx_rq *)(((char *)&pSMB->hdr.Protocol) + offset);
+        pRqD->type = cpu_to_le16(type);
+        pSMB->ParameterOffset = cpu_to_le16(param_offset);
+        pSMB->DataOffset = cpu_to_le16(offset);
+        pSMB->SetupCount = 1;
+        pSMB->Reserved3 = 0;
+        pSMB->SubCommand = cpu_to_le16(TRANS2_SET_PATH_INFORMATION);
+        byte_count = 3 /* pad */  + params + sizeof(struct unlink_psx_rq);
+
+        pSMB->DataCount = cpu_to_le16(sizeof(struct unlink_psx_rq));
+        pSMB->TotalDataCount = cpu_to_le16(sizeof(struct unlink_psx_rq));
+        pSMB->ParameterCount = cpu_to_le16(params);
+        pSMB->TotalParameterCount = pSMB->ParameterCount;
+        pSMB->InformationLevel = cpu_to_le16(SMB_POSIX_UNLINK);
+        pSMB->Reserved4 = 0;
+        pSMB->hdr.smb_buf_length += byte_count;
+        pSMB->ByteCount = cpu_to_le16(byte_count);
+        rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+                         (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+        if (rc) {
+                cFYI(1, ("Posix delete returned %d", rc));
+        }
+        cifs_buf_release(pSMB);
+
+        cifs_stats_inc(&tcon->num_deletes);
+
+        if (rc == -EAGAIN)
+                goto PsxDelete;
+
+        return rc;
+}
+
+int
 CIFSSMBDelFile(const int xid, struct cifsTconInfo *tcon, const char *fileName,
                const struct nls_table *nls_codepage, int remap)
 {
@@ -933,7 +1009,6 @@ CIFSPOSIXCreate(const int xid, struct cifsTconInfo *tcon, __u32 posix_flags,
         int name_len;
         int rc = 0;
         int bytes_returned = 0;
-        char *data_offset;
         __u16 params, param_offset, offset, byte_count, count;
         OPEN_PSX_REQ * pdata;
         OPEN_PSX_RSP * psx_rsp;
@@ -969,7 +1044,6 @@ PsxCreat:
         param_offset = offsetof(struct smb_com_transaction2_spi_req,
                                 InformationLevel) - 4;
         offset = param_offset + params;
-        data_offset = (char *) (&pSMB->hdr.Protocol) + offset;
         pdata = (OPEN_PSX_REQ *)(((char *)&pSMB->hdr.Protocol) + offset);
         pdata->Level = SMB_QUERY_FILE_UNIX_BASIC;
         pdata->Permissions = cpu_to_le64(mode);
@@ -1671,7 +1745,6 @@ CIFSSMBPosixLock(const int xid, struct cifsTconInfo *tcon,
 {
         struct smb_com_transaction2_sfi_req *pSMB  = NULL;
         struct smb_com_transaction2_sfi_rsp *pSMBr = NULL;
-        char *data_offset;
         struct cifs_posix_lock *parm_data;
         int rc = 0;
         int timeout = 0;
@@ -1698,8 +1771,6 @@ CIFSSMBPosixLock(const int xid, struct cifsTconInfo *tcon,
         param_offset = offsetof(struct smb_com_transaction2_sfi_req, Fid) - 4;
         offset = param_offset + params;
 
-        data_offset = (char *) (&pSMB->hdr.Protocol) + offset;
-
         count = sizeof(struct cifs_posix_lock);
         pSMB->MaxParameterCount = cpu_to_le16(2);
         pSMB->MaxDataCount = cpu_to_le16(1000); /* BB find max SMB PDU from sess */
@@ -2120,9 +2191,7 @@ createSymLinkRetry:
                          (struct smb_hdr *) pSMBr, &bytes_returned, 0);
         cifs_stats_inc(&tcon->num_symlinks);
         if (rc) {
-                cFYI(1,
-                     ("Send error in SetPathInfo (create symlink) = %d",
-                      rc));
+                cFYI(1, ("Send error in SetPathInfo create symlink = %d", rc));
         }
 
         if (pSMB)
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index a1ca55650505..cfa5b360d12e 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -620,9 +620,21 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
                 FreeXid(xid);
                 return -ENOMEM;
         }
-        rc = CIFSSMBDelFile(xid, pTcon, full_path, cifs_sb->local_nls,
+
+        if ((pTcon->ses->capabilities & CAP_UNIX) &&
+                (CIFS_UNIX_POSIX_PATH_OPS_CAP &
+                        le64_to_cpu(pTcon->fsUnixInfo.Capability))) {
+                rc = CIFSPOSIXDelFile(xid, pTcon, full_path,
+                        SMB_POSIX_UNLINK_FILE_TARGET, cifs_sb->local_nls,
                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+                cFYI(1, ("posix del rc %d", rc));
+                if ((rc == 0) || (rc == -ENOENT))
+                        goto psx_del_no_retry;
+        }
 
+        rc = CIFSSMBDelFile(xid, pTcon, full_path, cifs_sb->local_nls,
+                        cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+psx_del_no_retry:
         if (!rc) {
                 if (direntry->d_inode)
                         drop_nlink(direntry->d_inode);