cifs: merge CIFSSMBQueryEA with CIFSSMBQAllEAs

Add an "ea_name" parameter to CIFSSMBQAllEAs. When it's set make it
behave like CIFSSMBQueryEA does now. The current callers of
CIFSSMBQueryEA are converted to use CIFSSMBQAllEAs, and the old
CIFSSMBQueryEA function is removed.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

4 files changed, 54 insertions, 177 deletions

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 5646727e33f5..88e2bc44ac58 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -363,13 +363,10 @@ extern int CIFSSMBNotify(const int xid, struct cifsTconInfo *tcon,
                         __u32 filter, struct file *file, int multishot,
                         const struct nls_table *nls_codepage);
 extern ssize_t CIFSSMBQAllEAs(const int xid, struct cifsTconInfo *tcon,
-                        const unsigned char *searchName, char *EAData,
+                        const unsigned char *searchName,
+                        const unsigned char *ea_name, char *EAData,
                         size_t bufsize, const struct nls_table *nls_codepage,
                         int remap_special_chars);
-extern ssize_t CIFSSMBQueryEA(const int xid, struct cifsTconInfo *tcon,
-                const unsigned char *searchName, const unsigned char *ea_name,
-                unsigned char *ea_value, size_t buf_size,
-                const struct nls_table *nls_codepage, int remap_special_chars);
 extern int CIFSSMBSetEA(const int xid, struct cifsTconInfo *tcon,
                 const char *fileName, const char *ea_name,
                 const void *ea_value, const __u16 ea_value_len,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index e197e1647d5d..d6d40b883abc 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -5269,12 +5269,22 @@ int CIFSSMBNotify(const int xid, struct cifsTconInfo *tcon,
         cifs_buf_release(pSMB);
         return rc;
 }
+
 #ifdef CONFIG_CIFS_XATTR
+/*
+ * Do a path-based QUERY_ALL_EAS call and parse the result. This is a common
+ * function used by listxattr and getxattr type calls. When ea_name is set,
+ * it looks for that attribute name and stuffs that value into the EAData
+ * buffer. When ea_name is NULL, it stuffs a list of attribute names into the
+ * buffer. In both cases, the return value is either the length of the
+ * resulting data or a negative error code. If EAData is a NULL pointer then
+ * the data isn't copied to it, but the length is returned.
+ */
 ssize_t
 CIFSSMBQAllEAs(const int xid, struct cifsTconInfo *tcon,
-                 const unsigned char *searchName,
-                 char *EAData, size_t buf_size,
-                 const struct nls_table *nls_codepage, int remap)
+                const unsigned char *searchName, const unsigned char *ea_name,
+                char *EAData, size_t buf_size,
+                const struct nls_table *nls_codepage, int remap)
 {
                 /* BB assumes one setup word */
         TRANSACTION2_QPI_REQ *pSMB = NULL;
@@ -5403,27 +5413,46 @@ QAllEAsRetry:
                         goto QAllEAsOut;
                 }
 
-                /* account for prefix user. and trailing null */
-                rc += (5 + 1 + name_len);
-                if (rc < (int) buf_size) {
-                        memcpy(EAData, "user.", 5);
-                        EAData += 5;
-                        memcpy(EAData, temp_ptr, name_len);
-                        EAData += name_len;
-                        /* null terminate name */
-                        *EAData = 0;
-                        ++EAData;
-                } else if (buf_size == 0) {
-                        /* skip copy - calc size only */
+                if (ea_name) {
+                        if (strncmp(ea_name, temp_ptr, name_len) == 0) {
+                                temp_ptr += name_len + 1;
+                                rc = value_len;
+                                if (buf_size == 0)
+                                        goto QAllEAsOut;
+                                if ((size_t)value_len > buf_size) {
+                                        rc = -ERANGE;
+                                        goto QAllEAsOut;
+                                }
+                                memcpy(EAData, temp_ptr, value_len);
+                                goto QAllEAsOut;
+                        }
                 } else {
-                        /* stop before overrun buffer */
-                        rc = -ERANGE;
-                        break;
+                        /* account for prefix user. and trailing null */
+                        rc += (5 + 1 + name_len);
+                        if (rc < (int) buf_size) {
+                                memcpy(EAData, "user.", 5);
+                                EAData += 5;
+                                memcpy(EAData, temp_ptr, name_len);
+                                EAData += name_len;
+                                /* null terminate name */
+                                *EAData = 0;
+                                ++EAData;
+                        } else if (buf_size == 0) {
+                                /* skip copy - calc size only */
+                        } else {
+                                /* stop before overrun buffer */
+                                rc = -ERANGE;
+                                break;
+                        }
                 }
                 temp_ptr += name_len + 1 + value_len;
                 temp_fea = (struct fea *)temp_ptr;
         }
 
+        /* didn't find the named attribute */
+        if (ea_name)
+                rc = -ENODATA;
+
 QAllEAsOut:
         cifs_buf_release(pSMB);
         if (rc == -EAGAIN)
@@ -5432,155 +5461,6 @@ QAllEAsOut:
         return (ssize_t)rc;
 }
 
-ssize_t CIFSSMBQueryEA(const int xid, struct cifsTconInfo *tcon,
-                const unsigned char *searchName, const unsigned char *ea_name,
-                unsigned char *ea_value, size_t buf_size,
-                const struct nls_table *nls_codepage, int remap)
-{
-        TRANSACTION2_QPI_REQ *pSMB = NULL;
-        TRANSACTION2_QPI_RSP *pSMBr = NULL;
-        int rc = 0;
-        int bytes_returned;
-        int name_len;
-        struct fea *temp_fea;
-        char *temp_ptr;
-        __u16 params, byte_count;
-
-        cFYI(1, ("In Query EA path %s", searchName));
-QEARetry:
-        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, searchName,
-                                     PATH_MAX, nls_codepage, remap);
-                name_len++;     /* trailing null */
-                name_len *= 2;
-        } else {        /* BB improve the check for buffer overruns BB */
-                name_len = strnlen(searchName, PATH_MAX);
-                name_len++;     /* trailing null */
-                strncpy(pSMB->FileName, searchName, name_len);
-        }
-
-        params = 2 /* level */ + 4 /* reserved */ + name_len /* includes NUL */;
-        pSMB->TotalDataCount = 0;
-        pSMB->MaxParameterCount = cpu_to_le16(2);
-        /* BB find exact max SMB PDU from sess structure BB */
-        pSMB->MaxDataCount = cpu_to_le16(4000);
-        pSMB->MaxSetupCount = 0;
-        pSMB->Reserved = 0;
-        pSMB->Flags = 0;
-        pSMB->Timeout = 0;
-        pSMB->Reserved2 = 0;
-        pSMB->ParameterOffset = cpu_to_le16(offsetof(
-                struct smb_com_transaction2_qpi_req, InformationLevel) - 4);
-        pSMB->DataCount = 0;
-        pSMB->DataOffset = 0;
-        pSMB->SetupCount = 1;
-        pSMB->Reserved3 = 0;
-        pSMB->SubCommand = cpu_to_le16(TRANS2_QUERY_PATH_INFORMATION);
-        byte_count = params + 1 /* pad */ ;
-        pSMB->TotalParameterCount = cpu_to_le16(params);
-        pSMB->ParameterCount = pSMB->TotalParameterCount;
-        pSMB->InformationLevel = cpu_to_le16(SMB_INFO_QUERY_ALL_EAS);
-        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, ("Send error in Query EA = %d", rc));
-        } else {                /* decode response */
-                rc = validate_t2((struct smb_t2_rsp *)pSMBr);
-
-                /* BB also check enough total bytes returned */
-                /* BB we need to improve the validity checking
-                of these trans2 responses */
-                if (rc || (pSMBr->ByteCount < 4))
-                        rc = -EIO;      /* bad smb */
-           /* else if (pFindData){