Linux kernel compatability enhancements (through 3.19)

[palacios.git] / linux_module / iface-file.c

diff --git a/linux_module/iface-file.c b/linux_module/iface-file.c
index 46d4a28..880c4d9 100644 (file)
--- a/linux_module/iface-file.c
+++ b/linux_module/iface-file.c
@@ -20,6 +20,12 @@ static struct list_head global_files;
 
 #define isprint(a) ((a >= ' ') && (a <= '~'))
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3,9,0)
+#define PAL_VFS_GETATTR(path, kstat) vfs_getattr((path)->mnt, (path)->dentry, kstat)
+#else
+#define PAL_VFS_GETATTR(path, kstat) vfs_getattr(path, kstat)
+#endif
+
 struct palacios_file {
     struct file * filp;
 
@@ -56,6 +62,7 @@ static int mkdir_recursive(const char * path, unsigned short perms) {
     }
 
     memset(tmp_str, 0, strlen(path) + 1);
+    // will terminate tmp_str
     strncpy(tmp_str, path, strlen(path));
 
     dirname_ptr = tmp_str;
@@ -118,6 +125,9 @@ static int palacios_file_mkdir(const char * pathname, unsigned short perms, int
     /* It only exists to provide version compatibility */
     struct path tmp_path; 
 #endif
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,41)
+    struct nameidata nd;
+#endif
 
     struct path * path_ptr = NULL;
     struct dentry * dentry;
@@ -132,8 +142,6 @@ static int palacios_file_mkdir(const char * pathname, unsigned short perms, int
     /* Before Linux 3.1 this was somewhat more difficult */
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,41)
     {
-       struct nameidata nd;
-
        // I'm not 100% sure about the version here, but it was around this time that the API changed
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,38) 
        ret = kern_path_parent(pathname, &nd);
@@ -161,7 +169,7 @@ static int palacios_file_mkdir(const char * pathname, unsigned short perms, int
     {
        dentry = kern_path_create(AT_FDCWD, pathname, &tmp_path, 1);
        
-       if (IS_ERR(dentry)) {
+       if (!dentry || IS_ERR(dentry)) {
            return 0;
        }
        
@@ -170,7 +178,7 @@ static int palacios_file_mkdir(const char * pathname, unsigned short perms, int
 #endif    
 
 
-    if (!IS_ERR(dentry)) {
+    if (!(!dentry || IS_ERR(dentry))) {
        ret = vfs_mkdir(path_ptr->dentry->d_inode, dentry, perms);
     }
 
@@ -218,15 +226,15 @@ static void * palacios_file_open(const char * path, int mode, void * private_dat
     pfile->mode |= O_LARGEFILE;
 
 
-    pfile->filp = filp_open(path, pfile->mode, 0);
+    pfile->filp = filp_open(path, pfile->mode, 0600);  // rw------- to start
     
-    if (IS_ERR(pfile->filp)) {
+    if (!pfile->filp || IS_ERR(pfile->filp)) {
        ERROR("Cannot open file: %s\n", path);
        palacios_free(pfile);
        return NULL;
     }
 
-    pfile->path = palacios_alloc(strlen(path));
+    pfile->path = palacios_alloc(strlen(path) + 1);
     
     if (!pfile->path) { 
        ERROR("Cannot allocate in file open\n");
@@ -234,10 +242,10 @@ static void * palacios_file_open(const char * path, int mode, void * private_dat
        palacios_free(pfile);
        return NULL;
     }
-    strncpy(pfile->path, path, strlen(path));
+    strncpy(pfile->path, path, strlen(path)); // will terminate pfile->path
     pfile->guest = guest;
     
-    spin_lock_init(&(pfile->lock));
+    palacios_spinlock_init(&(pfile->lock));
 
     if (guest == NULL) {
        list_add(&(pfile->file_node), &(global_files));
@@ -252,10 +260,16 @@ static void * palacios_file_open(const char * path, int mode, void * private_dat
 static int palacios_file_close(void * file_ptr) {
     struct palacios_file * pfile = (struct palacios_file *)file_ptr;
 
+    if (!pfile) {
+        return -1;
+    }
+
     filp_close(pfile->filp, NULL);
     
     list_del(&(pfile->file_node));
 
+    palacios_spinlock_deinit(&(pfile->lock));
+
     palacios_free(pfile->path);    
     palacios_free(pfile);
 
@@ -268,7 +282,7 @@ static unsigned long long palacios_file_size(void * file_ptr) {
     struct kstat s;
     int ret;
     
-    ret = vfs_getattr(filp->f_path.mnt, filp->f_path.dentry, &s);
+    ret = PAL_VFS_GETATTR(&(filp->f_path), &s);
 
     if (ret != 0) {
        ERROR("Failed to fstat file\n");
@@ -342,8 +356,14 @@ static int file_init( void ) {
 
 
 static int file_deinit( void ) {
-    if (!list_empty(&(global_files))) {
-       ERROR("Error removing module with open files\n");
+    struct palacios_file * pfile = NULL;
+    struct palacios_file * tmp = NULL;
+    
+    list_for_each_entry_safe(pfile, tmp, &(global_files), file_node) { 
+        filp_close(pfile->filp, NULL);
+        list_del(&(pfile->file_node));
+        palacios_free(pfile->path);    
+        palacios_free(pfile);
     }
 
     return 0;
@@ -368,9 +388,18 @@ static int guest_file_init(struct v3_guest * guest, void ** vm_data) {
 
 
 static int guest_file_deinit(struct v3_guest * guest, void * vm_data) {
+    struct vm_file_state * state = (struct vm_file_state *)vm_data;
+    struct palacios_file * pfile = NULL;
+    struct palacios_file * tmp = NULL;
     
-    palacios_free(vm_data);
+    list_for_each_entry_safe(pfile, tmp, &(state->open_files), file_node) { 
+        filp_close(pfile->filp, NULL);
+        list_del(&(pfile->file_node));
+        palacios_free(pfile->path);    
+        palacios_free(pfile);
+    }
 
+    palacios_free(state);
     return 0;
 }