queue: consolidate kdbus_queue_entry_*fds_install()

Combine code from kdbus_queue_entry_fds_install() and
kdbus_queue_entry_memfds_install() and make simplify the caller site.

Signed-off-by: Daniel Mack <daniel@zonque.org>

diff --git a/queue.c b/queue.c
index 914dc8292ec56f226c743a822603eb10966f48ee..6693852f7ba81258e82053cca88645f3fd58c231 100644 (file)
--- a/queue.c
+++ b/queue.c
@@ -35,94 +35,71 @@
 #include "util.h"
 #include "queue.h"
 
-static int kdbus_queue_entry_fds_install(struct kdbus_queue_entry *entry,
-                                        int **ret_fds)
+static int kdbus_queue_entry_fds_install(struct kdbus_queue_entry *entry)
 {
        unsigned int i;
        int ret, *fds;
-       size_t size;
+       size_t count;
 
        /* get array of file descriptors */
-       size = entry->fds_count * sizeof(int);
-       fds = kmalloc(size, GFP_KERNEL);
+       count = entry->fds_count + entry->memfds_count;
+       if (!count)
+               return 0;
+
+       fds = kcalloc(count, sizeof(int), GFP_KERNEL);
        if (!fds)
                return -ENOMEM;
 
        /* allocate new file descriptors in the receiver's process */
-       for (i = 0; i < entry->fds_count; i++) {
+       for (i = 0; i < count; i++) {
                fds[i] = get_unused_fd_flags(O_CLOEXEC);
                if (fds[i] < 0) {
                        ret = fds[i];
-                       goto remove_unused;
+                       goto exit_remove_unused;
                }
        }
 
-       /* copy the array into the message item */
-       ret = kdbus_pool_slice_copy(entry->slice, entry->fds, fds, size);
-       if (ret < 0)
-               goto remove_unused;
-
-       /* install files in the receiver's process */
-       for (i = 0; i < entry->fds_count; i++)
-               fd_install(fds[i], get_file(entry->fds_fp[i]));
-
-       kfree(fds);
-       return 0;
-
-remove_unused:
-       for (i = 0; i < entry->fds_count; i++) {
-               if (fds[i] < 0)
-                       break;
+       if (entry->fds_count) {
+               /* copy the array into the message item */
+               ret = kdbus_pool_slice_copy(entry->slice, entry->fds, fds,
+                                           entry->fds_count * sizeof(int));
+               if (ret < 0)
+                       goto exit_remove_unused;
 
-               put_unused_fd(fds[i]);
+               /* install files in the receiver's process */
+               for (i = 0; i < entry->fds_count; i++)
+                       fd_install(fds[i], get_file(entry->fds_fp[i]));
        }
 
-       *ret_fds = fds;
-       return ret;
-}
-
-static int kdbus_queue_entry_memfds_install(struct kdbus_queue_entry *entry,
-                                           int **memfds)
-{
-       int *fds;
-       unsigned int i;
-       size_t size;
-       int ret = 0;
-
-       size = entry->memfds_count * sizeof(int);
-       fds = kmalloc(size, GFP_KERNEL);
-       if (!fds)
-               return -ENOMEM;
+       if (entry->memfds_count) {
+               off_t o = entry->fds_count;
 
-       /* allocate new file descriptors in the receiver's process */
-       for (i = 0; i < entry->memfds_count; i++) {
-               fds[i] = get_unused_fd_flags(O_CLOEXEC);
-               if (fds[i] < 0) {
-                       ret = fds[i];
-                       goto remove_unused;
+               /*
+                * Update the file descriptor number in the items.
+                * We remembered the locations of the values in the buffer.
+                */
+               for (i = 0; i < entry->memfds_count; i++) {
+                       ret = kdbus_pool_slice_copy(entry->slice,
+                                                   entry->memfds[i],
+                                                   &fds[o + i], sizeof(int));
+                       if (ret < 0)
+                               goto exit_rewind_fds;
                }
-       }
 
-       /*
-        * Update the file descriptor number in the items. We remembered
-        * the locations of the values in the buffer.
-        */
-       for (i = 0; i < entry->memfds_count; i++) {
-               ret = kdbus_pool_slice_copy(entry->slice, entry->memfds[i],
-                                            &fds[i], sizeof(int));
-               if (ret < 0)
-                       goto remove_unused;
+               /* install files in the receiver's process */
+               for (i = 0; i < entry->memfds_count; i++)
+                       fd_install(fds[o + i], get_file(entry->memfds_fp[i]));
        }
 
-       /* install files in the receiver's process */
-       for (i = 0; i < entry->memfds_count; i++)
-               fd_install(fds[i], get_file(entry->memfds_fp[i]));
-
-       *memfds = fds;
+       kfree(fds);
        return 0;
 
-remove_unused:
-       for (i = 0; i < entry->memfds_count; i++) {
+exit_rewind_fds:
+       for (i = 0; i < entry->fds_count; i++)
+               sys_close(fds[i]);
+
+exit_remove_unused:
+       for (i = 0; i < count; i++) {
                if (fds[i] < 0)
                        break;
 
@@ -130,7 +107,6 @@ remove_unused:
        }
 
        kfree(fds);
-       *memfds = NULL;
        return ret;
 }
 
@@ -150,38 +126,16 @@ int kdbus_queue_entry_install(struct kdbus_queue_entry *entry)
 {
        int *memfds = NULL;
        int *fds = NULL;
-       unsigned int i;
        int ret = 0;
 
-       /*
-        * Install KDBUS_MSG_PAYLOAD_MEMFDs file descriptors, we return
-        * the list of file descriptors to be able to cleanup on error.
-        */
-       if (entry->memfds_count > 0) {
-               ret = kdbus_queue_entry_memfds_install(entry, &memfds);
-               if (ret < 0)
-                       return ret;
-       }
-
-       /* install KDBUS_MSG_FDS file descriptors */
-       if (entry->fds_count > 0) {
-               ret = kdbus_queue_entry_fds_install(entry, &fds);
-               if (ret < 0)
-                       goto exit_rewind_memfds;
-       }
+       ret = kdbus_queue_entry_fds_install(entry);
+       if (ret < 0)
+               return ret;
 
        kfree(fds);
        kfree(memfds);
        kdbus_pool_slice_flush(entry->slice);
-
        return 0;
-
-exit_rewind_memfds:
-       for (i = 0; i < entry->memfds_count; i++)
-               sys_close(memfds[i]);
-       kfree(memfds);
-
-       return ret;
 }
 
 static int kdbus_queue_entry_payload_add(struct kdbus_queue_entry *entry,