Re: [RFC v10][PATCH 08/13] Dump open file descriptors
From: Al Viro <hidden>
Date: 2008-11-28 10:19:56
Also in:
linux-mm, lkml
On Wed, Nov 26, 2008 at 08:04:39PM -0500, Oren Laadan wrote:
+int cr_scan_fds(struct files_struct *files, int **fdtable)
+{
+ struct fdtable *fdt;
+ int *fds;
+ int i, n = 0;
+ int tot = CR_DEFAULT_FDTABLE;
+
+ fds = kmalloc(tot * sizeof(*fds), GFP_KERNEL);
+ if (!fds)
+ return -ENOMEM;
+
+ /*
+ * We assume that the target task is frozen (or that we checkpoint
+ * ourselves), so we can safely proceed after krealloc() from where
+ * we left off; in the worst cases restart will fail.
+ */Task may be frozen, but it may share the table with any number of other tasks...
+ spin_lock(&files->file_lock);
+ rcu_read_lock();
+ fdt = files_fdtable(files);
+ for (i = 0; i < fdt->max_fds; i++) {
+ if (!fcheck_files(files, i))
+ continue;
+ if (n == tot) {
+ /*
+ * fcheck_files() is safe with drop/re-acquire
+ * of the lock, because it tests: fd < max_fds
+ */
+ spin_unlock(&files->file_lock);
+ rcu_read_unlock();
+ tot *= 2; /* won't overflow: kmalloc will fail */
+ fds = krealloc(fds, tot * sizeof(*fds), GFP_KERNEL);
+ if (!fds)
+ return -ENOMEM;
+ rcu_read_lock();
+ spin_lock(&files->file_lock);
+ }
+ fds[n++] = i;
+ }
+ rcu_read_unlock();
+ spin_unlock(&files->file_lock);
+
+ *fdtable = fds;
+ return n;
+}+ switch (inode->i_mode & S_IFMT) {
+ case S_IFREG:
+ fd_type = CR_FD_FILE;
+ break;
+ case S_IFDIR:
+ fd_type = CR_FD_DIR;
+ break;
+ case S_IFLNK:
+ fd_type = CR_FD_LINK;Opened symlinks? May I have whatever you'd been smoking, please? -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html