--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ *
+ * Author: Marc Vef <mvef@whamcloud.com>
+ */
+
+#include <linux/rbtree.h>
+#include <lustre_net.h>
+#include "nodemap_internal.h"
+
+/**
+ * Allocate a lu_fileset_alt structure with a given fileset size.
+ *
+ * \param fileset_size size of the fileset path
+ *
+ * \retval allocated lu_fileset_alt structure on success, NULL otherwise
+ */
+struct lu_fileset_alt *fileset_alt_init(unsigned int fileset_size)
+{
+ struct lu_fileset_alt *fileset;
+
+ OBD_ALLOC_PTR(fileset);
+ if (fileset == NULL)
+ RETURN(NULL);
+
+ fileset->nfa_path_size = fileset_size;
+ fileset->nfa_id = 0; /* is set later on tree insertion */
+
+ OBD_ALLOC(fileset->nfa_path, fileset->nfa_path_size);
+ if (fileset->nfa_path == NULL) {
+ OBD_FREE_PTR(fileset);
+ RETURN(NULL);
+ }
+
+ return fileset;
+}
+EXPORT_SYMBOL(fileset_alt_init);
+
+/**
+ * Create a lu_fileset_alt structure with a given fileset path.
+ *
+ * \param fileset_path fileset path
+ *
+ * \retval allocated lu_fileset_alt structure on success, NULL otherwise
+ */
+struct lu_fileset_alt *fileset_alt_create(const char *fileset_path)
+{
+ struct lu_fileset_alt *fileset;
+
+ fileset = fileset_alt_init(strlen(fileset_path) + 1);
+ if (fileset == NULL)
+ RETURN(NULL);
+
+ memcpy(fileset->nfa_path, fileset_path, fileset->nfa_path_size);
+
+ return fileset;
+}
+EXPORT_SYMBOL(fileset_alt_create);
+
+void fileset_alt_destroy(struct lu_fileset_alt *fileset)
+{
+ OBD_FREE(fileset->nfa_path, fileset->nfa_path_size);
+ OBD_FREE_PTR(fileset);
+}
+EXPORT_SYMBOL(fileset_alt_destroy);
+
+void fileset_alt_destroy_tree(struct rb_root *root)
+{
+ struct lu_fileset_alt *fileset;
+ struct lu_fileset_alt *tmp;
+
+ rbtree_postorder_for_each_entry_safe(fileset, tmp, root, nfa_rb)
+ fileset_alt_destroy(fileset);
+
+ *root = RB_ROOT;
+}
+EXPORT_SYMBOL(fileset_alt_destroy_tree);
+
+/**
+ * Helper function to find the first free id in the rb tree on insertion.
+ *
+ * \param root pointer to the root of the rb tree
+ *
+ * \retval >0 first free id
+ */
+static unsigned int get_first_free_id(struct rb_root *root)
+{
+ struct rb_node *node;
+ struct lu_fileset_alt *fileset;
+ /* start at 1. 0 is reserved for the prim fileset in another context */
+ unsigned int fset_id = 1;
+
+ /* iterate over the tree and find gaps in the id sequence */
+ for (node = rb_first(root); node; node = rb_next(node)) {
+ fileset = rb_entry(node, struct lu_fileset_alt, nfa_rb);
+ if (fileset->nfa_id != fset_id)
+ RETURN(fset_id);
+ fset_id++;
+ }
+
+ /* no gaps found, return the next id after the last one in the tree */
+ return fset_id;
+}
+
+/**
+ * Insert a fileset into the rb tree. If fileset->nfa_id is 0, the first free
+ * id is assigned and used. The caller is free to set its own fileset->nfa_id
+ * as long as it is not 0.
+ *
+ * \param root pointer to the root of the rb tree
+ * \param fileset fileset to insert
+ *
+ * \retval 0 on success
+ * \retval -EEXIST if the fileset id already exists
+ * \retval -ENOSPC if the fileset id exceeds
+ * LUSTRE_NODEMAP_FILESET_NUM_MAX
+ */
+int fileset_alt_add(struct rb_root *root, struct lu_fileset_alt *fileset)
+{
+ struct rb_node **new = &(root->rb_node);
+ struct rb_node *parent = NULL;
+ struct lu_fileset_alt *this = NULL;
+
+ if (fileset->nfa_id == 0)
+ fileset->nfa_id = get_first_free_id(root);
+
+ if (fileset->nfa_id > LUSTRE_NODEMAP_FILESET_NUM_MAX - 1)
+ return -ENOSPC;
+
+ /* determine the correct position in the tree */
+ while (*new) {
+ this = rb_entry(*new, struct lu_fileset_alt, nfa_rb);
+ parent = *new;
+ if (fileset->nfa_id < this->nfa_id)
+ new = &((*new)->rb_left);
+ else if (fileset->nfa_id > this->nfa_id)
+ new = &((*new)->rb_right);
+ else
+ return -EEXIST;
+ }
+
+ /* insert the new node and rebalance tree */
+ rb_link_node(&fileset->nfa_rb, parent, new);
+ rb_insert_color(&fileset->nfa_rb, root);
+
+ return 0;
+}
+EXPORT_SYMBOL(fileset_alt_add);
+
+/**
+ * Delete a fileset from the rb tree.
+ *
+ * \param root pointer to the root of the rb tree
+ * \param fileset fileset to delete
+ * \retval >0 id of the deleted fileset
+ * \retval -EINVAL fileset is NULL
+ */
+int fileset_alt_delete(struct rb_root *root, struct lu_fileset_alt *fileset)
+{
+ unsigned int fset_id;
+
+ if (fileset == NULL)
+ return -EINVAL;
+
+ fset_id = fileset->nfa_id;
+ rb_erase(&fileset->nfa_rb, root);
+ fileset_alt_destroy(fileset);
+
+ return fset_id;
+}
+EXPORT_SYMBOL(fileset_alt_delete);
+
+static int compare_by_id(const void *key, const struct rb_node *node)
+{
+ const int *search_id;
+ struct lu_fileset_alt *fileset;
+ int rc;
+
+ search_id = key;
+ fileset = rb_entry(node, struct lu_fileset_alt, nfa_rb);
+
+ if (*search_id < fileset->nfa_id)
+ rc = -1;
+ else if (*search_id > fileset->nfa_id)
+ rc = 1;
+ else
+ rc = 0;
+
+ return rc;
+}
+
+/**
+ * Search for a fileset by its fileset id.
+ *
+ * \param root pointer to the root of the rb tree
+ * \param fileset_id id of the fileset to search
+ *
+ * \retval lu_fileset_alt structure on success, NULL otherwise
+ */
+struct lu_fileset_alt *fileset_alt_search_id(struct rb_root *root,
+ unsigned int fileset_id)
+{
+ struct lu_fileset_alt *fileset = NULL;
+ struct rb_node *node;
+
+ node = rb_find(&fileset_id, root, compare_by_id);
+ if (node)
+ fileset = rb_entry(node, struct lu_fileset_alt, nfa_rb);
+
+ return fileset;
+}
+EXPORT_SYMBOL(fileset_alt_search_id);
+
+/**
+ * Search for a fileset by its fileset path.
+ *
+ * \param root pointer to the root of the rb tree
+ * \param fileset_path path of the fileset to search
+ *
+ * \retval lu_fileset_alt structure on success, NULL otherwise
+ */
+struct lu_fileset_alt *fileset_alt_search_path(struct rb_root *root,
+ const char *fileset_path)
+{
+ struct rb_node *node;
+ struct lu_fileset_alt *fileset;
+ bool found = false;
+ int rc;
+
+ /* search the full tree for a fileset with the given path */
+ for (node = rb_first(root); node; node = rb_next(node)) {
+ fileset = rb_entry(node, struct lu_fileset_alt, nfa_rb);
+ rc = strcmp(fileset_path, fileset->nfa_path);
+ if (!rc) {
+ found = true;
+ break;
+ }
+ }
+ return found ? fileset : NULL;
+}
+EXPORT_SYMBOL(fileset_alt_search_path);
+
+bool fileset_alt_path_exists(struct rb_root *root, const char *path)
+{
+ return fileset_alt_search_path(root, path) != NULL;
+}
+EXPORT_SYMBOL(fileset_alt_path_exists);
+
+/**
+ * Iterate over all rb tree entries and shrink the memory requirements
+ * for the fileset to the actual needed size. This is required when the
+ * fileset fragments are read from the nodemap IAM, and so the preallocated
+ * size may be larger than needed.
+ *
+ * \param root pointer to the root of the rb tree
+ */
+void fileset_alt_resize(struct rb_root *root)
+{
+ struct rb_node *node;
+ struct lu_fileset_alt *fileset;
+ unsigned int fset_size_actual, fset_size_prealloc;
+ char *fset_tmp;
+
+ for (node = rb_first(root); node; node = rb_next(node)) {
+ fileset = rb_entry(node, struct lu_fileset_alt, nfa_rb);
+ fset_size_prealloc = fileset->nfa_path_size;
+ fset_size_actual = strlen(fileset->nfa_path) + 1;
+ if (fset_size_actual == fset_size_prealloc)
+ continue;
+ /* Shrink fileset size to actual */
+ OBD_ALLOC(fset_tmp, fset_size_actual);
+ if (!fset_tmp) {
+ CERROR("%s: Nodemaps's fileset cannot be resized: rc = %d\n",
+ fileset->nfa_path, -ENOMEM);
+ continue;
+ }
+
+ memcpy(fset_tmp, fileset->nfa_path, fset_size_actual);
+
+ OBD_FREE(fileset->nfa_path, fset_size_prealloc);
+
+ fileset->nfa_path = fset_tmp;
+ fileset->nfa_path_size = fset_size_actual;
+ }
+}
+EXPORT_SYMBOL(fileset_alt_resize);
git://git.whamcloud.com / fs / lustre-release.git / commitdiff