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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-14 19:10:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-14 19:10:49 +0000 |
commit | cfe5e3905201349e9cf3f95d52ff4bd100bde37d (patch) | |
tree | d0baf160cbee3195249d095f85e52d20c21acf02 /misc-utils/lsblk-devtree.c | |
parent | Initial commit. (diff) | |
download | util-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.tar.xz util-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.zip |
Adding upstream version 2.39.3.upstream/2.39.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'misc-utils/lsblk-devtree.c')
-rw-r--r-- | misc-utils/lsblk-devtree.c | 564 |
1 files changed, 564 insertions, 0 deletions
diff --git a/misc-utils/lsblk-devtree.c b/misc-utils/lsblk-devtree.c new file mode 100644 index 0000000..5e4ff4c --- /dev/null +++ b/misc-utils/lsblk-devtree.c @@ -0,0 +1,564 @@ +/* + * These functions implement tree of block devices. The devtree struct contains + * two basic lists: + * + * 1) devtree->devices -- This is simple list without any hierarchy. We use + * reference counting here. + * + * 2) devtree->roots -- The root nodes of the trees. The code does not use + * reference counting here due to complexity and it's unnecessary. + * + * Note that the same device maybe have more parents and more children. The + * device is allocated only once and shared within the tree. The dependence + * (devdep struct) contains reference to child as well as to parent and the + * dependence is reference by ls_childs from parent device and by ls_parents + * from child. (Yes, "childs" is used for children ;-) + * + * Copyright (C) 2018 Karel Zak <kzak@redhat.com> + */ +#include "lsblk.h" +#include "sysfs.h" +#include "pathnames.h" + + +void lsblk_reset_iter(struct lsblk_iter *itr, int direction) +{ + if (direction == -1) + direction = itr->direction; + + memset(itr, 0, sizeof(*itr)); + itr->direction = direction; +} + +struct lsblk_device *lsblk_new_device(void) +{ + struct lsblk_device *dev; + + dev = calloc(1, sizeof(*dev)); + if (!dev) + return NULL; + + dev->refcount = 1; + dev->removable = -1; + dev->discard_granularity = (uint64_t) -1; + + INIT_LIST_HEAD(&dev->childs); + INIT_LIST_HEAD(&dev->parents); + INIT_LIST_HEAD(&dev->ls_roots); + INIT_LIST_HEAD(&dev->ls_devices); + + DBG(DEV, ul_debugobj(dev, "alloc")); + return dev; +} + +void lsblk_ref_device(struct lsblk_device *dev) +{ + if (dev) + dev->refcount++; +} + +/* removes dependence from child as well as from parent */ +static int remove_dependence(struct lsblk_devdep *dep) +{ + if (!dep) + return -EINVAL; + + DBG(DEP, ul_debugobj(dep, " dealloc")); + + list_del_init(&dep->ls_childs); + list_del_init(&dep->ls_parents); + + free(dep); + return 0; +} + +static int device_remove_dependences(struct lsblk_device *dev) +{ + if (!dev) + return -EINVAL; + + if (!list_empty(&dev->childs)) + DBG(DEV, ul_debugobj(dev, " %s: remove all children deps", dev->name)); + while (!list_empty(&dev->childs)) { + struct lsblk_devdep *dp = list_entry(dev->childs.next, + struct lsblk_devdep, ls_childs); + remove_dependence(dp); + } + + if (!list_empty(&dev->parents)) + DBG(DEV, ul_debugobj(dev, " %s: remove all parents deps", dev->name)); + while (!list_empty(&dev->parents)) { + struct lsblk_devdep *dp = list_entry(dev->parents.next, + struct lsblk_devdep, ls_parents); + remove_dependence(dp); + } + + return 0; +} + +void lsblk_unref_device(struct lsblk_device *dev) +{ + if (!dev) + return; + + if (--dev->refcount <= 0) { + DBG(DEV, ul_debugobj(dev, " freeing [%s] <<", dev->name)); + + device_remove_dependences(dev); + lsblk_device_free_properties(dev->properties); + lsblk_device_free_filesystems(dev); + + lsblk_unref_device(dev->wholedisk); + + free(dev->dm_name); + free(dev->filename); + free(dev->dedupkey); + + ul_unref_path(dev->sysfs); + + DBG(DEV, ul_debugobj(dev, " >> dealloc [%s]", dev->name)); + free(dev->name); + free(dev); + } +} + +int lsblk_device_has_child(struct lsblk_device *dev, struct lsblk_device *child) +{ + struct lsblk_device *x = NULL; + struct lsblk_iter itr; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (lsblk_device_next_child(dev, &itr, &x) == 0) { + if (x == child) + return 1; + } + + return 0; +} + +int lsblk_device_new_dependence(struct lsblk_device *parent, struct lsblk_device *child) +{ + struct lsblk_devdep *dp; + + if (!parent || !child) + return -EINVAL; + + if (lsblk_device_has_child(parent, child)) + return 1; + + dp = calloc(1, sizeof(*dp)); + if (!dp) + return -ENOMEM; + + INIT_LIST_HEAD(&dp->ls_childs); + INIT_LIST_HEAD(&dp->ls_parents); + + dp->child = child; + list_add_tail(&dp->ls_childs, &parent->childs); + + dp->parent = parent; + list_add_tail(&dp->ls_parents, &child->parents); + + DBG(DEV, ul_debugobj(parent, "add dependence 0x%p [%s->%s]", dp, parent->name, child->name)); + + return 0; +} + +static int device_next_child(struct lsblk_device *dev, + struct lsblk_iter *itr, + struct lsblk_devdep **dp) +{ + int rc = 1; + + if (!dev || !itr || !dp) + return -EINVAL; + *dp = NULL; + + if (!itr->head) + LSBLK_ITER_INIT(itr, &dev->childs); + if (itr->p != itr->head) { + LSBLK_ITER_ITERATE(itr, *dp, struct lsblk_devdep, ls_childs); + rc = 0; + } + + return rc; +} + +int lsblk_device_next_child(struct lsblk_device *dev, + struct lsblk_iter *itr, + struct lsblk_device **child) +{ + struct lsblk_devdep *dp = NULL; + int rc = device_next_child(dev, itr, &dp); + + if (!child) + return -EINVAL; + + *child = rc == 0 ? dp->child : NULL; + return rc; +} + +int lsblk_device_is_last_parent(struct lsblk_device *dev, struct lsblk_device *parent) +{ + struct lsblk_devdep *dp = list_last_entry( + &dev->parents, + struct lsblk_devdep, ls_parents); + if (!dp) + return 0; + return dp->parent == parent; +} + +int lsblk_device_next_parent( + struct lsblk_device *dev, + struct lsblk_iter *itr, + struct lsblk_device **parent) +{ + int rc = 1; + + if (!dev || !itr || !parent) + return -EINVAL; + *parent = NULL; + + if (!itr->head) + LSBLK_ITER_INIT(itr, &dev->parents); + if (itr->p != itr->head) { + struct lsblk_devdep *dp = NULL; + LSBLK_ITER_ITERATE(itr, dp, struct lsblk_devdep, ls_parents); + if (dp) + *parent = dp->parent; + rc = 0; + } + + return rc; +} + +struct lsblk_devtree *lsblk_new_devtree(void) +{ + struct lsblk_devtree *tr; + + tr = calloc(1, sizeof(*tr)); + if (!tr) + return NULL; + + tr->refcount = 1; + + INIT_LIST_HEAD(&tr->roots); + INIT_LIST_HEAD(&tr->devices); + INIT_LIST_HEAD(&tr->pktcdvd_map); + + DBG(TREE, ul_debugobj(tr, "alloc")); + return tr; +} + +void lsblk_ref_devtree(struct lsblk_devtree *tr) +{ + if (tr) + tr->refcount++; +} + +void lsblk_unref_devtree(struct lsblk_devtree *tr) +{ + if (!tr) + return; + + if (--tr->refcount <= 0) { + DBG(TREE, ul_debugobj(tr, "dealloc")); + + while (!list_empty(&tr->devices)) { + struct lsblk_device *dev = list_entry(tr->devices.next, + struct lsblk_device, ls_devices); + lsblk_devtree_remove_device(tr, dev); + } + + while (!list_empty(&tr->pktcdvd_map)) { + struct lsblk_devnomap *map = list_entry(tr->pktcdvd_map.next, + struct lsblk_devnomap, ls_devnomap); + list_del(&map->ls_devnomap); + free(map); + } + + free(tr); + } +} + +static int has_root(struct lsblk_devtree *tr, struct lsblk_device *dev) +{ + struct lsblk_iter itr; + struct lsblk_device *x = NULL; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (lsblk_devtree_next_root(tr, &itr, &x) == 0) { + if (x == dev) + return 1; + } + return 0; +} + +int lsblk_devtree_add_root(struct lsblk_devtree *tr, struct lsblk_device *dev) +{ + if (has_root(tr, dev)) + return 0; + + if (!lsblk_devtree_has_device(tr, dev)) + lsblk_devtree_add_device(tr, dev); + + /* We don't increment reference counter for tr->roots list. The primary + * reference is tr->devices */ + + DBG(TREE, ul_debugobj(tr, "add root device 0x%p [%s]", dev, dev->name)); + list_add_tail(&dev->ls_roots, &tr->roots); + return 0; +} + +int lsblk_devtree_remove_root(struct lsblk_devtree *tr __attribute__((unused)), + struct lsblk_device *dev) +{ + DBG(TREE, ul_debugobj(tr, "remove root device 0x%p [%s]", dev, dev->name)); + list_del_init(&dev->ls_roots); + + return 0; +} + +int lsblk_devtree_next_root(struct lsblk_devtree *tr, + struct lsblk_iter *itr, + struct lsblk_device **dev) +{ + int rc = 1; + + if (!tr || !itr || !dev) + return -EINVAL; + *dev = NULL; + if (!itr->head) + LSBLK_ITER_INIT(itr, &tr->roots); + if (itr->p != itr->head) { + LSBLK_ITER_ITERATE(itr, *dev, struct lsblk_device, ls_roots); + rc = 0; + } + return rc; +} + +int lsblk_devtree_add_device(struct lsblk_devtree *tr, struct lsblk_device *dev) +{ + lsblk_ref_device(dev); + + DBG(TREE, ul_debugobj(tr, "add device 0x%p [%s]", dev, dev->name)); + list_add_tail(&dev->ls_devices, &tr->devices); + return 0; +} + +int lsblk_devtree_next_device(struct lsblk_devtree *tr, + struct lsblk_iter *itr, + struct lsblk_device **dev) +{ + int rc = 1; + + if (!tr || !itr || !dev) + return -EINVAL; + *dev = NULL; + if (!itr->head) + LSBLK_ITER_INIT(itr, &tr->devices); + if (itr->p != itr->head) { + LSBLK_ITER_ITERATE(itr, *dev, struct lsblk_device, ls_devices); + rc = 0; + } + return rc; +} + +int lsblk_devtree_has_device(struct lsblk_devtree *tr, struct lsblk_device *dev) +{ + struct lsblk_device *x = NULL; + struct lsblk_iter itr; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (lsblk_devtree_next_device(tr, &itr, &x) == 0) { + if (x == dev) + return 1; + } + + return 0; +} + +struct lsblk_device *lsblk_devtree_get_device(struct lsblk_devtree *tr, const char *name) +{ + struct lsblk_device *dev = NULL; + struct lsblk_iter itr; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (lsblk_devtree_next_device(tr, &itr, &dev) == 0) { + if (strcmp(name, dev->name) == 0) + return dev; + } + + return NULL; +} + +int lsblk_devtree_remove_device(struct lsblk_devtree *tr, struct lsblk_device *dev) +{ + DBG(TREE, ul_debugobj(tr, "remove device 0x%p [%s]", dev, dev->name)); + + if (!lsblk_devtree_has_device(tr, dev)) + return 1; + + list_del_init(&dev->ls_roots); + list_del_init(&dev->ls_devices); + lsblk_unref_device(dev); + + return 0; +} + +static void read_pktcdvd_map(struct lsblk_devtree *tr) +{ + char buf[PATH_MAX]; + FILE *f; + + assert(tr->pktcdvd_read == 0); + + f = ul_path_fopen(NULL, "r", _PATH_SYS_CLASS "/pktcdvd/device_map"); + if (!f) + goto done; + + while (fgets(buf, sizeof(buf), f)) { + struct lsblk_devnomap *map; + int pkt_maj, pkt_min, blk_maj, blk_min; + + if (sscanf(buf, "%*s %d:%d %d:%d\n", + &pkt_maj, &pkt_min, + &blk_maj, &blk_min) != 4) + continue; + + map = malloc(sizeof(*map)); + if (!map) + break; + map->holder = makedev(pkt_maj, pkt_min); + map->slave = makedev(blk_maj, blk_min); + INIT_LIST_HEAD(&map->ls_devnomap); + list_add_tail(&map->ls_devnomap, &tr->pktcdvd_map); + } + + fclose(f); +done: + tr->pktcdvd_read = 1; +} + +/* returns opposite device of @devno for blk->pkt relation -- e.g. if devno + * is_slave (blk) then returns holder (pkt) and vice-versa */ +dev_t lsblk_devtree_pktcdvd_get_mate(struct lsblk_devtree *tr, dev_t devno, int is_slave) +{ + struct list_head *p; + + if (!tr->pktcdvd_read) + read_pktcdvd_map(tr); + if (list_empty(&tr->pktcdvd_map)) + return 0; + + list_for_each(p, &tr->pktcdvd_map) { + struct lsblk_devnomap *x = list_entry(p, struct lsblk_devnomap, ls_devnomap); + + if (is_slave && devno == x->slave) + return x->holder; + if (!is_slave && devno == x->holder) + return x->slave; + } + return 0; +} + +static int device_dedupkey_is_equal( + struct lsblk_device *dev, + struct lsblk_device *pattern) +{ + assert(pattern->dedupkey); + + if (!dev->dedupkey || dev == pattern) + return 0; + if (strcmp(dev->dedupkey, pattern->dedupkey) == 0) { + if (!device_is_partition(dev) || + !dev->wholedisk->dedupkey || + strcmp(dev->dedupkey, dev->wholedisk->dedupkey) != 0) { + DBG(DEV, ul_debugobj(dev, "%s: match deduplication pattern", dev->name)); + return 1; + } + } + return 0; +} + +static void device_dedup_dependencies( + struct lsblk_device *dev, + struct lsblk_device *pattern) +{ + struct lsblk_iter itr; + struct lsblk_devdep *dp; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (device_next_child(dev, &itr, &dp) == 0) { + struct lsblk_device *child = dp->child; + + if (device_dedupkey_is_equal(child, pattern)) { + DBG(DEV, ul_debugobj(dev, "remove duplicate dependence: 0x%p [%s]", + dp->child, dp->child->name)); + remove_dependence(dp); + } else + device_dedup_dependencies(child, pattern); + } +} + +static void devtree_dedup(struct lsblk_devtree *tr, struct lsblk_device *pattern) +{ + struct lsblk_iter itr; + struct lsblk_device *dev = NULL; + + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + DBG(TREE, ul_debugobj(tr, "de-duplicate by key: %s", pattern->dedupkey)); + + while (lsblk_devtree_next_root(tr, &itr, &dev) == 0) { + if (device_dedupkey_is_equal(dev, pattern)) { + DBG(TREE, ul_debugobj(tr, "remove duplicate device: 0x%p [%s]", + dev, dev->name)); + /* Note that root list does not use ref-counting; the + * primary reference is ls_devices */ + list_del_init(&dev->ls_roots); + } else + device_dedup_dependencies(dev, pattern); + } +} + +static int cmp_devices_devno(struct list_head *a, struct list_head *b, + __attribute__((__unused__)) void *data) +{ + struct lsblk_device *ax = list_entry(a, struct lsblk_device, ls_devices), + *bx = list_entry(b, struct lsblk_device, ls_devices); + + return cmp_numbers(makedev(ax->maj, ax->min), + makedev(bx->maj, bx->min)); +} + +/* Note that dev->dedupkey has to be already set */ +int lsblk_devtree_deduplicate_devices(struct lsblk_devtree *tr) +{ + struct lsblk_device *pattern = NULL; + struct lsblk_iter itr; + char *last = NULL; + + list_sort(&tr->devices, cmp_devices_devno, NULL); + lsblk_reset_iter(&itr, LSBLK_ITER_FORWARD); + + while (lsblk_devtree_next_device(tr, &itr, &pattern) == 0) { + if (!pattern->dedupkey) + continue; + if (device_is_partition(pattern) && + pattern->wholedisk->dedupkey && + strcmp(pattern->dedupkey, pattern->wholedisk->dedupkey) == 0) + continue; + if (last && strcmp(pattern->dedupkey, last) == 0) + continue; + + devtree_dedup(tr, pattern); + last = pattern->dedupkey; + } + return 0; +} |