Signed-off-by: Sascha Hauer <[email protected]>
---
 commands/devinfo.c         |   7 ++-
 common/partitions.c        |   2 +-
 drivers/block/dm/dm-core.c |   1 -
 fs/devfs-core.c            | 148 +++++++++++++++++++--------------------------
 include/block.h            |   2 -
 include/driver.h           |   8 +--
 6 files changed, 71 insertions(+), 97 deletions(-)

diff --git a/commands/devinfo.c b/commands/devinfo.c
index 
c87b30e84307e5053bc35e8bd70ac7af63f688b8..d898e81b3278808a7eed5116d210020d8715a09f
 100644
--- a/commands/devinfo.c
+++ b/commands/devinfo.c
@@ -9,7 +9,8 @@
 static int do_devinfo_subtree(struct device *dev, int depth)
 {
        struct device *child;
-       struct cdev *cdev, *cdevl;
+       struct cdev *cdev;
+       struct string_list *sl;
        int i;
 
        for (i = 0; i < depth; i++)
@@ -26,8 +27,8 @@ static int do_devinfo_subtree(struct device *dev, int depth)
                                        cdev->offset + cdev->size - 1,
                                        size_human_readable(cdev->size),
                                        cdev->name);
-                       list_for_each_entry(cdevl, &cdev->links, link_entry)
-                               printf(", %s", cdevl->name);
+                       string_list_for_each_entry(sl, &cdev->aliases)
+                               printf(", %s", sl->str);
                        printf("\n");
                }
        } else {
diff --git a/common/partitions.c b/common/partitions.c
index 
7563cb0e6767891ee7f1fe264ce86703408f790a..1a4e046c5f55314ccb2abf5094b0966def8c5b55
 100644
--- a/common/partitions.c
+++ b/common/partitions.c
@@ -63,7 +63,7 @@ static int register_one_partition(struct block_device *blk, 
struct partition *pa
                return 0;
 
        partition_name = xasprintf("%s.%s", blk->cdev.name, part->name);
-       ret = devfs_create_link(cdev, partition_name);
+       ret = devfs_add_alias(cdev, partition_name);
        if (ret)
                dev_warn(blk->dev, "Failed to create link from %s to %s\n",
                         partition_name, cdev->name);
diff --git a/drivers/block/dm/dm-core.c b/drivers/block/dm/dm-core.c
index 
fd7ed0d84ed7388f8c1cd4aa19e0466191459fd6..2f48cfeb06f7b2da6d26850820f228a6f522fc2f
 100644
--- a/drivers/block/dm/dm-core.c
+++ b/drivers/block/dm/dm-core.c
@@ -77,7 +77,6 @@ int dm_cdev_open(struct dm_cdev *dmcdev, const char *path, 
ulong flags,
                        return -ENODEV;
                }
 
-               dmcdev->cdev = cdev_readlink(dmcdev->cdev);
                break;
        default:
                *errmsg = xstrdup("Only regular files and device specials are 
supported");
diff --git a/fs/devfs-core.c b/fs/devfs-core.c
index 
c4ff5fe5718ea2c0236fdbf124e56a13e17702d1..32e9b5f867ed1d1696a4c16fb154474f933de342
 100644
--- a/fs/devfs-core.c
+++ b/fs/devfs-core.c
@@ -50,42 +50,21 @@ int devfs_partition_complete(struct string_list *sl, char 
*instr)
 }
 #endif
 
-struct cdev *cdev_readlink(const struct cdev *cdev)
-{
-       if (!cdev)
-               return NULL;
-
-       if (cdev->link)
-               cdev = cdev->link;
-
-       /* links to links are not allowed */
-       BUG_ON(cdev->link);
-
-       return (void *)cdev;
-}
-
-struct cdev *lcdev_by_name(const char *filename)
+struct cdev *cdev_by_name(const char *filename)
 {
        struct cdev *cdev;
+       struct string_list *entry;
 
        for_each_cdev(cdev) {
                if (!strcmp(cdev->name, filename))
                        return cdev;
+               string_list_for_each_entry(entry, &cdev->aliases)
+                       if (!strcmp(entry->str, filename))
+                               return cdev;
        }
        return NULL;
 }
 
-struct cdev *cdev_by_name(const char *filename)
-{
-       struct cdev *cdev;
-
-       cdev = lcdev_by_name(filename);
-       if (!cdev)
-               return NULL;
-
-       return cdev_readlink(cdev);
-}
-
 struct cdev *cdev_by_device_node(struct device_node *node)
 {
        struct cdev *cdev;
@@ -95,7 +74,7 @@ struct cdev *cdev_by_device_node(struct device_node *node)
 
        for_each_cdev(cdev) {
                if (cdev_of_node(cdev) == node)
-                       return cdev_readlink(cdev);
+                       return cdev;
        }
        return NULL;
 }
@@ -133,9 +112,6 @@ cdev_find_child_by_gpt_typeuuid(struct cdev *cdev, const 
guid_t *typeuuid)
 {
        struct cdev *partcdev;
 
-        /* Follow links to support storage-by-alias */
-        cdev = cdev_readlink(cdev);
-
        if (!cdev_is_gpt_partitioned(cdev))
                return ERR_PTR(-EINVAL);
 
@@ -153,6 +129,29 @@ cdev_find_child_by_gpt_typeuuid(struct cdev *cdev, const 
guid_t *typeuuid)
        return ERR_PTR(-ENOENT);
 }
 
+static bool cdev_has_partname_alias(struct cdev *cdev, const char *partname)
+{
+       char *fullname;
+       struct string_list *sl;
+       bool ret = false;
+
+       if (!cdev->master)
+               return false;
+
+       fullname = xasprintf("%s.%s", cdev->master->name, partname);
+
+       string_list_for_each_entry(sl, &cdev->aliases) {
+               if (streq_ptr(sl->str, fullname)) {
+                       ret = true;
+                       break;
+               }
+       }
+
+       free(fullname);
+
+       return ret;
+}
+
 /**
  * cdev_find_partition - find a partition belonging to a physical device
  *
@@ -164,15 +163,10 @@ struct cdev *cdev_find_partition(struct cdev *cdevm, 
const char *name)
        struct cdev *partcdev;
 
        for_each_cdev_partition(partcdev, cdevm) {
-               struct cdev *cdevl;
-
                if (streq_ptr(partcdev->partname, name))
                        return partcdev;
-
-               list_for_each_entry(cdevl, &partcdev->links, link_entry) {
-                       if (streq_ptr(cdevl->partname, name))
-                               return cdevl;
-               }
+               if (cdev_has_partname_alias(partcdev, name))
+                       return partcdev;
        }
 
        return NULL;
@@ -190,15 +184,11 @@ struct cdev *device_find_partition(struct device *dev, 
const char *name)
        struct device *child;
 
        list_for_each_entry(cdev, &dev->cdevs, devices_list) {
-               struct cdev *cdevl;
-
                if (streq_ptr(cdev->partname, name))
                        return cdev;
 
-               list_for_each_entry(cdevl, &cdev->links, link_entry) {
-                       if (streq_ptr(cdevl->partname, name))
-                               return cdev_readlink(cdevl);
-               }
+               if (cdev_has_partname_alias(cdev, name))
+                       return cdev;
        }
 
        device_for_each_child(dev, child) {
@@ -460,20 +450,36 @@ static void cdev_free(struct cdev *cdev)
 
 static bool devfs_initialized;
 
+static int cdev_symlink(struct cdev *cdev, const char *linkname)
+{
+       char *path;
+       int ret;
+
+       if (!devfs_initialized)
+               return 0;
+
+       path = xasprintf("/dev/%s", linkname);
+       ret = symlink(cdev->name, path);
+       free(path);
+
+       return ret;
+}
+
 static void devfs_mknod(struct cdev *cdev)
 {
        char *path;
        int ret;
+       struct string_list *sl;
 
        if (!devfs_initialized)
                return;
 
        path = xasprintf("/dev/%s", cdev->name);
 
-       if (cdev->link)
-               ret = symlink(cdev->link->name, path);
-       else
-               ret = mknod(path, S_IFCHR | 0600, cdev->name);
+       string_list_for_each_entry(sl, &cdev->aliases)
+               cdev_symlink(cdev, sl->str);
+
+       ret = mknod(path, S_IFCHR | 0600, cdev->name);
 
        free(path);
 
@@ -499,8 +505,8 @@ int devfs_create(struct cdev *new)
        if (cdev)
                return -EEXIST;
 
-       INIT_LIST_HEAD(&new->links);
        INIT_LIST_HEAD(&new->partitions);
+       string_list_init(&new->aliases);
 
        list_add_tail(&new->list, &cdev_list);
        if (new->dev) {
@@ -509,46 +515,22 @@ int devfs_create(struct cdev *new)
                        new->device_node = new->dev->of_node;
        }
 
-       if (new->link)
-               list_add_tail(&new->link_entry, &new->link->links);
-
        devfs_mknod(new);
 
        return 0;
 }
 
-int devfs_create_link(struct cdev *cdev, const char *name)
+int devfs_add_alias(struct cdev *cdev, const char *name)
 {
-       struct cdev *new;
-       int ret;
-
-       /*
-        * Create a link to the real cdev instead of creating
-        * a link to a link.
-        */
-       cdev = cdev_readlink(cdev);
-
-       new = cdev_alloc(name);
-       new->link = cdev;
+       struct cdev *conflict;
 
-       ret = devfs_create(new);
-       if (ret) {
-               cdev_free(new);
-               return ret;
-       }
-
-       if (cdev->partname) {
-               size_t partnameoff = 0;
-
-               if (cdev->master) {
-                       size_t masterlen = strlen(cdev->master->name);
+       conflict = cdev_by_name(name);
+       if (conflict)
+               return -EEXIST;
 
-                       if (!strncmp(name, cdev->master->name, masterlen))
-                               partnameoff += masterlen + 1;
-               }
+       string_list_add(&cdev->aliases, name);
 
-               new->partname = xstrdup(name + partnameoff);
-       }
+       cdev_symlink(cdev, name);
 
        return 0;
 }
@@ -565,8 +547,7 @@ int devfs_remove(struct cdev *cdev)
        if (cdev->dev)
                list_del(&cdev->devices_list);
 
-       list_for_each_entry_safe(c, tmp, &cdev->links, link_entry)
-               devfs_remove(c);
+       string_list_free(&cdev->aliases);
 
        list_for_each_entry_safe(c, tmp, &cdev->partitions, partition_entry)
                cdevfs_del_partition(c);
@@ -574,9 +555,6 @@ int devfs_remove(struct cdev *cdev)
        if (cdev_is_partition(cdev))
                list_del(&cdev->partition_entry);
 
-       if (cdev->link)
-               cdev_free(cdev);
-
        return 0;
 }
 
@@ -681,7 +659,7 @@ static struct cdev *__devfs_add_partition(struct cdev *cdev,
        if (overlap) {
                if (!IS_ERR(overlap)) {
                        /* only fails with -EEXIST, which is fine */
-                       (void)devfs_create_link(overlap, partinfo->name);
+                       (void)devfs_add_alias(overlap, partinfo->name);
                }
 
                return overlap;
diff --git a/include/block.h b/include/block.h
index 
fc7a0a32fb2d6bc579aa6305433fb2a9e39f336a..a8ebe202288fff83677948f3d67bc12cae5dc107
 100644
--- a/include/block.h
+++ b/include/block.h
@@ -104,13 +104,11 @@ static inline bool cdev_is_block_device(const struct cdev 
*cdev)
 
 static inline bool cdev_is_block_partition(const struct cdev *cdev)
 {
-       cdev = cdev_readlink(cdev);
        return cdev_is_block_device(cdev) && cdev_is_partition(cdev);
 }
 
 static inline bool cdev_is_block_disk(const struct cdev *cdev)
 {
-       cdev = cdev_readlink(cdev);
        return cdev_is_block_device(cdev) && !cdev_is_partition(cdev);
 }
 
diff --git a/include/driver.h b/include/driver.h
index 
5a67d20ccff3fca339e7b40c32ecfbc244f358f5..afd22b88e5116c73bd79fc650fee9cbf6acfe247
 100644
--- a/include/driver.h
+++ b/include/driver.h
@@ -17,6 +17,7 @@
 #include <init.h>
 #include <errno.h>
 #include <filetype.h>
+#include <stringlist.h>
 
 #define FORMAT_DRIVER_NAME_ID  "%s%d"
 
@@ -432,8 +433,7 @@ struct cdev {
        u16 typeflags; /* GPT type-specific attributes */
        int open;
        struct mtd_info *mtd;
-       struct cdev *link;
-       struct list_head link_entry, links;
+       struct string_list aliases;
        struct list_head partition_entry, partitions;
        struct cdev *master;
        enum filetype filetype;
@@ -461,13 +461,11 @@ static inline const char *cdev_name(struct cdev *cdev)
 
 void devfs_init(void);
 int devfs_create(struct cdev *);
-int devfs_create_link(struct cdev *, const char *name);
+int devfs_add_alias(struct cdev *, const char *name);
 int devfs_remove(struct cdev *);
 int cdev_find_free_index(const char *);
 struct cdev *cdev_find_partition(struct cdev *cdevm, const char *name);
 struct cdev *device_find_partition(struct device *dev, const char *name);
-struct cdev *lcdev_by_name(const char *filename);
-struct cdev *cdev_readlink(const struct cdev *cdev);
 struct cdev *cdev_by_device_node(struct device_node *node);
 struct cdev *cdev_by_partuuid(const char *partuuid);
 struct cdev *cdev_by_diskuuid(const char *partuuid);

-- 
2.47.3


Reply via email to