diff options
author | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2010-01-12 05:26:42 -0500 |
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committer | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2010-02-01 08:16:36 -0500 |
commit | 0bf1c4399afee6a2031b0ee943a4c016e53f727c (patch) | |
tree | c5d7a62b2c965e65a42f17f6206c28f3c4e57a81 /drivers/mtd/ubi | |
parent | f9b0080e10e0ce3b8acbe91ae6a50da4f2ed7339 (diff) |
UBI: fix attaching error path
In the error path of 'ubi_attach_mtd_dev()' we have a tricky situation:
we have to release things differently depending on at which point
the failure happening. Namely, if @ubi->dev is not initialized, we have
to free everything ourselves. But if it was, we should not free the @ubi
object, because it will be freed in the 'dev_release()' function. And
we did not get this situation right.
This patch introduces additional argument to the 'uif_init()' function.
On exit, this argument indicates whether the final 'free(ubi)' will
happen in 'dev_release()' or not. So the caller always knows how to
properly release the resources.
Impact: all memory is now correctly released when UBI fails to attach
an MTD device.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Diffstat (limited to 'drivers/mtd/ubi')
-rw-r--r-- | drivers/mtd/ubi/build.c | 63 |
1 files changed, 30 insertions, 33 deletions
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 99ff57d3ac68..bc45ef9af17d 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c | |||
@@ -365,11 +365,13 @@ static void dev_release(struct device *dev) | |||
365 | /** | 365 | /** |
366 | * ubi_sysfs_init - initialize sysfs for an UBI device. | 366 | * ubi_sysfs_init - initialize sysfs for an UBI device. |
367 | * @ubi: UBI device description object | 367 | * @ubi: UBI device description object |
368 | * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was | ||
369 | * taken | ||
368 | * | 370 | * |
369 | * This function returns zero in case of success and a negative error code in | 371 | * This function returns zero in case of success and a negative error code in |
370 | * case of failure. | 372 | * case of failure. |
371 | */ | 373 | */ |
372 | static int ubi_sysfs_init(struct ubi_device *ubi) | 374 | static int ubi_sysfs_init(struct ubi_device *ubi, int *ref) |
373 | { | 375 | { |
374 | int err; | 376 | int err; |
375 | 377 | ||
@@ -381,6 +383,7 @@ static int ubi_sysfs_init(struct ubi_device *ubi) | |||
381 | if (err) | 383 | if (err) |
382 | return err; | 384 | return err; |
383 | 385 | ||
386 | *ref = 1; | ||
384 | err = device_create_file(&ubi->dev, &dev_eraseblock_size); | 387 | err = device_create_file(&ubi->dev, &dev_eraseblock_size); |
385 | if (err) | 388 | if (err) |
386 | return err; | 389 | return err; |
@@ -436,7 +439,7 @@ static void ubi_sysfs_close(struct ubi_device *ubi) | |||
436 | } | 439 | } |
437 | 440 | ||
438 | /** | 441 | /** |
439 | * kill_volumes - destroy all volumes. | 442 | * kill_volumes - destroy all user volumes. |
440 | * @ubi: UBI device description object | 443 | * @ubi: UBI device description object |
441 | */ | 444 | */ |
442 | static void kill_volumes(struct ubi_device *ubi) | 445 | static void kill_volumes(struct ubi_device *ubi) |
@@ -449,36 +452,29 @@ static void kill_volumes(struct ubi_device *ubi) | |||
449 | } | 452 | } |
450 | 453 | ||
451 | /** | 454 | /** |
452 | * free_user_volumes - free all user volumes. | ||
453 | * @ubi: UBI device description object | ||
454 | * | ||
455 | * Normally the volumes are freed at the release function of the volume device | ||
456 | * objects. However, on error paths the volumes have to be freed before the | ||
457 | * device objects have been initialized. | ||
458 | */ | ||
459 | static void free_user_volumes(struct ubi_device *ubi) | ||
460 | { | ||
461 | int i; | ||
462 | |||
463 | for (i = 0; i < ubi->vtbl_slots; i++) | ||
464 | if (ubi->volumes[i]) { | ||
465 | kfree(ubi->volumes[i]->eba_tbl); | ||
466 | kfree(ubi->volumes[i]); | ||
467 | } | ||
468 | } | ||
469 | |||
470 | /** | ||
471 | * uif_init - initialize user interfaces for an UBI device. | 455 | * uif_init - initialize user interfaces for an UBI device. |
472 | * @ubi: UBI device description object | 456 | * @ubi: UBI device description object |
457 | * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was | ||
458 | * taken, otherwise set to %0 | ||
459 | * | ||
460 | * This function initializes various user interfaces for an UBI device. If the | ||
461 | * initialization fails at an early stage, this function frees all the | ||
462 | * resources it allocated, returns an error, and @ref is set to %0. However, | ||
463 | * if the initialization fails after the UBI device was registered in the | ||
464 | * driver core subsystem, this function takes a reference to @ubi->dev, because | ||
465 | * otherwise the release function ('dev_release()') would free whole @ubi | ||
466 | * object. The @ref argument is set to %1 in this case. The caller has to put | ||
467 | * this reference. | ||
473 | * | 468 | * |
474 | * This function returns zero in case of success and a negative error code in | 469 | * This function returns zero in case of success and a negative error code in |
475 | * case of failure. Note, this function destroys all volumes if it fails. | 470 | * case of failure. |
476 | */ | 471 | */ |
477 | static int uif_init(struct ubi_device *ubi) | 472 | static int uif_init(struct ubi_device *ubi, int *ref) |
478 | { | 473 | { |
479 | int i, err; | 474 | int i, err; |
480 | dev_t dev; | 475 | dev_t dev; |
481 | 476 | ||
477 | *ref = 0; | ||
482 | sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num); | 478 | sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num); |
483 | 479 | ||
484 | /* | 480 | /* |
@@ -506,7 +502,7 @@ static int uif_init(struct ubi_device *ubi) | |||
506 | goto out_unreg; | 502 | goto out_unreg; |
507 | } | 503 | } |
508 | 504 | ||
509 | err = ubi_sysfs_init(ubi); | 505 | err = ubi_sysfs_init(ubi, ref); |
510 | if (err) | 506 | if (err) |
511 | goto out_sysfs; | 507 | goto out_sysfs; |
512 | 508 | ||
@@ -524,6 +520,8 @@ static int uif_init(struct ubi_device *ubi) | |||
524 | out_volumes: | 520 | out_volumes: |
525 | kill_volumes(ubi); | 521 | kill_volumes(ubi); |
526 | out_sysfs: | 522 | out_sysfs: |
523 | if (*ref) | ||
524 | get_device(&ubi->dev); | ||
527 | ubi_sysfs_close(ubi); | 525 | ubi_sysfs_close(ubi); |
528 | cdev_del(&ubi->cdev); | 526 | cdev_del(&ubi->cdev); |
529 | out_unreg: | 527 | out_unreg: |
@@ -877,7 +875,7 @@ static int ubi_reboot_notifier(struct notifier_block *n, unsigned long state, | |||
877 | int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) | 875 | int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) |
878 | { | 876 | { |
879 | struct ubi_device *ubi; | 877 | struct ubi_device *ubi; |
880 | int i, err, do_free = 1; | 878 | int i, err, ref = 0; |
881 | 879 | ||
882 | /* | 880 | /* |
883 | * Check if we already have the same MTD device attached. | 881 | * Check if we already have the same MTD device attached. |
@@ -977,9 +975,9 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) | |||
977 | goto out_detach; | 975 | goto out_detach; |
978 | } | 976 | } |
979 | 977 | ||
980 | err = uif_init(ubi); | 978 | err = uif_init(ubi, &ref); |
981 | if (err) | 979 | if (err) |
982 | goto out_nofree; | 980 | goto out_detach; |
983 | 981 | ||
984 | ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name); | 982 | ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name); |
985 | if (IS_ERR(ubi->bgt_thread)) { | 983 | if (IS_ERR(ubi->bgt_thread)) { |
@@ -1027,12 +1025,8 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) | |||
1027 | 1025 | ||
1028 | out_uif: | 1026 | out_uif: |
1029 | uif_close(ubi); | 1027 | uif_close(ubi); |
1030 | out_nofree: | ||
1031 | do_free = 0; | ||
1032 | out_detach: | 1028 | out_detach: |
1033 | ubi_wl_close(ubi); | 1029 | ubi_wl_close(ubi); |
1034 | if (do_free) | ||
1035 | free_user_volumes(ubi); | ||
1036 | free_internal_volumes(ubi); | 1030 | free_internal_volumes(ubi); |
1037 | vfree(ubi->vtbl); | 1031 | vfree(ubi->vtbl); |
1038 | out_free: | 1032 | out_free: |
@@ -1041,7 +1035,10 @@ out_free: | |||
1041 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | 1035 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID |
1042 | vfree(ubi->dbg_peb_buf); | 1036 | vfree(ubi->dbg_peb_buf); |
1043 | #endif | 1037 | #endif |
1044 | kfree(ubi); | 1038 | if (ref) |
1039 | put_device(&ubi->dev); | ||
1040 | else | ||
1041 | kfree(ubi); | ||
1045 | return err; | 1042 | return err; |
1046 | } | 1043 | } |
1047 | 1044 | ||
@@ -1098,7 +1095,7 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway) | |||
1098 | 1095 | ||
1099 | /* | 1096 | /* |
1100 | * Get a reference to the device in order to prevent 'dev_release()' | 1097 | * Get a reference to the device in order to prevent 'dev_release()' |
1101 | * from freeing @ubi object. | 1098 | * from freeing the @ubi object. |
1102 | */ | 1099 | */ |
1103 | get_device(&ubi->dev); | 1100 | get_device(&ubi->dev); |
1104 | 1101 | ||