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-rw-r--r--include/mtd/ubi-user.h208
1 files changed, 175 insertions, 33 deletions
diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h
index a7421f1..296efae 100644
--- a/include/mtd/ubi-user.h
+++ b/include/mtd/ubi-user.h
@@ -40,30 +40,37 @@
* UBI volume creation
* ~~~~~~~~~~~~~~~~~~~
*
- * UBI volumes are created via the %UBI_IOCMKVOL IOCTL command of UBI character
+ * UBI volumes are created via the %UBI_IOCMKVOL ioctl command of UBI character
* device. A &struct ubi_mkvol_req object has to be properly filled and a
- * pointer to it has to be passed to the IOCTL.
+ * pointer to it has to be passed to the ioctl.
*
* UBI volume deletion
* ~~~~~~~~~~~~~~~~~~~
*
- * To delete a volume, the %UBI_IOCRMVOL IOCTL command of the UBI character
+ * To delete a volume, the %UBI_IOCRMVOL ioctl command of the UBI character
* device should be used. A pointer to the 32-bit volume ID hast to be passed
- * to the IOCTL.
+ * to the ioctl.
*
* UBI volume re-size
* ~~~~~~~~~~~~~~~~~~
*
- * To re-size a volume, the %UBI_IOCRSVOL IOCTL command of the UBI character
+ * To re-size a volume, the %UBI_IOCRSVOL ioctl command of the UBI character
* device should be used. A &struct ubi_rsvol_req object has to be properly
- * filled and a pointer to it has to be passed to the IOCTL.
+ * filled and a pointer to it has to be passed to the ioctl.
+ *
+ * UBI volumes re-name
+ * ~~~~~~~~~~~~~~~~~~~
+ *
+ * To re-name several volumes atomically at one go, the %UBI_IOCRNVOL command
+ * of the UBI character device should be used. A &struct ubi_rnvol_req object
+ * has to be properly filled and a pointer to it has to be passed to the ioctl.
*
* UBI volume update
* ~~~~~~~~~~~~~~~~~
*
- * Volume update should be done via the %UBI_IOCVOLUP IOCTL command of the
+ * Volume update should be done via the %UBI_IOCVOLUP ioctl command of the
* corresponding UBI volume character device. A pointer to a 64-bit update
- * size should be passed to the IOCTL. After this, UBI expects user to write
+ * size should be passed to the ioctl. After this, UBI expects user to write
* this number of bytes to the volume character device. The update is finished
* when the claimed number of bytes is passed. So, the volume update sequence
* is something like:
@@ -73,14 +80,58 @@
* write(fd, buf, image_size);
* close(fd);
*
- * Atomic eraseblock change
+ * Logical eraseblock erase
* ~~~~~~~~~~~~~~~~~~~~~~~~
*
- * Atomic eraseblock change operation is done via the %UBI_IOCEBCH IOCTL
- * command of the corresponding UBI volume character device. A pointer to
- * &struct ubi_leb_change_req has to be passed to the IOCTL. Then the user is
- * expected to write the requested amount of bytes. This is similar to the
- * "volume update" IOCTL.
+ * To erase a logical eraseblock, the %UBI_IOCEBER ioctl command of the
+ * corresponding UBI volume character device should be used. This command
+ * unmaps the requested logical eraseblock, makes sure the corresponding
+ * physical eraseblock is successfully erased, and returns.
+ *
+ * Atomic logical eraseblock change
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * Atomic logical eraseblock change operation is called using the %UBI_IOCEBCH
+ * ioctl command of the corresponding UBI volume character device. A pointer to
+ * a &struct ubi_leb_change_req object has to be passed to the ioctl. Then the
+ * user is expected to write the requested amount of bytes (similarly to what
+ * should be done in case of the "volume update" ioctl).
+ *
+ * Logical eraseblock map
+ * ~~~~~~~~~~~~~~~~~~~~~
+ *
+ * To map a logical eraseblock to a physical eraseblock, the %UBI_IOCEBMAP
+ * ioctl command should be used. A pointer to a &struct ubi_map_req object is
+ * expected to be passed. The ioctl maps the requested logical eraseblock to
+ * a physical eraseblock and returns. Only non-mapped logical eraseblocks can
+ * be mapped. If the logical eraseblock specified in the request is already
+ * mapped to a physical eraseblock, the ioctl fails and returns error.
+ *
+ * Logical eraseblock unmap
+ * ~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * To unmap a logical eraseblock to a physical eraseblock, the %UBI_IOCEBUNMAP
+ * ioctl command should be used. The ioctl unmaps the logical eraseblocks,
+ * schedules corresponding physical eraseblock for erasure, and returns. Unlike
+ * the "LEB erase" command, it does not wait for the physical eraseblock being
+ * erased. Note, the side effect of this is that if an unclean reboot happens
+ * after the unmap ioctl returns, you may find the LEB mapped again to the same
+ * physical eraseblock after the UBI is run again.
+ *
+ * Check if logical eraseblock is mapped
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * To check if a logical eraseblock is mapped to a physical eraseblock, the
+ * %UBI_IOCEBISMAP ioctl command should be used. It returns %0 if the LEB is
+ * not mapped, and %1 if it is mapped.
+ *
+ * Set an UBI volume property
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * To set an UBI volume property the %UBI_IOCSETPROP ioctl command should be
+ * used. A pointer to a &struct ubi_set_prop_req object is expected to be
+ * passed. The object describes which property should be set, and to which value
+ * it should be set.
*/
/*
@@ -94,7 +145,7 @@
/* Maximum volume name length */
#define UBI_MAX_VOLUME_NAME 127
-/* IOCTL commands of UBI character devices */
+/* ioctl commands of UBI character devices */
#define UBI_IOC_MAGIC 'o'
@@ -104,8 +155,10 @@
#define UBI_IOCRMVOL _IOW(UBI_IOC_MAGIC, 1, int32_t)
/* Re-size an UBI volume */
#define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req)
+/* Re-name volumes */
+#define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req)
-/* IOCTL commands of the UBI control character device */
+/* ioctl commands of the UBI control character device */
#define UBI_CTRL_IOC_MAGIC 'o'
@@ -114,20 +167,31 @@
/* Detach an MTD device */
#define UBI_IOCDET _IOW(UBI_CTRL_IOC_MAGIC, 65, int32_t)
-/* IOCTL commands of UBI volume character devices */
+/* ioctl commands of UBI volume character devices */
#define UBI_VOL_IOC_MAGIC 'O'
/* Start UBI volume update */
#define UBI_IOCVOLUP _IOW(UBI_VOL_IOC_MAGIC, 0, int64_t)
-/* An eraseblock erasure command, used for debugging, disabled by default */
+/* LEB erasure command, used for debugging, disabled by default */
#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 1, int32_t)
-/* An atomic eraseblock change command */
+/* Atomic LEB change command */
#define UBI_IOCEBCH _IOW(UBI_VOL_IOC_MAGIC, 2, int32_t)
+/* Map LEB command */
+#define UBI_IOCEBMAP _IOW(UBI_VOL_IOC_MAGIC, 3, struct ubi_map_req)
+/* Unmap LEB command */
+#define UBI_IOCEBUNMAP _IOW(UBI_VOL_IOC_MAGIC, 4, int32_t)
+/* Check if LEB is mapped command */
+#define UBI_IOCEBISMAP _IOR(UBI_VOL_IOC_MAGIC, 5, int32_t)
+/* Set an UBI volume property */
+#define UBI_IOCSETPROP _IOW(UBI_VOL_IOC_MAGIC, 6, struct ubi_set_prop_req)
/* Maximum MTD device name length supported by UBI */
#define MAX_UBI_MTD_NAME_LEN 127
+/* Maximum amount of UBI volumes that can be re-named at one go */
+#define UBI_MAX_RNVOL 32
+
/*
* UBI data type hint constants.
*
@@ -156,6 +220,16 @@ enum {
UBI_STATIC_VOLUME = 4,
};
+/*
+ * UBI set property ioctl constants
+ *
+ * @UBI_PROP_DIRECT_WRITE: allow / disallow user to directly write and
+ * erase individual eraseblocks on dynamic volumes
+ */
+enum {
+ UBI_PROP_DIRECT_WRITE = 1,
+};
+
/**
* struct ubi_attach_req - attach MTD device request.
* @ubi_num: UBI device number to create
@@ -176,20 +250,20 @@ enum {
* it will be 512 in case of a 2KiB page NAND flash with 4 512-byte sub-pages.
*
* But in rare cases, if this optimizes things, the VID header may be placed to
- * a different offset. For example, the boot-loader might do things faster if the
- * VID header sits at the end of the first 2KiB NAND page with 4 sub-pages. As
- * the boot-loader would not normally need to read EC headers (unless it needs
- * UBI in RW mode), it might be faster to calculate ECC. This is weird example,
- * but it real-life example. So, in this example, @vid_hdr_offer would be
- * 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes
- * aligned, which is OK, as UBI is clever enough to realize this is 4th sub-page
- * of the first page and add needed padding.
+ * a different offset. For example, the boot-loader might do things faster if
+ * the VID header sits at the end of the first 2KiB NAND page with 4 sub-pages.
+ * As the boot-loader would not normally need to read EC headers (unless it
+ * needs UBI in RW mode), it might be faster to calculate ECC. This is weird
+ * example, but it real-life example. So, in this example, @vid_hdr_offer would
+ * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes
+ * aligned, which is OK, as UBI is clever enough to realize this is 4th
+ * sub-page of the first page and add needed padding.
*/
struct ubi_attach_req {
int32_t ubi_num;
int32_t mtd_num;
int32_t vid_hdr_offset;
- uint8_t padding[12];
+ int8_t padding[12];
};
/**
@@ -241,7 +315,7 @@ struct ubi_mkvol_req {
*
* Re-sizing is possible for both dynamic and static volumes. But while dynamic
* volumes may be re-sized arbitrarily, static volumes cannot be made to be
- * smaller then the number of bytes they bear. To arbitrarily shrink a static
+ * smaller than the number of bytes they bear. To arbitrarily shrink a static
* volume, it must be wiped out first (by means of volume update operation with
* zero number of bytes).
*/
@@ -251,8 +325,50 @@ struct ubi_rsvol_req {
} __attribute__ ((packed));
/**
- * struct ubi_leb_change_req - a data structure used in atomic logical
- * eraseblock change requests.
+ * struct ubi_rnvol_req - volumes re-name request.
+ * @count: count of volumes to re-name
+ * @padding1: reserved for future, not used, has to be zeroed
+ * @vol_id: ID of the volume to re-name
+ * @name_len: name length
+ * @padding2: reserved for future, not used, has to be zeroed
+ * @name: new volume name
+ *
+ * UBI allows to re-name up to %32 volumes at one go. The count of volumes to
+ * re-name is specified in the @count field. The ID of the volumes to re-name
+ * and the new names are specified in the @vol_id and @name fields.
+ *
+ * The UBI volume re-name operation is atomic, which means that should power cut
+ * happen, the volumes will have either old name or new name. So the possible
+ * use-cases of this command is atomic upgrade. Indeed, to upgrade, say, volumes
+ * A and B one may create temporary volumes %A1 and %B1 with the new contents,
+ * then atomically re-name A1->A and B1->B, in which case old %A and %B will
+ * be removed.
+ *
+ * If it is not desirable to remove old A and B, the re-name request has to
+ * contain 4 entries: A1->A, A->A1, B1->B, B->B1, in which case old A1 and B1
+ * become A and B, and old A and B will become A1 and B1.
+ *
+ * It is also OK to request: A1->A, A1->X, B1->B, B->Y, in which case old A1
+ * and B1 become A and B, and old A and B become X and Y.
+ *
+ * In other words, in case of re-naming into an existing volume name, the
+ * existing volume is removed, unless it is re-named as well at the same
+ * re-name request.
+ */
+struct ubi_rnvol_req {
+ int32_t count;
+ int8_t padding1[12];
+ struct {
+ int32_t vol_id;
+ int16_t name_len;
+ int8_t padding2[2];
+ char name[UBI_MAX_VOLUME_NAME + 1];
+ } ents[UBI_MAX_RNVOL];
+} __attribute__ ((packed));
+
+/**
+ * struct ubi_leb_change_req - a data structure used in atomic LEB change
+ * requests.
* @lnum: logical eraseblock number to change
* @bytes: how many bytes will be written to the logical eraseblock
* @dtype: data type (%UBI_LONGTERM, %UBI_SHORTTERM, %UBI_UNKNOWN)
@@ -261,8 +377,34 @@ struct ubi_rsvol_req {
struct ubi_leb_change_req {
int32_t lnum;
int32_t bytes;
- uint8_t dtype;
- uint8_t padding[7];
+ int8_t dtype;
+ int8_t padding[7];
} __attribute__ ((packed));
+/**
+ * struct ubi_map_req - a data structure used in map LEB requests.
+ * @lnum: logical eraseblock number to unmap
+ * @dtype: data type (%UBI_LONGTERM, %UBI_SHORTTERM, %UBI_UNKNOWN)
+ * @padding: reserved for future, not used, has to be zeroed
+ */
+struct ubi_map_req {
+ int32_t lnum;
+ int8_t dtype;
+ int8_t padding[3];
+} __attribute__ ((packed));
+
+
+/**
+ * struct ubi_set_prop_req - a data structure used to set an ubi volume
+ * property.
+ * @property: property to set (%UBI_PROP_DIRECT_WRITE)
+ * @padding: reserved for future, not used, has to be zeroed
+ * @value: value to set
+ */
+struct ubi_set_prop_req {
+ uint8_t property;
+ uint8_t padding[7];
+ uint64_t value;
+} __attribute__ ((packed));
+
#endif /* __UBI_USER_H__ */