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1700 lines
46 KiB
1700 lines
46 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
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* Copyright (c) International Business Machines Corp., 2006 |
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* |
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* Author: Artem Bityutskiy (Битюцкий Артём) |
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*/ |
|
|
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/* |
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* The UBI Eraseblock Association (EBA) sub-system. |
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* |
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* This sub-system is responsible for I/O to/from logical eraseblock. |
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* |
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* Although in this implementation the EBA table is fully kept and managed in |
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* RAM, which assumes poor scalability, it might be (partially) maintained on |
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* flash in future implementations. |
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* |
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* The EBA sub-system implements per-logical eraseblock locking. Before |
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* accessing a logical eraseblock it is locked for reading or writing. The |
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* per-logical eraseblock locking is implemented by means of the lock tree. The |
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* lock tree is an RB-tree which refers all the currently locked logical |
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* eraseblocks. The lock tree elements are &struct ubi_ltree_entry objects. |
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* They are indexed by (@vol_id, @lnum) pairs. |
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* |
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* EBA also maintains the global sequence counter which is incremented each |
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* time a logical eraseblock is mapped to a physical eraseblock and it is |
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* stored in the volume identifier header. This means that each VID header has |
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* a unique sequence number. The sequence number is only increased an we assume |
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* 64 bits is enough to never overflow. |
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*/ |
|
|
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#include <linux/slab.h> |
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#include <linux/crc32.h> |
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#include <linux/err.h> |
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#include "ubi.h" |
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|
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/* Number of physical eraseblocks reserved for atomic LEB change operation */ |
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#define EBA_RESERVED_PEBS 1 |
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|
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/** |
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* struct ubi_eba_entry - structure encoding a single LEB -> PEB association |
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* @pnum: the physical eraseblock number attached to the LEB |
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* |
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* This structure is encoding a LEB -> PEB association. Note that the LEB |
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* number is not stored here, because it is the index used to access the |
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* entries table. |
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*/ |
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struct ubi_eba_entry { |
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int pnum; |
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}; |
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|
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/** |
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* struct ubi_eba_table - LEB -> PEB association information |
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* @entries: the LEB to PEB mapping (one entry per LEB). |
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* |
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* This structure is private to the EBA logic and should be kept here. |
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* It is encoding the LEB to PEB association table, and is subject to |
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* changes. |
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*/ |
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struct ubi_eba_table { |
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struct ubi_eba_entry *entries; |
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}; |
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|
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/** |
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* next_sqnum - get next sequence number. |
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* @ubi: UBI device description object |
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* |
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* This function returns next sequence number to use, which is just the current |
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* global sequence counter value. It also increases the global sequence |
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* counter. |
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*/ |
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unsigned long long ubi_next_sqnum(struct ubi_device *ubi) |
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{ |
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unsigned long long sqnum; |
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|
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spin_lock(&ubi->ltree_lock); |
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sqnum = ubi->global_sqnum++; |
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spin_unlock(&ubi->ltree_lock); |
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|
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return sqnum; |
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} |
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|
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/** |
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* ubi_get_compat - get compatibility flags of a volume. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* |
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* This function returns compatibility flags for an internal volume. User |
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* volumes have no compatibility flags, so %0 is returned. |
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*/ |
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static int ubi_get_compat(const struct ubi_device *ubi, int vol_id) |
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{ |
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if (vol_id == UBI_LAYOUT_VOLUME_ID) |
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return UBI_LAYOUT_VOLUME_COMPAT; |
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return 0; |
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} |
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|
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/** |
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* ubi_eba_get_ldesc - get information about a LEB |
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* @vol: volume description object |
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* @lnum: logical eraseblock number |
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* @ldesc: the LEB descriptor to fill |
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* |
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* Used to query information about a specific LEB. |
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* It is currently only returning the physical position of the LEB, but will be |
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* extended to provide more information. |
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*/ |
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void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum, |
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struct ubi_eba_leb_desc *ldesc) |
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{ |
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ldesc->lnum = lnum; |
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ldesc->pnum = vol->eba_tbl->entries[lnum].pnum; |
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} |
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|
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/** |
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* ubi_eba_create_table - allocate a new EBA table and initialize it with all |
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* LEBs unmapped |
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* @vol: volume containing the EBA table to copy |
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* @nentries: number of entries in the table |
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* |
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* Allocate a new EBA table and initialize it with all LEBs unmapped. |
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* Returns a valid pointer if it succeed, an ERR_PTR() otherwise. |
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*/ |
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struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol, |
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int nentries) |
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{ |
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struct ubi_eba_table *tbl; |
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int err = -ENOMEM; |
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int i; |
|
|
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tbl = kzalloc(sizeof(*tbl), GFP_KERNEL); |
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if (!tbl) |
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return ERR_PTR(-ENOMEM); |
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|
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tbl->entries = kmalloc_array(nentries, sizeof(*tbl->entries), |
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GFP_KERNEL); |
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if (!tbl->entries) |
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goto err; |
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|
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for (i = 0; i < nentries; i++) |
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tbl->entries[i].pnum = UBI_LEB_UNMAPPED; |
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|
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return tbl; |
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|
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err: |
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kfree(tbl); |
|
|
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return ERR_PTR(err); |
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} |
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|
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/** |
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* ubi_eba_destroy_table - destroy an EBA table |
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* @tbl: the table to destroy |
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* |
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* Destroy an EBA table. |
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*/ |
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void ubi_eba_destroy_table(struct ubi_eba_table *tbl) |
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{ |
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if (!tbl) |
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return; |
|
|
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kfree(tbl->entries); |
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kfree(tbl); |
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} |
|
|
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/** |
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* ubi_eba_copy_table - copy the EBA table attached to vol into another table |
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* @vol: volume containing the EBA table to copy |
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* @dst: destination |
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* @nentries: number of entries to copy |
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* |
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* Copy the EBA table stored in vol into the one pointed by dst. |
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*/ |
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void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst, |
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int nentries) |
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{ |
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struct ubi_eba_table *src; |
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int i; |
|
|
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ubi_assert(dst && vol && vol->eba_tbl); |
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|
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src = vol->eba_tbl; |
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|
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for (i = 0; i < nentries; i++) |
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dst->entries[i].pnum = src->entries[i].pnum; |
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} |
|
|
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/** |
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* ubi_eba_replace_table - assign a new EBA table to a volume |
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* @vol: volume containing the EBA table to copy |
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* @tbl: new EBA table |
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* |
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* Assign a new EBA table to the volume and release the old one. |
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*/ |
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void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl) |
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{ |
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ubi_eba_destroy_table(vol->eba_tbl); |
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vol->eba_tbl = tbl; |
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} |
|
|
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/** |
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* ltree_lookup - look up the lock tree. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* @lnum: logical eraseblock number |
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* |
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* This function returns a pointer to the corresponding &struct ubi_ltree_entry |
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* object if the logical eraseblock is locked and %NULL if it is not. |
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* @ubi->ltree_lock has to be locked. |
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*/ |
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static struct ubi_ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id, |
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int lnum) |
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{ |
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struct rb_node *p; |
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|
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p = ubi->ltree.rb_node; |
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while (p) { |
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struct ubi_ltree_entry *le; |
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|
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le = rb_entry(p, struct ubi_ltree_entry, rb); |
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|
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if (vol_id < le->vol_id) |
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p = p->rb_left; |
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else if (vol_id > le->vol_id) |
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p = p->rb_right; |
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else { |
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if (lnum < le->lnum) |
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p = p->rb_left; |
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else if (lnum > le->lnum) |
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p = p->rb_right; |
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else |
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return le; |
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} |
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} |
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|
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return NULL; |
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} |
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|
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/** |
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* ltree_add_entry - add new entry to the lock tree. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* @lnum: logical eraseblock number |
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* |
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* This function adds new entry for logical eraseblock (@vol_id, @lnum) to the |
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* lock tree. If such entry is already there, its usage counter is increased. |
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* Returns pointer to the lock tree entry or %-ENOMEM if memory allocation |
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* failed. |
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*/ |
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static struct ubi_ltree_entry *ltree_add_entry(struct ubi_device *ubi, |
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int vol_id, int lnum) |
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{ |
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struct ubi_ltree_entry *le, *le1, *le_free; |
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|
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le = kmalloc(sizeof(struct ubi_ltree_entry), GFP_NOFS); |
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if (!le) |
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return ERR_PTR(-ENOMEM); |
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|
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le->users = 0; |
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init_rwsem(&le->mutex); |
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le->vol_id = vol_id; |
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le->lnum = lnum; |
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|
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spin_lock(&ubi->ltree_lock); |
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le1 = ltree_lookup(ubi, vol_id, lnum); |
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|
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if (le1) { |
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/* |
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* This logical eraseblock is already locked. The newly |
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* allocated lock entry is not needed. |
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*/ |
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le_free = le; |
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le = le1; |
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} else { |
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struct rb_node **p, *parent = NULL; |
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|
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/* |
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* No lock entry, add the newly allocated one to the |
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* @ubi->ltree RB-tree. |
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*/ |
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le_free = NULL; |
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|
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p = &ubi->ltree.rb_node; |
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while (*p) { |
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parent = *p; |
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le1 = rb_entry(parent, struct ubi_ltree_entry, rb); |
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|
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if (vol_id < le1->vol_id) |
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p = &(*p)->rb_left; |
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else if (vol_id > le1->vol_id) |
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p = &(*p)->rb_right; |
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else { |
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ubi_assert(lnum != le1->lnum); |
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if (lnum < le1->lnum) |
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p = &(*p)->rb_left; |
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else |
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p = &(*p)->rb_right; |
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} |
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} |
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|
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rb_link_node(&le->rb, parent, p); |
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rb_insert_color(&le->rb, &ubi->ltree); |
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} |
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le->users += 1; |
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spin_unlock(&ubi->ltree_lock); |
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|
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kfree(le_free); |
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return le; |
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} |
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|
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/** |
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* leb_read_lock - lock logical eraseblock for reading. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* @lnum: logical eraseblock number |
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* |
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* This function locks a logical eraseblock for reading. Returns zero in case |
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* of success and a negative error code in case of failure. |
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*/ |
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static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum) |
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{ |
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struct ubi_ltree_entry *le; |
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|
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le = ltree_add_entry(ubi, vol_id, lnum); |
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if (IS_ERR(le)) |
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return PTR_ERR(le); |
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down_read(&le->mutex); |
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return 0; |
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} |
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|
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/** |
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* leb_read_unlock - unlock logical eraseblock. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* @lnum: logical eraseblock number |
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*/ |
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static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum) |
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{ |
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struct ubi_ltree_entry *le; |
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|
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spin_lock(&ubi->ltree_lock); |
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le = ltree_lookup(ubi, vol_id, lnum); |
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le->users -= 1; |
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ubi_assert(le->users >= 0); |
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up_read(&le->mutex); |
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if (le->users == 0) { |
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rb_erase(&le->rb, &ubi->ltree); |
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kfree(le); |
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} |
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spin_unlock(&ubi->ltree_lock); |
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} |
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|
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/** |
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* leb_write_lock - lock logical eraseblock for writing. |
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* @ubi: UBI device description object |
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* @vol_id: volume ID |
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* @lnum: logical eraseblock number |
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* |
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* This function locks a logical eraseblock for writing. Returns zero in case |
|
* of success and a negative error code in case of failure. |
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*/ |
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static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum) |
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{ |
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struct ubi_ltree_entry *le; |
|
|
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le = ltree_add_entry(ubi, vol_id, lnum); |
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if (IS_ERR(le)) |
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return PTR_ERR(le); |
|
down_write(&le->mutex); |
|
return 0; |
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} |
|
|
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/** |
|
* leb_write_trylock - try to lock logical eraseblock for writing. |
|
* @ubi: UBI device description object |
|
* @vol_id: volume ID |
|
* @lnum: logical eraseblock number |
|
* |
|
* This function locks a logical eraseblock for writing if there is no |
|
* contention and does nothing if there is contention. Returns %0 in case of |
|
* success, %1 in case of contention, and and a negative error code in case of |
|
* failure. |
|
*/ |
|
static int leb_write_trylock(struct ubi_device *ubi, int vol_id, int lnum) |
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{ |
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struct ubi_ltree_entry *le; |
|
|
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le = ltree_add_entry(ubi, vol_id, lnum); |
|
if (IS_ERR(le)) |
|
return PTR_ERR(le); |
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if (down_write_trylock(&le->mutex)) |
|
return 0; |
|
|
|
/* Contention, cancel */ |
|
spin_lock(&ubi->ltree_lock); |
|
le->users -= 1; |
|
ubi_assert(le->users >= 0); |
|
if (le->users == 0) { |
|
rb_erase(&le->rb, &ubi->ltree); |
|
kfree(le); |
|
} |
|
spin_unlock(&ubi->ltree_lock); |
|
|
|
return 1; |
|
} |
|
|
|
/** |
|
* leb_write_unlock - unlock logical eraseblock. |
|
* @ubi: UBI device description object |
|
* @vol_id: volume ID |
|
* @lnum: logical eraseblock number |
|
*/ |
|
static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum) |
|
{ |
|
struct ubi_ltree_entry *le; |
|
|
|
spin_lock(&ubi->ltree_lock); |
|
le = ltree_lookup(ubi, vol_id, lnum); |
|
le->users -= 1; |
|
ubi_assert(le->users >= 0); |
|
up_write(&le->mutex); |
|
if (le->users == 0) { |
|
rb_erase(&le->rb, &ubi->ltree); |
|
kfree(le); |
|
} |
|
spin_unlock(&ubi->ltree_lock); |
|
} |
|
|
|
/** |
|
* ubi_eba_is_mapped - check if a LEB is mapped. |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* |
|
* This function returns true if the LEB is mapped, false otherwise. |
|
*/ |
|
bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum) |
|
{ |
|
return vol->eba_tbl->entries[lnum].pnum >= 0; |
|
} |
|
|
|
/** |
|
* ubi_eba_unmap_leb - un-map logical eraseblock. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* |
|
* This function un-maps logical eraseblock @lnum and schedules corresponding |
|
* physical eraseblock for erasure. Returns zero in case of success and a |
|
* negative error code in case of failure. |
|
*/ |
|
int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol, |
|
int lnum) |
|
{ |
|
int err, pnum, vol_id = vol->vol_id; |
|
|
|
if (ubi->ro_mode) |
|
return -EROFS; |
|
|
|
err = leb_write_lock(ubi, vol_id, lnum); |
|
if (err) |
|
return err; |
|
|
|
pnum = vol->eba_tbl->entries[lnum].pnum; |
|
if (pnum < 0) |
|
/* This logical eraseblock is already unmapped */ |
|
goto out_unlock; |
|
|
|
dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum); |
|
|
|
down_read(&ubi->fm_eba_sem); |
|
vol->eba_tbl->entries[lnum].pnum = UBI_LEB_UNMAPPED; |
|
up_read(&ubi->fm_eba_sem); |
|
err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 0); |
|
|
|
out_unlock: |
|
leb_write_unlock(ubi, vol_id, lnum); |
|
return err; |
|
} |
|
|
|
#ifdef CONFIG_MTD_UBI_FASTMAP |
|
/** |
|
* check_mapping - check and fixup a mapping |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @pnum: physical eraseblock number |
|
* |
|
* Checks whether a given mapping is valid. Fastmap cannot track LEB unmap |
|
* operations, if such an operation is interrupted the mapping still looks |
|
* good, but upon first read an ECC is reported to the upper layer. |
|
* Normaly during the full-scan at attach time this is fixed, for Fastmap |
|
* we have to deal with it while reading. |
|
* If the PEB behind a LEB shows this symthom we change the mapping to |
|
* %UBI_LEB_UNMAPPED and schedule the PEB for erasure. |
|
* |
|
* Returns 0 on success, negative error code in case of failure. |
|
*/ |
|
static int check_mapping(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, |
|
int *pnum) |
|
{ |
|
int err; |
|
struct ubi_vid_io_buf *vidb; |
|
struct ubi_vid_hdr *vid_hdr; |
|
|
|
if (!ubi->fast_attach) |
|
return 0; |
|
|
|
if (!vol->checkmap || test_bit(lnum, vol->checkmap)) |
|
return 0; |
|
|
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) |
|
return -ENOMEM; |
|
|
|
err = ubi_io_read_vid_hdr(ubi, *pnum, vidb, 0); |
|
if (err > 0 && err != UBI_IO_BITFLIPS) { |
|
int torture = 0; |
|
|
|
switch (err) { |
|
case UBI_IO_FF: |
|
case UBI_IO_FF_BITFLIPS: |
|
case UBI_IO_BAD_HDR: |
|
case UBI_IO_BAD_HDR_EBADMSG: |
|
break; |
|
default: |
|
ubi_assert(0); |
|
} |
|
|
|
if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_FF_BITFLIPS) |
|
torture = 1; |
|
|
|
down_read(&ubi->fm_eba_sem); |
|
vol->eba_tbl->entries[lnum].pnum = UBI_LEB_UNMAPPED; |
|
up_read(&ubi->fm_eba_sem); |
|
ubi_wl_put_peb(ubi, vol->vol_id, lnum, *pnum, torture); |
|
|
|
*pnum = UBI_LEB_UNMAPPED; |
|
} else if (err < 0) { |
|
ubi_err(ubi, "unable to read VID header back from PEB %i: %i", |
|
*pnum, err); |
|
|
|
goto out_free; |
|
} else { |
|
int found_vol_id, found_lnum; |
|
|
|
ubi_assert(err == 0 || err == UBI_IO_BITFLIPS); |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
found_vol_id = be32_to_cpu(vid_hdr->vol_id); |
|
found_lnum = be32_to_cpu(vid_hdr->lnum); |
|
|
|
if (found_lnum != lnum || found_vol_id != vol->vol_id) { |
|
ubi_err(ubi, "EBA mismatch! PEB %i is LEB %i:%i instead of LEB %i:%i", |
|
*pnum, found_vol_id, found_lnum, vol->vol_id, lnum); |
|
ubi_ro_mode(ubi); |
|
err = -EINVAL; |
|
goto out_free; |
|
} |
|
} |
|
|
|
set_bit(lnum, vol->checkmap); |
|
err = 0; |
|
|
|
out_free: |
|
ubi_free_vid_buf(vidb); |
|
|
|
return err; |
|
} |
|
#else |
|
static int check_mapping(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, |
|
int *pnum) |
|
{ |
|
return 0; |
|
} |
|
#endif |
|
|
|
/** |
|
* ubi_eba_read_leb - read data. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @buf: buffer to store the read data |
|
* @offset: offset from where to read |
|
* @len: how many bytes to read |
|
* @check: data CRC check flag |
|
* |
|
* If the logical eraseblock @lnum is unmapped, @buf is filled with 0xFF |
|
* bytes. The @check flag only makes sense for static volumes and forces |
|
* eraseblock data CRC checking. |
|
* |
|
* In case of success this function returns zero. In case of a static volume, |
|
* if data CRC mismatches - %-EBADMSG is returned. %-EBADMSG may also be |
|
* returned for any volume type if an ECC error was detected by the MTD device |
|
* driver. Other negative error cored may be returned in case of other errors. |
|
*/ |
|
int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, |
|
void *buf, int offset, int len, int check) |
|
{ |
|
int err, pnum, scrub = 0, vol_id = vol->vol_id; |
|
struct ubi_vid_io_buf *vidb; |
|
struct ubi_vid_hdr *vid_hdr; |
|
uint32_t crc; |
|
|
|
err = leb_read_lock(ubi, vol_id, lnum); |
|
if (err) |
|
return err; |
|
|
|
pnum = vol->eba_tbl->entries[lnum].pnum; |
|
if (pnum >= 0) { |
|
err = check_mapping(ubi, vol, lnum, &pnum); |
|
if (err < 0) |
|
goto out_unlock; |
|
} |
|
|
|
if (pnum == UBI_LEB_UNMAPPED) { |
|
/* |
|
* The logical eraseblock is not mapped, fill the whole buffer |
|
* with 0xFF bytes. The exception is static volumes for which |
|
* it is an error to read unmapped logical eraseblocks. |
|
*/ |
|
dbg_eba("read %d bytes from offset %d of LEB %d:%d (unmapped)", |
|
len, offset, vol_id, lnum); |
|
leb_read_unlock(ubi, vol_id, lnum); |
|
ubi_assert(vol->vol_type != UBI_STATIC_VOLUME); |
|
memset(buf, 0xFF, len); |
|
return 0; |
|
} |
|
|
|
dbg_eba("read %d bytes from offset %d of LEB %d:%d, PEB %d", |
|
len, offset, vol_id, lnum, pnum); |
|
|
|
if (vol->vol_type == UBI_DYNAMIC_VOLUME) |
|
check = 0; |
|
|
|
retry: |
|
if (check) { |
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) { |
|
err = -ENOMEM; |
|
goto out_unlock; |
|
} |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
|
|
err = ubi_io_read_vid_hdr(ubi, pnum, vidb, 1); |
|
if (err && err != UBI_IO_BITFLIPS) { |
|
if (err > 0) { |
|
/* |
|
* The header is either absent or corrupted. |
|
* The former case means there is a bug - |
|
* switch to read-only mode just in case. |
|
* The latter case means a real corruption - we |
|
* may try to recover data. FIXME: but this is |
|
* not implemented. |
|
*/ |
|
if (err == UBI_IO_BAD_HDR_EBADMSG || |
|
err == UBI_IO_BAD_HDR) { |
|
ubi_warn(ubi, "corrupted VID header at PEB %d, LEB %d:%d", |
|
pnum, vol_id, lnum); |
|
err = -EBADMSG; |
|
} else { |
|
/* |
|
* Ending up here in the non-Fastmap case |
|
* is a clear bug as the VID header had to |
|
* be present at scan time to have it referenced. |
|
* With fastmap the story is more complicated. |
|
* Fastmap has the mapping info without the need |
|
* of a full scan. So the LEB could have been |
|
* unmapped, Fastmap cannot know this and keeps |
|
* the LEB referenced. |
|
* This is valid and works as the layer above UBI |
|
* has to do bookkeeping about used/referenced |
|
* LEBs in any case. |
|
*/ |
|
if (ubi->fast_attach) { |
|
err = -EBADMSG; |
|
} else { |
|
err = -EINVAL; |
|
ubi_ro_mode(ubi); |
|
} |
|
} |
|
} |
|
goto out_free; |
|
} else if (err == UBI_IO_BITFLIPS) |
|
scrub = 1; |
|
|
|
ubi_assert(lnum < be32_to_cpu(vid_hdr->used_ebs)); |
|
ubi_assert(len == be32_to_cpu(vid_hdr->data_size)); |
|
|
|
crc = be32_to_cpu(vid_hdr->data_crc); |
|
ubi_free_vid_buf(vidb); |
|
} |
|
|
|
err = ubi_io_read_data(ubi, buf, pnum, offset, len); |
|
if (err) { |
|
if (err == UBI_IO_BITFLIPS) |
|
scrub = 1; |
|
else if (mtd_is_eccerr(err)) { |
|
if (vol->vol_type == UBI_DYNAMIC_VOLUME) |
|
goto out_unlock; |
|
scrub = 1; |
|
if (!check) { |
|
ubi_msg(ubi, "force data checking"); |
|
check = 1; |
|
goto retry; |
|
} |
|
} else |
|
goto out_unlock; |
|
} |
|
|
|
if (check) { |
|
uint32_t crc1 = crc32(UBI_CRC32_INIT, buf, len); |
|
if (crc1 != crc) { |
|
ubi_warn(ubi, "CRC error: calculated %#08x, must be %#08x", |
|
crc1, crc); |
|
err = -EBADMSG; |
|
goto out_unlock; |
|
} |
|
} |
|
|
|
if (scrub) |
|
err = ubi_wl_scrub_peb(ubi, pnum); |
|
|
|
leb_read_unlock(ubi, vol_id, lnum); |
|
return err; |
|
|
|
out_free: |
|
ubi_free_vid_buf(vidb); |
|
out_unlock: |
|
leb_read_unlock(ubi, vol_id, lnum); |
|
return err; |
|
} |
|
|
|
/** |
|
* ubi_eba_read_leb_sg - read data into a scatter gather list. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @sgl: UBI scatter gather list to store the read data |
|
* @offset: offset from where to read |
|
* @len: how many bytes to read |
|
* @check: data CRC check flag |
|
* |
|
* This function works exactly like ubi_eba_read_leb(). But instead of |
|
* storing the read data into a buffer it writes to an UBI scatter gather |
|
* list. |
|
*/ |
|
int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol, |
|
struct ubi_sgl *sgl, int lnum, int offset, int len, |
|
int check) |
|
{ |
|
int to_read; |
|
int ret; |
|
struct scatterlist *sg; |
|
|
|
for (;;) { |
|
ubi_assert(sgl->list_pos < UBI_MAX_SG_COUNT); |
|
sg = &sgl->sg[sgl->list_pos]; |
|
if (len < sg->length - sgl->page_pos) |
|
to_read = len; |
|
else |
|
to_read = sg->length - sgl->page_pos; |
|
|
|
ret = ubi_eba_read_leb(ubi, vol, lnum, |
|
sg_virt(sg) + sgl->page_pos, offset, |
|
to_read, check); |
|
if (ret < 0) |
|
return ret; |
|
|
|
offset += to_read; |
|
len -= to_read; |
|
if (!len) { |
|
sgl->page_pos += to_read; |
|
if (sgl->page_pos == sg->length) { |
|
sgl->list_pos++; |
|
sgl->page_pos = 0; |
|
} |
|
|
|
break; |
|
} |
|
|
|
sgl->list_pos++; |
|
sgl->page_pos = 0; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/** |
|
* try_recover_peb - try to recover from write failure. |
|
* @vol: volume description object |
|
* @pnum: the physical eraseblock to recover |
|
* @lnum: logical eraseblock number |
|
* @buf: data which was not written because of the write failure |
|
* @offset: offset of the failed write |
|
* @len: how many bytes should have been written |
|
* @vidb: VID buffer |
|
* @retry: whether the caller should retry in case of failure |
|
* |
|
* This function is called in case of a write failure and moves all good data |
|
* from the potentially bad physical eraseblock to a good physical eraseblock. |
|
* This function also writes the data which was not written due to the failure. |
|
* Returns 0 in case of success, and a negative error code in case of failure. |
|
* In case of failure, the %retry parameter is set to false if this is a fatal |
|
* error (retrying won't help), and true otherwise. |
|
*/ |
|
static int try_recover_peb(struct ubi_volume *vol, int pnum, int lnum, |
|
const void *buf, int offset, int len, |
|
struct ubi_vid_io_buf *vidb, bool *retry) |
|
{ |
|
struct ubi_device *ubi = vol->ubi; |
|
struct ubi_vid_hdr *vid_hdr; |
|
int new_pnum, err, vol_id = vol->vol_id, data_size; |
|
uint32_t crc; |
|
|
|
*retry = false; |
|
|
|
new_pnum = ubi_wl_get_peb(ubi); |
|
if (new_pnum < 0) { |
|
err = new_pnum; |
|
goto out_put; |
|
} |
|
|
|
ubi_msg(ubi, "recover PEB %d, move data to PEB %d", |
|
pnum, new_pnum); |
|
|
|
err = ubi_io_read_vid_hdr(ubi, pnum, vidb, 1); |
|
if (err && err != UBI_IO_BITFLIPS) { |
|
if (err > 0) |
|
err = -EIO; |
|
goto out_put; |
|
} |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
ubi_assert(vid_hdr->vol_type == UBI_VID_DYNAMIC); |
|
|
|
mutex_lock(&ubi->buf_mutex); |
|
memset(ubi->peb_buf + offset, 0xFF, len); |
|
|
|
/* Read everything before the area where the write failure happened */ |
|
if (offset > 0) { |
|
err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, offset); |
|
if (err && err != UBI_IO_BITFLIPS) |
|
goto out_unlock; |
|
} |
|
|
|
*retry = true; |
|
|
|
memcpy(ubi->peb_buf + offset, buf, len); |
|
|
|
data_size = offset + len; |
|
crc = crc32(UBI_CRC32_INIT, ubi->peb_buf, data_size); |
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
vid_hdr->copy_flag = 1; |
|
vid_hdr->data_size = cpu_to_be32(data_size); |
|
vid_hdr->data_crc = cpu_to_be32(crc); |
|
err = ubi_io_write_vid_hdr(ubi, new_pnum, vidb); |
|
if (err) |
|
goto out_unlock; |
|
|
|
err = ubi_io_write_data(ubi, ubi->peb_buf, new_pnum, 0, data_size); |
|
|
|
out_unlock: |
|
mutex_unlock(&ubi->buf_mutex); |
|
|
|
if (!err) |
|
vol->eba_tbl->entries[lnum].pnum = new_pnum; |
|
|
|
out_put: |
|
up_read(&ubi->fm_eba_sem); |
|
|
|
if (!err) { |
|
ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); |
|
ubi_msg(ubi, "data was successfully recovered"); |
|
} else if (new_pnum >= 0) { |
|
/* |
|
* Bad luck? This physical eraseblock is bad too? Crud. Let's |
|
* try to get another one. |
|
*/ |
|
ubi_wl_put_peb(ubi, vol_id, lnum, new_pnum, 1); |
|
ubi_warn(ubi, "failed to write to PEB %d", new_pnum); |
|
} |
|
|
|
return err; |
|
} |
|
|
|
/** |
|
* recover_peb - recover from write failure. |
|
* @ubi: UBI device description object |
|
* @pnum: the physical eraseblock to recover |
|
* @vol_id: volume ID |
|
* @lnum: logical eraseblock number |
|
* @buf: data which was not written because of the write failure |
|
* @offset: offset of the failed write |
|
* @len: how many bytes should have been written |
|
* |
|
* This function is called in case of a write failure and moves all good data |
|
* from the potentially bad physical eraseblock to a good physical eraseblock. |
|
* This function also writes the data which was not written due to the failure. |
|
* Returns 0 in case of success, and a negative error code in case of failure. |
|
* This function tries %UBI_IO_RETRIES before giving up. |
|
*/ |
|
static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum, |
|
const void *buf, int offset, int len) |
|
{ |
|
int err, idx = vol_id2idx(ubi, vol_id), tries; |
|
struct ubi_volume *vol = ubi->volumes[idx]; |
|
struct ubi_vid_io_buf *vidb; |
|
|
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) |
|
return -ENOMEM; |
|
|
|
for (tries = 0; tries <= UBI_IO_RETRIES; tries++) { |
|
bool retry; |
|
|
|
err = try_recover_peb(vol, pnum, lnum, buf, offset, len, vidb, |
|
&retry); |
|
if (!err || !retry) |
|
break; |
|
|
|
ubi_msg(ubi, "try again"); |
|
} |
|
|
|
ubi_free_vid_buf(vidb); |
|
|
|
return err; |
|
} |
|
|
|
/** |
|
* try_write_vid_and_data - try to write VID header and data to a new PEB. |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @vidb: the VID buffer to write |
|
* @buf: buffer containing the data |
|
* @offset: where to start writing data |
|
* @len: how many bytes should be written |
|
* |
|
* This function tries to write VID header and data belonging to logical |
|
* eraseblock @lnum of volume @vol to a new physical eraseblock. Returns zero |
|
* in case of success and a negative error code in case of failure. |
|
* In case of error, it is possible that something was still written to the |
|
* flash media, but may be some garbage. |
|
*/ |
|
static int try_write_vid_and_data(struct ubi_volume *vol, int lnum, |
|
struct ubi_vid_io_buf *vidb, const void *buf, |
|
int offset, int len) |
|
{ |
|
struct ubi_device *ubi = vol->ubi; |
|
int pnum, opnum, err, vol_id = vol->vol_id; |
|
|
|
pnum = ubi_wl_get_peb(ubi); |
|
if (pnum < 0) { |
|
err = pnum; |
|
goto out_put; |
|
} |
|
|
|
opnum = vol->eba_tbl->entries[lnum].pnum; |
|
|
|
dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d", |
|
len, offset, vol_id, lnum, pnum); |
|
|
|
err = ubi_io_write_vid_hdr(ubi, pnum, vidb); |
|
if (err) { |
|
ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d", |
|
vol_id, lnum, pnum); |
|
goto out_put; |
|
} |
|
|
|
if (len) { |
|
err = ubi_io_write_data(ubi, buf, pnum, offset, len); |
|
if (err) { |
|
ubi_warn(ubi, |
|
"failed to write %d bytes at offset %d of LEB %d:%d, PEB %d", |
|
len, offset, vol_id, lnum, pnum); |
|
goto out_put; |
|
} |
|
} |
|
|
|
vol->eba_tbl->entries[lnum].pnum = pnum; |
|
|
|
out_put: |
|
up_read(&ubi->fm_eba_sem); |
|
|
|
if (err && pnum >= 0) |
|
err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); |
|
else if (!err && opnum >= 0) |
|
err = ubi_wl_put_peb(ubi, vol_id, lnum, opnum, 0); |
|
|
|
return err; |
|
} |
|
|
|
/** |
|
* ubi_eba_write_leb - write data to dynamic volume. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @buf: the data to write |
|
* @offset: offset within the logical eraseblock where to write |
|
* @len: how many bytes to write |
|
* |
|
* This function writes data to logical eraseblock @lnum of a dynamic volume |
|
* @vol. Returns zero in case of success and a negative error code in case |
|
* of failure. In case of error, it is possible that something was still |
|
* written to the flash media, but may be some garbage. |
|
* This function retries %UBI_IO_RETRIES times before giving up. |
|
*/ |
|
int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, |
|
const void *buf, int offset, int len) |
|
{ |
|
int err, pnum, tries, vol_id = vol->vol_id; |
|
struct ubi_vid_io_buf *vidb; |
|
struct ubi_vid_hdr *vid_hdr; |
|
|
|
if (ubi->ro_mode) |
|
return -EROFS; |
|
|
|
err = leb_write_lock(ubi, vol_id, lnum); |
|
if (err) |
|
return err; |
|
|
|
pnum = vol->eba_tbl->entries[lnum].pnum; |
|
if (pnum >= 0) { |
|
err = check_mapping(ubi, vol, lnum, &pnum); |
|
if (err < 0) |
|
goto out; |
|
} |
|
|
|
if (pnum >= 0) { |
|
dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d", |
|
len, offset, vol_id, lnum, pnum); |
|
|
|
err = ubi_io_write_data(ubi, buf, pnum, offset, len); |
|
if (err) { |
|
ubi_warn(ubi, "failed to write data to PEB %d", pnum); |
|
if (err == -EIO && ubi->bad_allowed) |
|
err = recover_peb(ubi, pnum, vol_id, lnum, buf, |
|
offset, len); |
|
} |
|
|
|
goto out; |
|
} |
|
|
|
/* |
|
* The logical eraseblock is not mapped. We have to get a free physical |
|
* eraseblock and write the volume identifier header there first. |
|
*/ |
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) { |
|
leb_write_unlock(ubi, vol_id, lnum); |
|
return -ENOMEM; |
|
} |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
|
|
vid_hdr->vol_type = UBI_VID_DYNAMIC; |
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
vid_hdr->vol_id = cpu_to_be32(vol_id); |
|
vid_hdr->lnum = cpu_to_be32(lnum); |
|
vid_hdr->compat = ubi_get_compat(ubi, vol_id); |
|
vid_hdr->data_pad = cpu_to_be32(vol->data_pad); |
|
|
|
for (tries = 0; tries <= UBI_IO_RETRIES; tries++) { |
|
err = try_write_vid_and_data(vol, lnum, vidb, buf, offset, len); |
|
if (err != -EIO || !ubi->bad_allowed) |
|
break; |
|
|
|
/* |
|
* Fortunately, this is the first write operation to this |
|
* physical eraseblock, so just put it and request a new one. |
|
* We assume that if this physical eraseblock went bad, the |
|
* erase code will handle that. |
|
*/ |
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
ubi_msg(ubi, "try another PEB"); |
|
} |
|
|
|
ubi_free_vid_buf(vidb); |
|
|
|
out: |
|
if (err) |
|
ubi_ro_mode(ubi); |
|
|
|
leb_write_unlock(ubi, vol_id, lnum); |
|
|
|
return err; |
|
} |
|
|
|
/** |
|
* ubi_eba_write_leb_st - write data to static volume. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @buf: data to write |
|
* @len: how many bytes to write |
|
* @used_ebs: how many logical eraseblocks will this volume contain |
|
* |
|
* This function writes data to logical eraseblock @lnum of static volume |
|
* @vol. The @used_ebs argument should contain total number of logical |
|
* eraseblock in this static volume. |
|
* |
|
* When writing to the last logical eraseblock, the @len argument doesn't have |
|
* to be aligned to the minimal I/O unit size. Instead, it has to be equivalent |
|
* to the real data size, although the @buf buffer has to contain the |
|
* alignment. In all other cases, @len has to be aligned. |
|
* |
|
* It is prohibited to write more than once to logical eraseblocks of static |
|
* volumes. This function returns zero in case of success and a negative error |
|
* code in case of failure. |
|
*/ |
|
int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, |
|
int lnum, const void *buf, int len, int used_ebs) |
|
{ |
|
int err, tries, data_size = len, vol_id = vol->vol_id; |
|
struct ubi_vid_io_buf *vidb; |
|
struct ubi_vid_hdr *vid_hdr; |
|
uint32_t crc; |
|
|
|
if (ubi->ro_mode) |
|
return -EROFS; |
|
|
|
if (lnum == used_ebs - 1) |
|
/* If this is the last LEB @len may be unaligned */ |
|
len = ALIGN(data_size, ubi->min_io_size); |
|
else |
|
ubi_assert(!(len & (ubi->min_io_size - 1))); |
|
|
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) |
|
return -ENOMEM; |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
|
|
err = leb_write_lock(ubi, vol_id, lnum); |
|
if (err) |
|
goto out; |
|
|
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
vid_hdr->vol_id = cpu_to_be32(vol_id); |
|
vid_hdr->lnum = cpu_to_be32(lnum); |
|
vid_hdr->compat = ubi_get_compat(ubi, vol_id); |
|
vid_hdr->data_pad = cpu_to_be32(vol->data_pad); |
|
|
|
crc = crc32(UBI_CRC32_INIT, buf, data_size); |
|
vid_hdr->vol_type = UBI_VID_STATIC; |
|
vid_hdr->data_size = cpu_to_be32(data_size); |
|
vid_hdr->used_ebs = cpu_to_be32(used_ebs); |
|
vid_hdr->data_crc = cpu_to_be32(crc); |
|
|
|
ubi_assert(vol->eba_tbl->entries[lnum].pnum < 0); |
|
|
|
for (tries = 0; tries <= UBI_IO_RETRIES; tries++) { |
|
err = try_write_vid_and_data(vol, lnum, vidb, buf, 0, len); |
|
if (err != -EIO || !ubi->bad_allowed) |
|
break; |
|
|
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
ubi_msg(ubi, "try another PEB"); |
|
} |
|
|
|
if (err) |
|
ubi_ro_mode(ubi); |
|
|
|
leb_write_unlock(ubi, vol_id, lnum); |
|
|
|
out: |
|
ubi_free_vid_buf(vidb); |
|
|
|
return err; |
|
} |
|
|
|
/* |
|
* ubi_eba_atomic_leb_change - change logical eraseblock atomically. |
|
* @ubi: UBI device description object |
|
* @vol: volume description object |
|
* @lnum: logical eraseblock number |
|
* @buf: data to write |
|
* @len: how many bytes to write |
|
* |
|
* This function changes the contents of a logical eraseblock atomically. @buf |
|
* has to contain new logical eraseblock data, and @len - the length of the |
|
* data, which has to be aligned. This function guarantees that in case of an |
|
* unclean reboot the old contents is preserved. Returns zero in case of |
|
* success and a negative error code in case of failure. |
|
* |
|
* UBI reserves one LEB for the "atomic LEB change" operation, so only one |
|
* LEB change may be done at a time. This is ensured by @ubi->alc_mutex. |
|
*/ |
|
int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol, |
|
int lnum, const void *buf, int len) |
|
{ |
|
int err, tries, vol_id = vol->vol_id; |
|
struct ubi_vid_io_buf *vidb; |
|
struct ubi_vid_hdr *vid_hdr; |
|
uint32_t crc; |
|
|
|
if (ubi->ro_mode) |
|
return -EROFS; |
|
|
|
if (len == 0) { |
|
/* |
|
* Special case when data length is zero. In this case the LEB |
|
* has to be unmapped and mapped somewhere else. |
|
*/ |
|
err = ubi_eba_unmap_leb(ubi, vol, lnum); |
|
if (err) |
|
return err; |
|
return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0); |
|
} |
|
|
|
vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
|
if (!vidb) |
|
return -ENOMEM; |
|
|
|
vid_hdr = ubi_get_vid_hdr(vidb); |
|
|
|
mutex_lock(&ubi->alc_mutex); |
|
err = leb_write_lock(ubi, vol_id, lnum); |
|
if (err) |
|
goto out_mutex; |
|
|
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
vid_hdr->vol_id = cpu_to_be32(vol_id); |
|
vid_hdr->lnum = cpu_to_be32(lnum); |
|
vid_hdr->compat = ubi_get_compat(ubi, vol_id); |
|
vid_hdr->data_pad = cpu_to_be32(vol->data_pad); |
|
|
|
crc = crc32(UBI_CRC32_INIT, buf, len); |
|
vid_hdr->vol_type = UBI_VID_DYNAMIC; |
|
vid_hdr->data_size = cpu_to_be32(len); |
|
vid_hdr->copy_flag = 1; |
|
vid_hdr->data_crc = cpu_to_be32(crc); |
|
|
|
dbg_eba("change LEB %d:%d", vol_id, lnum); |
|
|
|
for (tries = 0; tries <= UBI_IO_RETRIES; tries++) { |
|
err = try_write_vid_and_data(vol, lnum, vidb, buf, 0, len); |
|
if (err != -EIO || !ubi->bad_allowed) |
|
break; |
|
|
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
ubi_msg(ubi, "try another PEB"); |
|
} |
|
|
|
/* |
|
* This flash device does not admit of bad eraseblocks or |
|
* something nasty and unexpected happened. Switch to read-only |
|
* mode just in case. |
|
*/ |
|
if (err) |
|
ubi_ro_mode(ubi); |
|
|
|
leb_write_unlock(ubi, vol_id, lnum); |
|
|
|
out_mutex: |
|
mutex_unlock(&ubi->alc_mutex); |
|
ubi_free_vid_buf(vidb); |
|
return err; |
|
} |
|
|
|
/** |
|
* is_error_sane - check whether a read error is sane. |
|
* @err: code of the error happened during reading |
|
* |
|
* This is a helper function for 'ubi_eba_copy_leb()' which is called when we |
|
* cannot read data from the target PEB (an error @err happened). If the error |
|
* code is sane, then we treat this error as non-fatal. Otherwise the error is |
|
* fatal and UBI will be switched to R/O mode later. |
|
* |
|
* The idea is that we try not to switch to R/O mode if the read error is |
|
* something which suggests there was a real read problem. E.g., %-EIO. Or a |
|
* memory allocation failed (-%ENOMEM). Otherwise, it is safer to switch to R/O |
|
* mode, simply because we do not know what happened at the MTD level, and we |
|
* cannot handle this. E.g., the underlying driver may have become crazy, and |
|
* it is safer to switch to R/O mode to preserve the data. |
|
* |
|
* And bear in mind, this is about reading from the target PEB, i.e. the PEB |
|
* which we have just written. |
|
*/ |
|
static int is_error_sane(int err) |
|
{ |
|
if (err == -EIO || err == -ENOMEM || err == UBI_IO_BAD_HDR || |
|
err == UBI_IO_BAD_HDR_EBADMSG || err == -ETIMEDOUT) |
|
return 0; |
|
return 1; |
|
} |
|
|
|
/** |
|
* ubi_eba_copy_leb - copy logical eraseblock. |
|
* @ubi: UBI device description object |
|
* @from: physical eraseblock number from where to copy |
|
* @to: physical eraseblock number where to copy |
|
* @vidb: data structure from where the VID header is derived |
|
* |
|
* This function copies logical eraseblock from physical eraseblock @from to |
|
* physical eraseblock @to. The @vid_hdr buffer may be changed by this |
|
* function. Returns: |
|
* o %0 in case of success; |
|
* o %MOVE_CANCEL_RACE, %MOVE_TARGET_WR_ERR, %MOVE_TARGET_BITFLIPS, etc; |
|
* o a negative error code in case of failure. |
|
*/ |
|
int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to, |
|
struct ubi_vid_io_buf *vidb) |
|
{ |
|
int err, vol_id, lnum, data_size, aldata_size, idx; |
|
struct ubi_vid_hdr *vid_hdr = ubi_get_vid_hdr(vidb); |
|
struct ubi_volume *vol; |
|
uint32_t crc; |
|
|
|
ubi_assert(rwsem_is_locked(&ubi->fm_eba_sem)); |
|
|
|
vol_id = be32_to_cpu(vid_hdr->vol_id); |
|
lnum = be32_to_cpu(vid_hdr->lnum); |
|
|
|
dbg_wl("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to); |
|
|
|
if (vid_hdr->vol_type == UBI_VID_STATIC) { |
|
data_size = be32_to_cpu(vid_hdr->data_size); |
|
aldata_size = ALIGN(data_size, ubi->min_io_size); |
|
} else |
|
data_size = aldata_size = |
|
ubi->leb_size - be32_to_cpu(vid_hdr->data_pad); |
|
|
|
idx = vol_id2idx(ubi, vol_id); |
|
spin_lock(&ubi->volumes_lock); |
|
/* |
|
* Note, we may race with volume deletion, which means that the volume |
|
* this logical eraseblock belongs to might be being deleted. Since the |
|
* volume deletion un-maps all the volume's logical eraseblocks, it will |
|
* be locked in 'ubi_wl_put_peb()' and wait for the WL worker to finish. |
|
*/ |
|
vol = ubi->volumes[idx]; |
|
spin_unlock(&ubi->volumes_lock); |
|
if (!vol) { |
|
/* No need to do further work, cancel */ |
|
dbg_wl("volume %d is being removed, cancel", vol_id); |
|
return MOVE_CANCEL_RACE; |
|
} |
|
|
|
/* |
|
* We do not want anybody to write to this logical eraseblock while we |
|
* are moving it, so lock it. |
|
* |
|
* Note, we are using non-waiting locking here, because we cannot sleep |
|
* on the LEB, since it may cause deadlocks. Indeed, imagine a task is |
|
* unmapping the LEB which is mapped to the PEB we are going to move |
|
* (@from). This task locks the LEB and goes sleep in the |
|
* 'ubi_wl_put_peb()' function on the @ubi->move_mutex. In turn, we are |
|
* holding @ubi->move_mutex and go sleep on the LEB lock. So, if the |
|
* LEB is already locked, we just do not move it and return |
|
* %MOVE_RETRY. Note, we do not return %MOVE_CANCEL_RACE here because |
|
* we do not know the reasons of the contention - it may be just a |
|
* normal I/O on this LEB, so we want to re-try. |
|
*/ |
|
err = leb_write_trylock(ubi, vol_id, lnum); |
|
if (err) { |
|
dbg_wl("contention on LEB %d:%d, cancel", vol_id, lnum); |
|
return MOVE_RETRY; |
|
} |
|
|
|
/* |
|
* The LEB might have been put meanwhile, and the task which put it is |
|
* probably waiting on @ubi->move_mutex. No need to continue the work, |
|
* cancel it. |
|
*/ |
|
if (vol->eba_tbl->entries[lnum].pnum != from) { |
|
dbg_wl("LEB %d:%d is no longer mapped to PEB %d, mapped to PEB %d, cancel", |
|
vol_id, lnum, from, vol->eba_tbl->entries[lnum].pnum); |
|
err = MOVE_CANCEL_RACE; |
|
goto out_unlock_leb; |
|
} |
|
|
|
/* |
|
* OK, now the LEB is locked and we can safely start moving it. Since |
|
* this function utilizes the @ubi->peb_buf buffer which is shared |
|
* with some other functions - we lock the buffer by taking the |
|
* @ubi->buf_mutex. |
|
*/ |
|
mutex_lock(&ubi->buf_mutex); |
|
dbg_wl("read %d bytes of data", aldata_size); |
|
err = ubi_io_read_data(ubi, ubi->peb_buf, from, 0, aldata_size); |
|
if (err && err != UBI_IO_BITFLIPS) { |
|
ubi_warn(ubi, "error %d while reading data from PEB %d", |
|
err, from); |
|
err = MOVE_SOURCE_RD_ERR; |
|
goto out_unlock_buf; |
|
} |
|
|
|
/* |
|
* Now we have got to calculate how much data we have to copy. In |
|
* case of a static volume it is fairly easy - the VID header contains |
|
* the data size. In case of a dynamic volume it is more difficult - we |
|
* have to read the contents, cut 0xFF bytes from the end and copy only |
|
* the first part. We must do this to avoid writing 0xFF bytes as it |
|
* may have some side-effects. And not only this. It is important not |
|
* to include those 0xFFs to CRC because later the they may be filled |
|
* by data. |
|
*/ |
|
if (vid_hdr->vol_type == UBI_VID_DYNAMIC) |
|
aldata_size = data_size = |
|
ubi_calc_data_len(ubi, ubi->peb_buf, data_size); |
|
|
|
cond_resched(); |
|
crc = crc32(UBI_CRC32_INIT, ubi->peb_buf, data_size); |
|
cond_resched(); |
|
|
|
/* |
|
* It may turn out to be that the whole @from physical eraseblock |
|
* contains only 0xFF bytes. Then we have to only write the VID header |
|
* and do not write any data. This also means we should not set |
|
* @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc. |
|
*/ |
|
if (data_size > 0) { |
|
vid_hdr->copy_flag = 1; |
|
vid_hdr->data_size = cpu_to_be32(data_size); |
|
vid_hdr->data_crc = cpu_to_be32(crc); |
|
} |
|
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); |
|
|
|
err = ubi_io_write_vid_hdr(ubi, to, vidb); |
|
if (err) { |
|
if (err == -EIO) |
|
err = MOVE_TARGET_WR_ERR; |
|
goto out_unlock_buf; |
|
} |
|
|
|
cond_resched(); |
|
|
|
/* Read the VID header back and check if it was written correctly */ |
|
err = ubi_io_read_vid_hdr(ubi, to, vidb, 1); |
|
if (err) { |
|
if (err != UBI_IO_BITFLIPS) { |
|
ubi_warn(ubi, "error %d while reading VID header back from PEB %d", |
|
err, to); |
|
if (is_error_sane(err)) |
|
err = MOVE_TARGET_RD_ERR; |
|
} else |
|
err = MOVE_TARGET_BITFLIPS; |
|
goto out_unlock_buf; |
|
} |
|
|
|
if (data_size > 0) { |
|
err = ubi_io_write_data(ubi, ubi->peb_buf, to, 0, aldata_size); |
|
if (err) { |
|
if (err == -EIO) |
|
err = MOVE_TARGET_WR_ERR; |
|
goto out_unlock_buf; |
|
} |
|
|
|
cond_resched(); |
|
} |
|
|
|
ubi_assert(vol->eba_tbl->entries[lnum].pnum == from); |
|
vol->eba_tbl->entries[lnum].pnum = to; |
|
|
|
out_unlock_buf: |
|
mutex_unlock(&ubi->buf_mutex); |
|
out_unlock_leb: |
|
leb_write_unlock(ubi, vol_id, lnum); |
|
return err; |
|
} |
|
|
|
/** |
|
* print_rsvd_warning - warn about not having enough reserved PEBs. |
|
* @ubi: UBI device description object |
|
* @ai: UBI attach info object |
|
* |
|
* This is a helper function for 'ubi_eba_init()' which is called when UBI |
|
* cannot reserve enough PEBs for bad block handling. This function makes a |
|
* decision whether we have to print a warning or not. The algorithm is as |
|
* follows: |
|
* o if this is a new UBI image, then just print the warning |
|
* o if this is an UBI image which has already been used for some time, print |
|
* a warning only if we can reserve less than 10% of the expected amount of |
|
* the reserved PEB. |
|
* |
|
* The idea is that when UBI is used, PEBs become bad, and the reserved pool |
|
* of PEBs becomes smaller, which is normal and we do not want to scare users |
|
* with a warning every time they attach the MTD device. This was an issue |
|
* reported by real users. |
|
*/ |
|
static void print_rsvd_warning(struct ubi_device *ubi, |
|
struct ubi_attach_info *ai) |
|
{ |
|
/* |
|
* The 1 << 18 (256KiB) number is picked randomly, just a reasonably |
|
* large number to distinguish between newly flashed and used images. |
|
*/ |
|
if (ai->max_sqnum > (1 << 18)) { |
|
int min = ubi->beb_rsvd_level / 10; |
|
|
|
if (!min) |
|
min = 1; |
|
if (ubi->beb_rsvd_pebs > min) |
|
return; |
|
} |
|
|
|
ubi_warn(ubi, "cannot reserve enough PEBs for bad PEB handling, reserved %d, need %d", |
|
ubi->beb_rsvd_pebs, ubi->beb_rsvd_level); |
|
if (ubi->corr_peb_count) |
|
ubi_warn(ubi, "%d PEBs are corrupted and not used", |
|
ubi->corr_peb_count); |
|
} |
|
|
|
/** |
|
* self_check_eba - run a self check on the EBA table constructed by fastmap. |
|
* @ubi: UBI device description object |
|
* @ai_fastmap: UBI attach info object created by fastmap |
|
* @ai_scan: UBI attach info object created by scanning |
|
* |
|
* Returns < 0 in case of an internal error, 0 otherwise. |
|
* If a bad EBA table entry was found it will be printed out and |
|
* ubi_assert() triggers. |
|
*/ |
|
int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap, |
|
struct ubi_attach_info *ai_scan) |
|
{ |
|
int i, j, num_volumes, ret = 0; |
|
int **scan_eba, **fm_eba; |
|
struct ubi_ainf_volume *av; |
|
struct ubi_volume *vol; |
|
struct ubi_ainf_peb *aeb; |
|
struct rb_node *rb; |
|
|
|
num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; |
|
|
|
scan_eba = kmalloc_array(num_volumes, sizeof(*scan_eba), GFP_KERNEL); |
|
if (!scan_eba) |
|
return -ENOMEM; |
|
|
|
fm_eba = kmalloc_array(num_volumes, sizeof(*fm_eba), GFP_KERNEL); |
|
if (!fm_eba) { |
|
kfree(scan_eba); |
|
return -ENOMEM; |
|
} |
|
|
|
for (i = 0; i < num_volumes; i++) { |
|
vol = ubi->volumes[i]; |
|
if (!vol) |
|
continue; |
|
|
|
scan_eba[i] = kmalloc_array(vol->reserved_pebs, |
|
sizeof(**scan_eba), |
|
GFP_KERNEL); |
|
if (!scan_eba[i]) { |
|
ret = -ENOMEM; |
|
goto out_free; |
|
} |
|
|
|
fm_eba[i] = kmalloc_array(vol->reserved_pebs, |
|
sizeof(**fm_eba), |
|
GFP_KERNEL); |
|
if (!fm_eba[i]) { |
|
ret = -ENOMEM; |
|
goto out_free; |
|
} |
|
|
|
for (j = 0; j < vol->reserved_pebs; j++) |
|
scan_eba[i][j] = fm_eba[i][j] = UBI_LEB_UNMAPPED; |
|
|
|
av = ubi_find_av(ai_scan, idx2vol_id(ubi, i)); |
|
if (!av) |
|
continue; |
|
|
|
ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) |
|
scan_eba[i][aeb->lnum] = aeb->pnum; |
|
|
|
av = ubi_find_av(ai_fastmap, idx2vol_id(ubi, i)); |
|
if (!av) |
|
continue; |
|
|
|
ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) |
|
fm_eba[i][aeb->lnum] = aeb->pnum; |
|
|
|
for (j = 0; j < vol->reserved_pebs; j++) { |
|
if (scan_eba[i][j] != fm_eba[i][j]) { |
|
if (scan_eba[i][j] == UBI_LEB_UNMAPPED || |
|
fm_eba[i][j] == UBI_LEB_UNMAPPED) |
|
continue; |
|
|
|
ubi_err(ubi, "LEB:%i:%i is PEB:%i instead of %i!", |
|
vol->vol_id, j, fm_eba[i][j], |
|
scan_eba[i][j]); |
|
ubi_assert(0); |
|
} |
|
} |
|
} |
|
|
|
out_free: |
|
for (i = 0; i < num_volumes; i++) { |
|
if (!ubi->volumes[i]) |
|
continue; |
|
|
|
kfree(scan_eba[i]); |
|
kfree(fm_eba[i]); |
|
} |
|
|
|
kfree(scan_eba); |
|
kfree(fm_eba); |
|
return ret; |
|
} |
|
|
|
/** |
|
* ubi_eba_init - initialize the EBA sub-system using attaching information. |
|
* @ubi: UBI device description object |
|
* @ai: attaching information |
|
* |
|
* This function returns zero in case of success and a negative error code in |
|
* case of failure. |
|
*/ |
|
int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai) |
|
{ |
|
int i, err, num_volumes; |
|
struct ubi_ainf_volume *av; |
|
struct ubi_volume *vol; |
|
struct ubi_ainf_peb *aeb; |
|
struct rb_node *rb; |
|
|
|
dbg_eba("initialize EBA sub-system"); |
|
|
|
spin_lock_init(&ubi->ltree_lock); |
|
mutex_init(&ubi->alc_mutex); |
|
ubi->ltree = RB_ROOT; |
|
|
|
ubi->global_sqnum = ai->max_sqnum + 1; |
|
num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; |
|
|
|
for (i = 0; i < num_volumes; i++) { |
|
struct ubi_eba_table *tbl; |
|
|
|
vol = ubi->volumes[i]; |
|
if (!vol) |
|
continue; |
|
|
|
cond_resched(); |
|
|
|
tbl = ubi_eba_create_table(vol, vol->reserved_pebs); |
|
if (IS_ERR(tbl)) { |
|
err = PTR_ERR(tbl); |
|
goto out_free; |
|
} |
|
|
|
ubi_eba_replace_table(vol, tbl); |
|
|
|
av = ubi_find_av(ai, idx2vol_id(ubi, i)); |
|
if (!av) |
|
continue; |
|
|
|
ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) { |
|
if (aeb->lnum >= vol->reserved_pebs) { |
|
/* |
|
* This may happen in case of an unclean reboot |
|
* during re-size. |
|
*/ |
|
ubi_move_aeb_to_list(av, aeb, &ai->erase); |
|
} else { |
|
struct ubi_eba_entry *entry; |
|
|
|
entry = &vol->eba_tbl->entries[aeb->lnum]; |
|
entry->pnum = aeb->pnum; |
|
} |
|
} |
|
} |
|
|
|
if (ubi->avail_pebs < EBA_RESERVED_PEBS) { |
|
ubi_err(ubi, "no enough physical eraseblocks (%d, need %d)", |
|
ubi->avail_pebs, EBA_RESERVED_PEBS); |
|
if (ubi->corr_peb_count) |
|
ubi_err(ubi, "%d PEBs are corrupted and not used", |
|
ubi->corr_peb_count); |
|
err = -ENOSPC; |
|
goto out_free; |
|
} |
|
ubi->avail_pebs -= EBA_RESERVED_PEBS; |
|
ubi->rsvd_pebs += EBA_RESERVED_PEBS; |
|
|
|
if (ubi->bad_allowed) { |
|
ubi_calculate_reserved(ubi); |
|
|
|
if (ubi->avail_pebs < ubi->beb_rsvd_level) { |
|
/* No enough free physical eraseblocks */ |
|
ubi->beb_rsvd_pebs = ubi->avail_pebs; |
|
print_rsvd_warning(ubi, ai); |
|
} else |
|
ubi->beb_rsvd_pebs = ubi->beb_rsvd_level; |
|
|
|
ubi->avail_pebs -= ubi->beb_rsvd_pebs; |
|
ubi->rsvd_pebs += ubi->beb_rsvd_pebs; |
|
} |
|
|
|
dbg_eba("EBA sub-system is initialized"); |
|
return 0; |
|
|
|
out_free: |
|
for (i = 0; i < num_volumes; i++) { |
|
if (!ubi->volumes[i]) |
|
continue; |
|
ubi_eba_replace_table(ubi->volumes[i], NULL); |
|
} |
|
return err; |
|
}
|
|
|