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authorDavid Woodhouse <David.Woodhouse@intel.com>2008-10-13 20:13:56 +0400
committerDavid Woodhouse <David.Woodhouse@intel.com>2008-10-13 20:13:56 +0400
commite758936e02700ff88a0b08b722a3847b95283ef2 (patch)
tree50c919bef1b459a778b85159d5929de95b6c4a01 /fs/ubifs
parent239cfbde1f5843c4a24199f117d5f67f637d72d5 (diff)
parent4480f15b3306f43bbb0310d461142b4e897ca45b (diff)
downloadlinux-e758936e02700ff88a0b08b722a3847b95283ef2.tar.xz
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: include/asm-x86/statfs.h
Diffstat (limited to 'fs/ubifs')
-rw-r--r--fs/ubifs/budget.c114
-rw-r--r--fs/ubifs/debug.c2
-rw-r--r--fs/ubifs/dir.c3
-rw-r--r--fs/ubifs/file.c20
-rw-r--r--fs/ubifs/find.c19
-rw-r--r--fs/ubifs/gc.c20
-rw-r--r--fs/ubifs/misc.h49
-rw-r--r--fs/ubifs/super.c25
-rw-r--r--fs/ubifs/tnc.c116
-rw-r--r--fs/ubifs/ubifs-media.h2
-rw-r--r--fs/ubifs/ubifs.h14
11 files changed, 235 insertions, 149 deletions
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
index 154098157473..73db464cd08b 100644
--- a/fs/ubifs/budget.c
+++ b/fs/ubifs/budget.c
@@ -302,18 +302,6 @@ long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs)
int subtract_lebs;
long long available;
- /*
- * Force the amount available to the total size reported if the used
- * space is zero.
- */
- if (c->lst.total_used <= UBIFS_INO_NODE_SZ &&
- c->budg_data_growth + c->budg_dd_growth == 0) {
- /* Do the same calculation as for c->block_cnt */
- available = c->main_lebs - 2;
- available *= c->leb_size - c->dark_wm;
- return available;
- }
-
available = c->main_bytes - c->lst.total_used;
/*
@@ -714,34 +702,106 @@ void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
}
/**
- * ubifs_budg_get_free_space - return amount of free space.
+ * ubifs_reported_space - calculate reported free space.
+ * @c: the UBIFS file-system description object
+ * @free: amount of free space
+ *
+ * This function calculates amount of free space which will be reported to
+ * user-space. User-space application tend to expect that if the file-system
+ * (e.g., via the 'statfs()' call) reports that it has N bytes available, they
+ * are able to write a file of size N. UBIFS attaches node headers to each data
+ * node and it has to write indexind nodes as well. This introduces additional
+ * overhead, and UBIFS it has to report sligtly less free space to meet the
+ * above expectetion.
+ *
+ * This function assumes free space is made up of uncompressed data nodes and
+ * full index nodes (one per data node, tripled because we always allow enough
+ * space to write the index thrice).
+ *
+ * Note, the calculation is pessimistic, which means that most of the time
+ * UBIFS reports less space than it actually has.
+ */
+long long ubifs_reported_space(const struct ubifs_info *c, uint64_t free)
+{
+ int divisor, factor, f;
+
+ /*
+ * Reported space size is @free * X, where X is UBIFS block size
+ * divided by UBIFS block size + all overhead one data block
+ * introduces. The overhead is the node header + indexing overhead.
+ *
+ * Indexing overhead calculations are based on the following formula:
+ * I = N/(f - 1) + 1, where I - number of indexing nodes, N - number
+ * of data nodes, f - fanout. Because effective UBIFS fanout is twice
+ * as less than maximum fanout, we assume that each data node
+ * introduces 3 * @c->max_idx_node_sz / (@c->fanout/2 - 1) bytes.
+ * Note, the multiplier 3 is because UBIFS reseves thrice as more space
+ * for the index.
+ */
+ f = c->fanout > 3 ? c->fanout >> 1 : 2;
+ factor = UBIFS_BLOCK_SIZE;
+ divisor = UBIFS_MAX_DATA_NODE_SZ;
+ divisor += (c->max_idx_node_sz * 3) / (f - 1);
+ free *= factor;
+ do_div(free, divisor);
+ return free;
+}
+
+/**
+ * ubifs_get_free_space - return amount of free space.
* @c: UBIFS file-system description object
*
- * This function returns amount of free space on the file-system.
+ * This function calculates amount of free space to report to user-space.
+ *
+ * Because UBIFS may introduce substantial overhead (the index, node headers,
+ * alighment, wastage at the end of eraseblocks, etc), it cannot report real
+ * amount of free flash space it has (well, because not all dirty space is
+ * reclamable, UBIFS does not actually know the real amount). If UBIFS did so,
+ * it would bread user expectetion about what free space is. Users seem to
+ * accustomed to assume that if the file-system reports N bytes of free space,
+ * they would be able to fit a file of N bytes to the FS. This almost works for
+ * traditional file-systems, because they have way less overhead than UBIFS.
+ * So, to keep users happy, UBIFS tries to take the overhead into account.
*/
-long long ubifs_budg_get_free_space(struct ubifs_info *c)
+long long ubifs_get_free_space(struct ubifs_info *c)
{
- int min_idx_lebs, rsvd_idx_lebs;
+ int min_idx_lebs, rsvd_idx_lebs, lebs;
long long available, outstanding, free;
- /* Do exactly the same calculations as in 'do_budget_space()' */
spin_lock(&c->space_lock);
min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+ outstanding = c->budg_data_growth + c->budg_dd_growth;
- if (min_idx_lebs > c->lst.idx_lebs)
- rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
- else
- rsvd_idx_lebs = 0;
-
- if (rsvd_idx_lebs > c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt
- - c->lst.taken_empty_lebs) {
+ /*
+ * Force the amount available to the total size reported if the used
+ * space is zero.
+ */
+ if (c->lst.total_used <= UBIFS_INO_NODE_SZ && !outstanding) {
spin_unlock(&c->space_lock);
- return 0;
+ return (long long)c->block_cnt << UBIFS_BLOCK_SHIFT;
}
available = ubifs_calc_available(c, min_idx_lebs);
- outstanding = c->budg_data_growth + c->budg_dd_growth;
- c->min_idx_lebs = min_idx_lebs;
+
+ /*
+ * When reporting free space to user-space, UBIFS guarantees that it is
+ * possible to write a file of free space size. This means that for
+ * empty LEBs we may use more precise calculations than
+ * 'ubifs_calc_available()' is using. Namely, we know that in empty
+ * LEBs we would waste only @c->leb_overhead bytes, not @c->dark_wm.
+ * Thus, amend the available space.
+ *
+ * Note, the calculations below are similar to what we have in
+ * 'do_budget_space()', so refer there for comments.
+ */
+ if (min_idx_lebs > c->lst.idx_lebs)
+ rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+ else
+ rsvd_idx_lebs = 0;
+ lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
+ c->lst.taken_empty_lebs;
+ lebs -= rsvd_idx_lebs;
+ available += lebs * (c->dark_wm - c->leb_overhead);
spin_unlock(&c->space_lock);
if (available > outstanding)
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index b9cb77473758..d7f7645779f2 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -538,7 +538,7 @@ void dbg_dump_node(const struct ubifs_info *c, const void *node)
printk(KERN_DEBUG "\t%d orphan inode numbers:\n", n);
for (i = 0; i < n; i++)
printk(KERN_DEBUG "\t ino %llu\n",
- le64_to_cpu(orph->inos[i]));
+ (unsigned long long)le64_to_cpu(orph->inos[i]));
break;
}
default:
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 5c96f1fb7016..526c01ec8003 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -426,7 +426,7 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
while (1) {
dbg_gen("feed '%s', ino %llu, new f_pos %#x",
- dent->name, le64_to_cpu(dent->inum),
+ dent->name, (unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(dent->ch.sqnum > ubifs_inode(dir)->creat_sqnum);
@@ -587,7 +587,6 @@ static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
if (err) {
if (err != -ENOSPC)
return err;
- err = 0;
budgeted = 0;
}
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 4071d1cae29f..3d698e2022b1 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -793,7 +793,7 @@ static int do_truncation(struct ubifs_info *c, struct inode *inode,
int err;
struct ubifs_budget_req req;
loff_t old_size = inode->i_size, new_size = attr->ia_size;
- int offset = new_size & (UBIFS_BLOCK_SIZE - 1);
+ int offset = new_size & (UBIFS_BLOCK_SIZE - 1), budgeted = 1;
struct ubifs_inode *ui = ubifs_inode(inode);
dbg_gen("ino %lu, size %lld -> %lld", inode->i_ino, old_size, new_size);
@@ -811,8 +811,15 @@ static int do_truncation(struct ubifs_info *c, struct inode *inode,
/* A funny way to budget for truncation node */
req.dirtied_ino_d = UBIFS_TRUN_NODE_SZ;
err = ubifs_budget_space(c, &req);
- if (err)
- return err;
+ if (err) {
+ /*
+ * Treat truncations to zero as deletion and always allow them,
+ * just like we do for '->unlink()'.
+ */
+ if (new_size || err != -ENOSPC)
+ return err;
+ budgeted = 0;
+ }
err = vmtruncate(inode, new_size);
if (err)
@@ -869,7 +876,12 @@ static int do_truncation(struct ubifs_info *c, struct inode *inode,
err = ubifs_jnl_truncate(c, inode, old_size, new_size);
mutex_unlock(&ui->ui_mutex);
out_budg:
- ubifs_release_budget(c, &req);
+ if (budgeted)
+ ubifs_release_budget(c, &req);
+ else {
+ c->nospace = c->nospace_rp = 0;
+ smp_wmb();
+ }
return err;
}
diff --git a/fs/ubifs/find.c b/fs/ubifs/find.c
index adee7b5ddeab..47814cde2407 100644
--- a/fs/ubifs/find.c
+++ b/fs/ubifs/find.c
@@ -211,14 +211,8 @@ static const struct ubifs_lprops *scan_for_dirty(struct ubifs_info *c,
* dirty index heap, and it falls-back to LPT scanning if the heaps are empty
* or do not have an LEB which satisfies the @min_space criteria.
*
- * Note:
- * o LEBs which have less than dead watermark of dirty space are never picked
- * by this function;
- *
- * Returns zero and the LEB properties of
- * found dirty LEB in case of success, %-ENOSPC if no dirty LEB was found and a
- * negative error code in case of other failures. The returned LEB is marked as
- * "taken".
+ * Note, LEBs which have less than dead watermark of free + dirty space are
+ * never picked by this function.
*
* The additional @pick_free argument controls if this function has to return a
* free or freeable LEB if one is present. For example, GC must to set it to %1,
@@ -231,6 +225,10 @@ static const struct ubifs_lprops *scan_for_dirty(struct ubifs_info *c,
*
* In addition @pick_free is set to %2 by the recovery process in order to
* recover gc_lnum in which case an index LEB must not be returned.
+ *
+ * This function returns zero and the LEB properties of found dirty LEB in case
+ * of success, %-ENOSPC if no dirty LEB was found and a negative error code in
+ * case of other failures. The returned LEB is marked as "taken".
*/
int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
int min_space, int pick_free)
@@ -245,7 +243,7 @@ int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
int lebs, rsvd_idx_lebs = 0;
spin_lock(&c->space_lock);
- lebs = c->lst.empty_lebs;
+ lebs = c->lst.empty_lebs + c->idx_gc_cnt;
lebs += c->freeable_cnt - c->lst.taken_empty_lebs;
/*
@@ -317,7 +315,7 @@ int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
lp = idx_lp;
if (lp) {
- ubifs_assert(lp->dirty >= c->dead_wm);
+ ubifs_assert(lp->free + lp->dirty >= c->dead_wm);
goto found;
}
@@ -509,7 +507,6 @@ int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free,
rsvd_idx_lebs = 0;
lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
c->lst.taken_empty_lebs;
- ubifs_assert(lebs + c->lst.idx_lebs >= c->min_idx_lebs);
if (rsvd_idx_lebs < lebs)
/*
* OK to allocate an empty LEB, but we still don't want to go
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index d0f3dac29081..02aba36fe3d4 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -334,15 +334,21 @@ int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
err = move_nodes(c, sleb);
if (err)
- goto out;
+ goto out_inc_seq;
err = gc_sync_wbufs(c);
if (err)
- goto out;
+ goto out_inc_seq;
err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, 0, 0);
if (err)
- goto out;
+ goto out_inc_seq;
+
+ /* Allow for races with TNC */
+ c->gced_lnum = lnum;
+ smp_wmb();
+ c->gc_seq += 1;
+ smp_wmb();
if (c->gc_lnum == -1) {
c->gc_lnum = lnum;
@@ -363,6 +369,14 @@ int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
out:
ubifs_scan_destroy(sleb);
return err;
+
+out_inc_seq:
+ /* We may have moved at least some nodes so allow for races with TNC */
+ c->gced_lnum = lnum;
+ smp_wmb();
+ c->gc_seq += 1;
+ smp_wmb();
+ goto out;
}
/**
diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h
index 87dabf9fe742..4c12a9215d7f 100644
--- a/fs/ubifs/misc.h
+++ b/fs/ubifs/misc.h
@@ -284,38 +284,6 @@ static inline void *ubifs_idx_key(const struct ubifs_info *c,
}
/**
- * ubifs_reported_space - calculate reported free space.
- * @c: the UBIFS file-system description object
- * @free: amount of free space
- *
- * This function calculates amount of free space which will be reported to
- * user-space. User-space application tend to expect that if the file-system
- * (e.g., via the 'statfs()' call) reports that it has N bytes available, they
- * are able to write a file of size N. UBIFS attaches node headers to each data
- * node and it has to write indexind nodes as well. This introduces additional
- * overhead, and UBIFS it has to report sligtly less free space to meet the
- * above expectetion.
- *
- * This function assumes free space is made up of uncompressed data nodes and
- * full index nodes (one per data node, doubled because we always allow enough
- * space to write the index twice).
- *
- * Note, the calculation is pessimistic, which means that most of the time
- * UBIFS reports less space than it actually has.
- */
-static inline long long ubifs_reported_space(const struct ubifs_info *c,
- uint64_t free)
-{
- int divisor, factor;
-
- divisor = UBIFS_MAX_DATA_NODE_SZ + (c->max_idx_node_sz * 3);
- factor = UBIFS_MAX_DATA_NODE_SZ - UBIFS_DATA_NODE_SZ;
- do_div(free, divisor);
-
- return free * factor;
-}
-
-/**
* ubifs_current_time - round current time to time granularity.
* @inode: inode
*/
@@ -325,4 +293,21 @@ static inline struct timespec ubifs_current_time(struct inode *inode)
current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
}
+/**
+ * ubifs_tnc_lookup - look up a file-system node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ *
+ * This function look up and reads node with key @key. The caller has to make
+ * sure the @node buffer is large enough to fit the node. Returns zero in case
+ * of success, %-ENOENT if the node was not found, and a negative error code in
+ * case of failure.
+ */
+static inline int ubifs_tnc_lookup(struct ubifs_info *c,
+ const union ubifs_key *key, void *node)
+{
+ return ubifs_tnc_locate(c, key, node, NULL, NULL);
+}
+
#endif /* __UBIFS_MISC_H__ */
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index f71e6b8822c4..3f4902060c7a 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -370,8 +370,9 @@ static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct ubifs_info *c = dentry->d_sb->s_fs_info;
unsigned long long free;
+ __le32 *uuid = (__le32 *)c->uuid;
- free = ubifs_budg_get_free_space(c);
+ free = ubifs_get_free_space(c);
dbg_gen("free space %lld bytes (%lld blocks)",
free, free >> UBIFS_BLOCK_SHIFT);
@@ -386,7 +387,8 @@ static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_files = 0;
buf->f_ffree = 0;
buf->f_namelen = UBIFS_MAX_NLEN;
-
+ buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]);
+ buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]);
return 0;
}
@@ -530,6 +532,12 @@ static int init_constants_early(struct ubifs_info *c)
c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
+ /*
+ * Calculate how many bytes would be wasted at the end of LEB if it was
+ * fully filled with data nodes of maximum size. This is used in
+ * calculations when reporting free space.
+ */
+ c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
return 0;
}
@@ -647,13 +655,11 @@ static int init_constants_late(struct ubifs_info *c)
* internally because it does not make much sense for UBIFS, but it is
* necessary to report something for the 'statfs()' call.
*
- * Subtract the LEB reserved for GC and the LEB which is reserved for
- * deletions.
- *
- * Review 'ubifs_calc_available()' if changing this calculation.
+ * Subtract the LEB reserved for GC, the LEB which is reserved for
+ * deletions, and assume only one journal head is available.
*/
- tmp64 = c->main_lebs - 2;
- tmp64 *= (uint64_t)c->leb_size - c->dark_wm;
+ tmp64 = c->main_lebs - 2 - c->jhead_cnt + 1;
+ tmp64 *= (uint64_t)c->leb_size - c->leb_overhead;
tmp64 = ubifs_reported_space(c, tmp64);
c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
@@ -1018,14 +1024,13 @@ static int mount_ubifs(struct ubifs_info *c)
goto out_dereg;
}
+ sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
if (!mounted_read_only) {
err = alloc_wbufs(c);
if (err)
goto out_cbuf;
/* Create background thread */
- sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num,
- c->vi.vol_id);
c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
if (!c->bgt)
c->bgt = ERR_PTR(-EINVAL);
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index e909f4a96443..7634c5970887 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -506,7 +506,7 @@ static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key,
if (keys_cmp(c, key, &node_key) != 0)
ret = 0;
}
- if (ret == 0)
+ if (ret == 0 && c->replaying)
dbg_mnt("dangling branch LEB %d:%d len %d, key %s",
zbr->lnum, zbr->offs, zbr->len, DBGKEY(key));
return ret;
@@ -1382,50 +1382,39 @@ static int lookup_level0_dirty(struct ubifs_info *c, const union ubifs_key *key,
}
/**
- * ubifs_tnc_lookup - look up a file-system node.
+ * maybe_leb_gced - determine if a LEB may have been garbage collected.
* @c: UBIFS file-system description object
- * @key: node key to lookup
- * @node: the node is returned here
+ * @lnum: LEB number
+ * @gc_seq1: garbage collection sequence number
*
- * This function look up and reads node with key @key. The caller has to make
- * sure the @node buffer is large enough to fit the node. Returns zero in case
- * of success, %-ENOENT if the node was not found, and a negative error code in
- * case of failure.
+ * This function determines if @lnum may have been garbage collected since
+ * sequence number @gc_seq1. If it may have been then %1 is returned, otherwise
+ * %0 is returned.
*/
-int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
- void *node)
+static int maybe_leb_gced(struct ubifs_info *c, int lnum, int gc_seq1)
{
- int found, n, err;
- struct ubifs_znode *znode;
- struct ubifs_zbranch zbr, *zt;
+ int gc_seq2, gced_lnum;
- mutex_lock(&c->tnc_mutex);
- found = ubifs_lookup_level0(c, key, &znode, &n);
- if (!found) {
- err = -ENOENT;
- goto out;
- } else if (found < 0) {
- err = found;
- goto out;
- }
- zt = &znode->zbranch[n];
- if (is_hash_key(c, key)) {
- /*
- * In this case the leaf node cache gets used, so we pass the
- * address of the zbranch and keep the mutex locked
- */
- err = tnc_read_node_nm(c, zt, node);
- goto out;
- }
- zbr = znode->zbranch[n];
- mutex_unlock(&c->tnc_mutex);
-
- err = ubifs_tnc_read_node(c, &zbr, node);
- return err;
-
-out:
- mutex_unlock(&c->tnc_mutex);
- return err;
+ gced_lnum = c->gced_lnum;
+ smp_rmb();
+ gc_seq2 = c->gc_seq;
+ /* Same seq means no GC */
+ if (gc_seq1 == gc_seq2)
+ return 0;
+ /* Different by more than 1 means we don't know */
+ if (gc_seq1 + 1 != gc_seq2)
+ return 1;
+ /*
+ * We have seen the sequence number has increased by 1. Now we need to
+ * be sure we read the right LEB number, so read it again.
+ */
+ smp_rmb();
+ if (gced_lnum != c->gced_lnum)
+ return 1;
+ /* Finally we can check lnum */
+ if (gced_lnum == lnum)
+ return 1;
+ return 0;
}
/**
@@ -1436,16 +1425,19 @@ out:
* @lnum: LEB number is returned here
* @offs: offset is returned here
*
- * This function is the same as 'ubifs_tnc_lookup()' but it returns the node
- * location also. See 'ubifs_tnc_lookup()'.
+ * This function look up and reads node with key @key. The caller has to make
+ * sure the @node buffer is large enough to fit the node. Returns zero in case
+ * of success, %-ENOENT if the node was not found, and a negative error code in
+ * case of failure. The node location can be returned in @lnum and @offs.
*/
int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
void *node, int *lnum, int *offs)
{
- int found, n, err;
+ int found, n, err, safely = 0, gc_seq1;
struct ubifs_znode *znode;
struct ubifs_zbranch zbr, *zt;
+again:
mutex_lock(&c->tnc_mutex);
found = ubifs_lookup_level0(c, key, &znode, &n);
if (!found) {
@@ -1456,24 +1448,43 @@ int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
goto out;
}
zt = &znode->zbranch[n];
+ if (lnum) {
+ *lnum = zt->lnum;
+ *offs = zt->offs;
+ }
if (is_hash_key(c, key)) {
/*
* In this case the leaf node cache gets used, so we pass the
* address of the zbranch and keep the mutex locked
*/
- *lnum = zt->lnum;
- *offs = zt->offs;
err = tnc_read_node_nm(c, zt, node);
goto out;
}
+ if (safely) {
+ err = ubifs_tnc_read_node(c, zt, node);
+ goto out;
+ }
+ /* Drop the TNC mutex prematurely and race with garbage collection */
zbr = znode->zbranch[n];
+ gc_seq1 = c->gc_seq;
mutex_unlock(&c->tnc_mutex);
- *lnum = zbr.lnum;
- *offs = zbr.offs;
+ if (ubifs_get_wbuf(c, zbr.lnum)) {
+ /* We do not GC journal heads */
+ err = ubifs_tnc_read_node(c, &zbr, node);
+ return err;
+ }
- err = ubifs_tnc_read_node(c, &zbr, node);
- return err;
+ err = fallible_read_node(c, key, &zbr, node);
+ if (err <= 0 || maybe_leb_gced(c, zbr.lnum, gc_seq1)) {
+ /*
+ * The node may have been GC'ed out from under us so try again
+ * while keeping the TNC mutex locked.
+ */
+ safely = 1;
+ goto again;
+ }
+ return 0;
out:
mutex_unlock(&c->tnc_mutex);
@@ -1498,7 +1509,6 @@ static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
{
int found, n, err;
struct ubifs_znode *znode;
- struct ubifs_zbranch zbr;
dbg_tnc("name '%.*s' key %s", nm->len, nm->name, DBGKEY(key));
mutex_lock(&c->tnc_mutex);
@@ -1522,11 +1532,7 @@ static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
goto out_unlock;
}
- zbr = znode->zbranch[n];
- mutex_unlock(&c->tnc_mutex);
-
- err = tnc_read_node_nm(c, &zbr, node);
- return err;
+ err = tnc_read_node_nm(c, &znode->zbranch[n], node);
out_unlock:
mutex_unlock(&c->tnc_mutex);
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
index bd2121f3426e..a9ecbd9af20d 100644
--- a/fs/ubifs/ubifs-media.h
+++ b/fs/ubifs/ubifs-media.h
@@ -87,7 +87,7 @@
#define UBIFS_SK_LEN 8
/* Minimum index tree fanout */
-#define UBIFS_MIN_FANOUT 2
+#define UBIFS_MIN_FANOUT 3
/* Maximum number of levels in UBIFS indexing B-tree */
#define UBIFS_MAX_LEVELS 512
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index d7f706f7a302..17c620b93eec 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -995,6 +995,9 @@ struct ubifs_mount_opts {
* @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
* @max_inode_sz: maximum possible inode size in bytes
* @max_znode_sz: size of znode in bytes
+ *
+ * @leb_overhead: how many bytes are wasted in an LEB when it is filled with
+ * data nodes of maximum size - used in free space reporting
* @dead_wm: LEB dead space watermark
* @dark_wm: LEB dark space watermark
* @block_cnt: count of 4KiB blocks on the FS
@@ -1028,6 +1031,8 @@ struct ubifs_mount_opts {
* @sbuf: a buffer of LEB size used by GC and replay for scanning
* @idx_gc: list of index LEBs that have been garbage collected
* @idx_gc_cnt: number of elements on the idx_gc list
+ * @gc_seq: incremented for every non-index LEB garbage collected
+ * @gced_lnum: last non-index LEB that was garbage collected
*
* @infos_list: links all 'ubifs_info' objects
* @umount_mutex: serializes shrinker and un-mount
@@ -1224,6 +1229,8 @@ struct ubifs_info {
int max_idx_node_sz;
long long max_inode_sz;
int max_znode_sz;
+
+ int leb_overhead;
int dead_wm;
int dark_wm;
int block_cnt;
@@ -1257,6 +1264,8 @@ struct ubifs_info {
void *sbuf;
struct list_head idx_gc;
int idx_gc_cnt;
+ volatile int gc_seq;
+ volatile int gced_lnum;
struct list_head infos_list;
struct mutex umount_mutex;
@@ -1434,9 +1443,10 @@ void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
struct ubifs_budget_req *req);
void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
struct ubifs_budget_req *req);
-long long ubifs_budg_get_free_space(struct ubifs_info *c);
+long long ubifs_get_free_space(struct ubifs_info *c);
int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
void ubifs_convert_page_budget(struct ubifs_info *c);
+long long ubifs_reported_space(const struct ubifs_info *c, uint64_t free);
long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs);
/* find.c */
@@ -1451,8 +1461,6 @@ int ubifs_save_dirty_idx_lnums(struct ubifs_info *c);
/* tnc.c */
int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
struct ubifs_znode **zn, int *n);
-int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
- void *node);
int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
void *node, const struct qstr *nm);
int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,