1 files changed, 342 insertions, 42 deletions

diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index 28e492e4ec88..687b28713c32 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -28,6 +28,7 @@
 #include <linux/slab.h>
 #include <linux/highmem.h>
 #include <linux/bitops.h>
+#include <linux/debugfs.h>
 
 #define MLOG_MASK_PREFIX ML_DISK_ALLOC
 #include <cluster/masklog.h>
@@ -47,8 +48,6 @@
 
 #define OCFS2_LOCAL_ALLOC(dinode)       (&((dinode)->id2.i_lab))
 
-static inline int ocfs2_local_alloc_window_bits(struct ocfs2_super *osb);
-
 static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc);
 
 static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
@@ -75,24 +74,129 @@ static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
 static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
                                           struct inode *local_alloc_inode);
 
-static inline int ocfs2_local_alloc_window_bits(struct ocfs2_super *osb)
+#ifdef CONFIG_OCFS2_FS_STATS
+
+static int ocfs2_la_debug_open(struct inode *inode, struct file *file)
+{
+        file->private_data = inode->i_private;
+        return 0;
+}
+
+#define LA_DEBUG_BUF_SZ PAGE_CACHE_SIZE
+#define LA_DEBUG_VER    1
+static ssize_t ocfs2_la_debug_read(struct file *file, char __user *userbuf,
+                                   size_t count, loff_t *ppos)
+{
+        static DEFINE_MUTEX(la_debug_mutex);
+        struct ocfs2_super *osb = file->private_data;
+        int written, ret;
+        char *buf = osb->local_alloc_debug_buf;
+
+        mutex_lock(&la_debug_mutex);
+        memset(buf, 0, LA_DEBUG_BUF_SZ);
+
+        written = snprintf(buf, LA_DEBUG_BUF_SZ,
+                           "0x%x\t0x%llx\t%u\t%u\t0x%x\n",
+                           LA_DEBUG_VER,
+                           (unsigned long long)osb->la_last_gd,
+                           osb->local_alloc_default_bits,
+                           osb->local_alloc_bits, osb->local_alloc_state);
+
+        ret = simple_read_from_buffer(userbuf, count, ppos, buf, written);
+
+        mutex_unlock(&la_debug_mutex);
+        return ret;
+}
+
+static const struct file_operations ocfs2_la_debug_fops = {
+        .open =         ocfs2_la_debug_open,
+        .read =         ocfs2_la_debug_read,
+};
+
+static void ocfs2_init_la_debug(struct ocfs2_super *osb)
+{
+        osb->local_alloc_debug_buf = kmalloc(LA_DEBUG_BUF_SZ, GFP_NOFS);
+        if (!osb->local_alloc_debug_buf)
+                return;
+
+        osb->local_alloc_debug = debugfs_create_file("local_alloc_stats",
+                                                     S_IFREG|S_IRUSR,
+                                                     osb->osb_debug_root,
+                                                     osb,
+                                                     &ocfs2_la_debug_fops);
+        if (!osb->local_alloc_debug) {
+                kfree(osb->local_alloc_debug_buf);
+                osb->local_alloc_debug_buf = NULL;
+        }
+}
+
+static void ocfs2_shutdown_la_debug(struct ocfs2_super *osb)
+{
+        if (osb->local_alloc_debug)
+                debugfs_remove(osb->local_alloc_debug);
+
+        if (osb->local_alloc_debug_buf)
+                kfree(osb->local_alloc_debug_buf);
+
+        osb->local_alloc_debug_buf = NULL;
+        osb->local_alloc_debug = NULL;
+}
+#else   /* CONFIG_OCFS2_FS_STATS */
+static void ocfs2_init_la_debug(struct ocfs2_super *osb)
+{
+        return;
+}
+static void ocfs2_shutdown_la_debug(struct ocfs2_super *osb)
+{
+        return;
+}
+#endif
+
+static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb)
 {
-        BUG_ON(osb->s_clustersize_bits > 20);
+        return (osb->local_alloc_state == OCFS2_LA_THROTTLED ||
+                osb->local_alloc_state == OCFS2_LA_ENABLED);
+}
 
-        /* Size local alloc windows by the megabyte */
-        return osb->local_alloc_size << (20 - osb->s_clustersize_bits);
+void ocfs2_local_alloc_seen_free_bits(struct ocfs2_super *osb,
+                                      unsigned int num_clusters)
+{
+        spin_lock(&osb->osb_lock);
+        if (osb->local_alloc_state == OCFS2_LA_DISABLED ||
+            osb->local_alloc_state == OCFS2_LA_THROTTLED)
+                if (num_clusters >= osb->local_alloc_default_bits) {
+                        cancel_delayed_work(&osb->la_enable_wq);
+                        osb->local_alloc_state = OCFS2_LA_ENABLED;
+                }
+        spin_unlock(&osb->osb_lock);
+}
+
+void ocfs2_la_enable_worker(struct work_struct *work)
+{
+        struct ocfs2_super *osb =
+                container_of(work, struct ocfs2_super,
+                             la_enable_wq.work);
+        spin_lock(&osb->osb_lock);
+        osb->local_alloc_state = OCFS2_LA_ENABLED;
+        spin_unlock(&osb->osb_lock);
 }
 
 /*
  * Tell us whether a given allocation should use the local alloc
  * file. Otherwise, it has to go to the main bitmap.
+ *
+ * This function does semi-dirty reads of local alloc size and state!
+ * This is ok however, as the values are re-checked once under mutex.
  */
 int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits)
 {
-        int la_bits = ocfs2_local_alloc_window_bits(osb);
         int ret = 0;
+        int la_bits;
+
+        spin_lock(&osb->osb_lock);
+        la_bits = osb->local_alloc_bits;
 
-        if (osb->local_alloc_state != OCFS2_LA_ENABLED)
+        if (!ocfs2_la_state_enabled(osb))
                 goto bail;
 
         /* la_bits should be at least twice the size (in clusters) of
@@ -106,6 +210,7 @@ int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits)
 bail:
         mlog(0, "state=%d, bits=%llu, la_bits=%d, ret=%d\n",
              osb->local_alloc_state, (unsigned long long)bits, la_bits, ret);
+        spin_unlock(&osb->osb_lock);
         return ret;
 }
 
@@ -120,14 +225,18 @@ int ocfs2_load_local_alloc(struct ocfs2_super *osb)
 
         mlog_entry_void();
 
-        if (osb->local_alloc_size == 0)
+        ocfs2_init_la_debug(osb);
+
+        if (osb->local_alloc_bits == 0)
                 goto bail;
 
-        if (ocfs2_local_alloc_window_bits(osb) >= osb->bitmap_cpg) {
+        if (osb->local_alloc_bits >= osb->bitmap_cpg) {
                 mlog(ML_NOTICE, "Requested local alloc window %d is larger "
                      "than max possible %u. Using defaults.\n",
-                     ocfs2_local_alloc_window_bits(osb), (osb->bitmap_cpg - 1));
-                osb->local_alloc_size = OCFS2_DEFAULT_LOCAL_ALLOC_SIZE;
+                     osb->local_alloc_bits, (osb->bitmap_cpg - 1));
+                osb->local_alloc_bits =
+                        ocfs2_megabytes_to_clusters(osb->sb,
+                                                    OCFS2_DEFAULT_LOCAL_ALLOC_SIZE);
         }
 
         /* read the alloc off disk */
@@ -139,8 +248,8 @@ int ocfs2_load_local_alloc(struct ocfs2_super *osb)
                 goto bail;
         }
 
-        status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno,
-                                  &alloc_bh, 0, inode);
+        status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1,
+                                   &alloc_bh, OCFS2_BH_IGNORE_CACHE);
         if (status < 0) {
                 mlog_errno(status);
                 goto bail;
@@ -185,13 +294,14 @@ int ocfs2_load_local_alloc(struct ocfs2_super *osb)
 
 bail:
         if (status < 0)
-                if (alloc_bh)
-                        brelse(alloc_bh);
+                brelse(alloc_bh);
         if (inode)
                 iput(inode);
 
-        mlog(0, "Local alloc window bits = %d\n",
-             ocfs2_local_alloc_window_bits(osb));
+        if (status < 0)
+                ocfs2_shutdown_la_debug(osb);
+
+        mlog(0, "Local alloc window bits = %d\n", osb->local_alloc_bits);
 
         mlog_exit(status);
         return status;
@@ -217,6 +327,11 @@ void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb)
 
         mlog_entry_void();
 
+        cancel_delayed_work(&osb->la_enable_wq);
+        flush_workqueue(ocfs2_wq);
+
+        ocfs2_shutdown_la_debug(osb);
+
         if (osb->local_alloc_state == OCFS2_LA_UNUSED)
                 goto out;
 
@@ -295,8 +410,7 @@ out_commit:
         ocfs2_commit_trans(osb, handle);
 
 out_unlock:
-        if (main_bm_bh)
-                brelse(main_bm_bh);
+        brelse(main_bm_bh);
 
         ocfs2_inode_unlock(main_bm_inode, 1);
 
@@ -345,8 +459,8 @@ int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb,
 
         mutex_lock(&inode->i_mutex);
 
-        status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno,
-                                  &alloc_bh, 0, inode);
+        status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1,
+                                   &alloc_bh, OCFS2_BH_IGNORE_CACHE);
         if (status < 0) {
                 mlog_errno(status);
                 goto bail;
@@ -372,8 +486,7 @@ bail:
                 *alloc_copy = NULL;
         }
 
-        if (alloc_bh)
-                brelse(alloc_bh);
+        brelse(alloc_bh);
 
         if (inode) {
                 mutex_unlock(&inode->i_mutex);
@@ -441,8 +554,7 @@ out_unlock:
 out_mutex:
         mutex_unlock(&main_bm_inode->i_mutex);
 
-        if (main_bm_bh)
-                brelse(main_bm_bh);
+        brelse(main_bm_bh);
 
         iput(main_bm_inode);
 
@@ -453,8 +565,48 @@ out:
         return status;
 }
 
+/* Check to see if the local alloc window is within ac->ac_max_block */
+static int ocfs2_local_alloc_in_range(struct inode *inode,
+                                      struct ocfs2_alloc_context *ac,
+                                      u32 bits_wanted)
+{
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+        struct ocfs2_dinode *alloc;
+        struct ocfs2_local_alloc *la;
+        int start;
+        u64 block_off;
+
+        if (!ac->ac_max_block)
+                return 1;
+
+        alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
+        la = OCFS2_LOCAL_ALLOC(alloc);
+
+        start = ocfs2_local_alloc_find_clear_bits(osb, alloc, bits_wanted);
+        if (start == -1) {
+                mlog_errno(-ENOSPC);
+                return 0;
+        }
+
+        /*
+         * Converting (bm_off + start + bits_wanted) to blocks gives us
+         * the blkno just past our actual allocation.  This is perfect
+         * to compare with ac_max_block.
+         */
+        block_off = ocfs2_clusters_to_blocks(inode->i_sb,
+                                             le32_to_cpu(la->la_bm_off) +
+                                             start + bits_wanted);
+        mlog(0, "Checking %llu against %llu\n",
+             (unsigned long long)block_off,
+             (unsigned long long)ac->ac_max_block);
+        if (block_off > ac->ac_max_block)
+                return 0;
+
+        return 1;
+}
+
 /*
- * make sure we've got at least bitswanted contiguous bits in the
+ * make sure we've got at least bits_wanted contiguous bits in the
  * local alloc. You lose them when you drop i_mutex.
  *
  * We will add ourselves to the transaction passed in, but may start
@@ -485,16 +637,18 @@ int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb,
 
         mutex_lock(&local_alloc_inode->i_mutex);
 
-        if (osb->local_alloc_state != OCFS2_LA_ENABLED) {
-                status = -ENOSPC;
-                goto bail;
-        }
-
-        if (bits_wanted > ocfs2_local_alloc_window_bits(osb)) {
-                mlog(0, "Asking for more than my max window size!\n");
+        /*
+         * We must double check state and allocator bits because
+         * another process may have changed them while holding i_mutex.
+         */
+        spin_lock(&osb->osb_lock);
+        if (!ocfs2_la_state_enabled(osb) ||
+            (bits_wanted > osb->local_alloc_bits)) {
+                spin_unlock(&osb->osb_lock);
                 status = -ENOSPC;
                 goto bail;
         }
+        spin_unlock(&osb->osb_lock);
 
         alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 
@@ -522,6 +676,36 @@ int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb,
                                 mlog_errno(status);
                         goto bail;
                 }
+
+                /*
+                 * Under certain conditions, the window slide code
+                 * might have reduced the number of bits available or
+                 * disabled the the local alloc entirely. Re-check
+                 * here and return -ENOSPC if necessary.
+                 */
+                status = -ENOSPC;
+                if (!ocfs2_la_state_enabled(osb))
+                        goto bail;
+
+                free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) -
+                        le32_to_cpu(alloc->id1.bitmap1.i_used);
+                if (bits_wanted > free_bits)
+                        goto bail;
+        }
+
+        if (ac->ac_max_block)
+                mlog(0, "Calling in_range for max block %llu\n",
+                     (unsigned long long)ac->ac_max_block);
+
+        if (!ocfs2_local_alloc_in_range(local_alloc_inode, ac,
+                                        bits_wanted)) {
+                /*
+                 * The window is outside ac->ac_max_block.
+                 * This errno tells the caller to keep localalloc enabled
+                 * but to get the allocation from the main bitmap.
+                 */
+                status = -EFBIG;
+                goto bail;
         }
 
         ac->ac_inode = local_alloc_inode;
@@ -789,6 +973,85 @@ bail:
         return status;
 }
 
+enum ocfs2_la_event {
+        OCFS2_LA_EVENT_SLIDE,           /* Normal window slide. */
+        OCFS2_LA_EVENT_FRAGMENTED,      /* The global bitmap has
+                                         * enough bits theoretically
+                                         * free, but a contiguous
+                                         * allocation could not be
+                                         * found. */
+        OCFS2_LA_EVENT_ENOSPC,          /* Global bitmap doesn't have
+                                         * enough bits free to satisfy
+                                         * our request. */
+};
+#define OCFS2_LA_ENABLE_INTERVAL (30 * HZ)
+/*
+ * Given an event, calculate the size of our next local alloc window.
+ *
+ * This should always be called under i_mutex of the local alloc inode
+ * so that local alloc disabling doesn't race with processes trying to
+ * use the allocator.
+ *
+ * Returns the state which the local alloc was left in. This value can
+ * be ignored by some paths.
+ */
+static int ocfs2_recalc_la_window(struct ocfs2_super *osb,
+                                  enum ocfs2_la_event event)
+{
+        unsigned int bits;
+        int state;
+
+        spin_lock(&osb->osb_lock);
+        if (osb->local_alloc_state == OCFS2_LA_DISABLED) {
+                WARN_ON_ONCE(osb->local_alloc_state == OCFS2_LA_DISABLED);
+                goto out_unlock;
+        }
+
+        /*
+         * ENOSPC and fragmentation are treated similarly for now.
+         */
+        if (event == OCFS2_LA_EVENT_ENOSPC ||
+            event == OCFS2_LA_EVENT_FRAGMENTED) {
+                /*
+                 * We ran out of contiguous space in the primary
+                 * bitmap. Drastically reduce the number of bits used
+                 * by local alloc until we have to disable it.
+                 */
+                bits = osb->local_alloc_bits >> 1;
+                if (bits > ocfs2_megabytes_to_clusters(osb->sb, 1)) {
+                        /*
+                         * By setting state to THROTTLED, we'll keep
+                         * the number of local alloc bits used down
+                         * until an event occurs which would give us
+                         * reason to assume the bitmap situation might
+                         * have changed.
+                         */
+                        osb->local_alloc_state = OCFS2_LA_THROTTLED;
+                        osb->local_alloc_bits = bits;
+                } else {
+                        osb->local_alloc_state = OCFS2_LA_DISABLED;
+                }
+                queue_delayed_work(ocfs2_wq, &osb->la_enable_wq,
+                                   OCFS2_LA_ENABLE_INTERVAL);
+                goto out_unlock;
+        }
+
+        /*
+         * Don't increase the size of the local alloc window until we
+         * know we might be able to fulfill the request. Otherwise, we
+         * risk bouncing around the global bitmap during periods of
+         * low space.
+         */
+        if (osb->local_alloc_state != OCFS2_LA_THROTTLED)
+                osb->local_alloc_bits = osb->local_alloc_default_bits;
+
+out_unlock:
+        state = osb->local_alloc_state;
+        spin_unlock(&osb->osb_lock);
+
+        return state;
+}
+
 static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
                                                 struct ocfs2_alloc_context **ac,
                                                 struct inode **bitmap_inode,
@@ -803,12 +1066,21 @@ static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
                 goto bail;
         }
 
-        (*ac)->ac_bits_wanted = ocfs2_local_alloc_window_bits(osb);
+retry_enospc:
+        (*ac)->ac_bits_wanted = osb->local_alloc_bits;
 
         status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
+        if (status == -ENOSPC) {
+                if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_ENOSPC) ==
+                    OCFS2_LA_DISABLED)
+                        goto bail;
+
+                ocfs2_free_ac_resource(*ac);
+                memset(*ac, 0, sizeof(struct ocfs2_alloc_context));
+                goto retry_enospc;
+        }
         if (status < 0) {
-                if (status != -ENOSPC)
-                        mlog_errno(status);
+                mlog_errno(status);
                 goto bail;
         }
 
@@ -849,7 +1121,7 @@ static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
                      "one\n");
 
         mlog(0, "Allocating %u clusters for a new window.\n",
-             ocfs2_local_alloc_window_bits(osb));
+             osb->local_alloc_bits);
 
         /* Instruct the allocation code to try the most recently used
          * cluster group. We'll re-record the group used this pass
@@ -859,9 +1131,36 @@ static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
         /* we used the generic suballoc reserve function, but we set
          * everything up nicely, so there's no reason why we can't use
          * the more specific cluster api to claim bits. */
-        status = ocfs2_claim_clusters(osb, handle, ac,
-                                      ocfs2_local_alloc_window_bits(osb),
+        status = ocfs2_claim_clusters(osb, handle, ac, osb->local_alloc_bits,
                                       &cluster_off, &cluster_count);
+        if (status == -ENOSPC) {
+retry_enospc:
+                /*
+                 * Note: We could also try syncing the journal here to
+                 * allow use of any free bits which the current
+                 * transaction can't give us access to. --Mark
+                 */
+                if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_FRAGMENTED) ==
+                    OCFS2_LA_DISABLED)
+                        goto bail;
+
+                status = ocfs2_claim_clusters(osb, handle, ac,
+                                              osb->local_alloc_bits,
+                                              &cluster_off,
+                                              &cluster_count);
+                if (status == -ENOSPC)
+                        goto retry_enospc;
+                /*
+                 * We only shrunk the *minimum* number of in our
+                 * request - it's entirely possible that the allocator
+                 * might give us more than we asked for.
+                 */
+                if (status == 0) {
+                        spin_lock(&osb->osb_lock);
+                        osb->local_alloc_bits = cluster_count;
+                        spin_unlock(&osb->osb_lock);
+                }
+        }
         if (status < 0) {
                 if (status != -ENOSPC)
                         mlog_errno(status);
@@ -905,6 +1204,8 @@ static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
 
         mlog_entry_void();
 
+        ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_SLIDE);
+
         /* This will lock the main bitmap for us. */
         status = ocfs2_local_alloc_reserve_for_window(osb,
                                                       &ac,
@@ -976,8 +1277,7 @@ bail:
         if (handle)
                 ocfs2_commit_trans(osb, handle);
 
-        if (main_bm_bh)
-                brelse(main_bm_bh);
+        brelse(main_bm_bh);
 
         if (main_bm_inode)
                 iput(main_bm_inode);