1 files changed, 110 insertions, 58 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 14f8e1faa46e..0e92e5763005 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -52,6 +52,7 @@
 #include "locking.h"
 #include "inode-map.h"
 #include "backref.h"
+#include "rcu-string.h"
 
 /* Mask out flags that are inappropriate for the given type of inode. */
 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
@@ -261,6 +262,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
         }
 
         btrfs_update_iflags(inode);
+        inode_inc_iversion(inode);
         inode->i_ctime = CURRENT_TIME;
         ret = btrfs_update_inode(trans, root, inode);
 
@@ -367,7 +369,7 @@ static noinline int create_subvol(struct btrfs_root *root,
                 return PTR_ERR(trans);
 
         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
-                                      0, objectid, NULL, 0, 0, 0, 0);
+                                      0, objectid, NULL, 0, 0, 0);
         if (IS_ERR(leaf)) {
                 ret = PTR_ERR(leaf);
                 goto fail;
@@ -784,39 +786,57 @@ none:
         return -ENOENT;
 }
 
-/*
- * Validaty check of prev em and next em:
- * 1) no prev/next em
- * 2) prev/next em is an hole/inline extent
- */
-static int check_adjacent_extents(struct inode *inode, struct extent_map *em)
+static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 {
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-        struct extent_map *prev = NULL, *next = NULL;
-        int ret = 0;
+        struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+        struct extent_map *em;
+        u64 len = PAGE_CACHE_SIZE;
 
+        /*
+         * hopefully we have this extent in the tree already, try without
+         * the full extent lock
+         */
         read_lock(&em_tree->lock);
-        prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1);
-        next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1);
+        em = lookup_extent_mapping(em_tree, start, len);
         read_unlock(&em_tree->lock);
 
-        if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) &&
-            (!next || next->block_start >= EXTENT_MAP_LAST_BYTE))
-                ret = 1;
-        free_extent_map(prev);
-        free_extent_map(next);
+        if (!em) {
+                /* get the big lock and read metadata off disk */
+                lock_extent(io_tree, start, start + len - 1);
+                em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
+                unlock_extent(io_tree, start, start + len - 1);
+
+                if (IS_ERR(em))
+                        return NULL;
+        }
+
+        return em;
+}
 
+static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
+{
+        struct extent_map *next;
+        bool ret = true;
+
+        /* this is the last extent */
+        if (em->start + em->len >= i_size_read(inode))
+                return false;
+
+        next = defrag_lookup_extent(inode, em->start + em->len);
+        if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
+                ret = false;
+
+        free_extent_map(next);
         return ret;
 }
 
-static int should_defrag_range(struct inode *inode, u64 start, u64 len,
-                               int thresh, u64 *last_len, u64 *skip,
-                               u64 *defrag_end)
+static int should_defrag_range(struct inode *inode, u64 start, int thresh,
+                               u64 *last_len, u64 *skip, u64 *defrag_end)
 {
-        struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-        struct extent_map *em = NULL;
-        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+        struct extent_map *em;
         int ret = 1;
+        bool next_mergeable = true;
 
         /*
          * make sure that once we start defragging an extent, we keep on
@@ -827,23 +847,9 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
 
         *skip = 0;
 
-        /*
-         * hopefully we have this extent in the tree already, try without
-         * the full extent lock
-         */
-        read_lock(&em_tree->lock);
-        em = lookup_extent_mapping(em_tree, start, len);
-        read_unlock(&em_tree->lock);
-
-        if (!em) {
-                /* get the big lock and read metadata off disk */
-                lock_extent(io_tree, start, start + len - 1);
-                em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
-                unlock_extent(io_tree, start, start + len - 1);
-
-                if (IS_ERR(em))
-                        return 0;
-        }
+        em = defrag_lookup_extent(inode, start);
+        if (!em)
+                return 0;
 
         /* this will cover holes, and inline extents */
         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
@@ -851,18 +857,15 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
                 goto out;
         }
 
-        /* If we have nothing to merge with us, just skip. */
-        if (check_adjacent_extents(inode, em)) {
-                ret = 0;
-                goto out;
-        }
+        next_mergeable = defrag_check_next_extent(inode, em);
 
         /*
-         * we hit a real extent, if it is big don't bother defragging it again
+         * we hit a real extent, if it is big or the next extent is not a
+         * real extent, don't bother defragging it
          */
-        if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
+        if ((*last_len == 0 || *last_len >= thresh) &&
+            (em->len >= thresh || !next_mergeable))
                 ret = 0;
-
 out:
         /*
          * last_len ends up being a counter of how many bytes we've defragged.
@@ -1141,8 +1144,8 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
                         break;
 
                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
-                                         PAGE_CACHE_SIZE, extent_thresh,
-                                         &last_len, &skip, &defrag_end)) {
+                                         extent_thresh, &last_len, &skip,
+                                         &defrag_end)) {
                         unsigned long next;
                         /*
                          * the should_defrag function tells us how much to skip
@@ -1303,6 +1306,14 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
                 ret = -EINVAL;
                 goto out_free;
         }
+        if (device->fs_devices && device->fs_devices->seeding) {
+                printk(KERN_INFO "btrfs: resizer unable to apply on "
+                       "seeding device %llu\n",
+                       (unsigned long long)devid);
+                ret = -EINVAL;
+                goto out_free;
+        }
+
         if (!strcmp(sizestr, "max"))
                 new_size = device->bdev->bd_inode->i_size;
         else {
@@ -1344,8 +1355,9 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
         do_div(new_size, root->sectorsize);
         new_size *= root->sectorsize;
 
-        printk(KERN_INFO "btrfs: new size for %s is %llu\n",
-                device->name, (unsigned long long)new_size);
+        printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
+                      rcu_str_deref(device->name),
+                      (unsigned long long)new_size);
 
         if (new_size > old_size) {
                 trans = btrfs_start_transaction(root, 0);
@@ -2262,10 +2274,17 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
         di_args->bytes_used = dev->bytes_used;
         di_args->total_bytes = dev->total_bytes;
         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
-        if (dev->name)
-                strncpy(di_args->path, dev->name, sizeof(di_args->path));
-        else
+        if (dev->name) {
+                struct rcu_string *name;
+
+                rcu_read_lock();
+                name = rcu_dereference(dev->name);
+                strncpy(di_args->path, name->str, sizeof(di_args->path));
+                rcu_read_unlock();
+                di_args->path[sizeof(di_args->path) - 1] = 0;
+        } else {
                 di_args->path[0] = '\0';
+        }
 
 out:
         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
@@ -2622,6 +2641,7 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
                         btrfs_mark_buffer_dirty(leaf);
                         btrfs_release_path(path);
 
+                        inode_inc_iversion(inode);
                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 
                         /*
@@ -2914,7 +2934,7 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
                 up_read(&info->groups_sem);
         }
 
-        user_dest = (struct btrfs_ioctl_space_info *)
+        user_dest = (struct btrfs_ioctl_space_info __user *)
                 (arg + sizeof(struct btrfs_ioctl_space_args));
 
         if (copy_to_user(user_dest, dest_orig, alloc_size))
@@ -3042,6 +3062,28 @@ static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
         return ret;
 }
 
+static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
+                                      void __user *arg, int reset_after_read)
+{
+        struct btrfs_ioctl_get_dev_stats *sa;
+        int ret;
+
+        if (reset_after_read && !capable(CAP_SYS_ADMIN))
+                return -EPERM;
+
+        sa = memdup_user(arg, sizeof(*sa));
+        if (IS_ERR(sa))
+                return PTR_ERR(sa);
+
+        ret = btrfs_get_dev_stats(root, sa, reset_after_read);
+
+        if (copy_to_user(arg, sa, sizeof(*sa)))
+                ret = -EFAULT;
+
+        kfree(sa);
+        return ret;
+}
+
 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
 {
         int ret = 0;
@@ -3212,8 +3254,9 @@ void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
         }
 }
 
-static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
+static long btrfs_ioctl_balance(struct file *file, void __user *arg)
 {
+        struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
         struct btrfs_fs_info *fs_info = root->fs_info;
         struct btrfs_ioctl_balance_args *bargs;
         struct btrfs_balance_control *bctl;
@@ -3225,6 +3268,10 @@ static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
         if (fs_info->sb->s_flags & MS_RDONLY)
                 return -EROFS;
 
+        ret = mnt_want_write(file->f_path.mnt);
+        if (ret)
+                return ret;
+
         mutex_lock(&fs_info->volume_mutex);
         mutex_lock(&fs_info->balance_mutex);
 
@@ -3291,6 +3338,7 @@ out_bargs:
 out:
         mutex_unlock(&fs_info->balance_mutex);
         mutex_unlock(&fs_info->volume_mutex);
+        mnt_drop_write(file->f_path.mnt);
         return ret;
 }
 
@@ -3386,7 +3434,7 @@ long btrfs_ioctl(struct file *file, unsigned int
         case BTRFS_IOC_DEV_INFO:
                 return btrfs_ioctl_dev_info(root, argp);
         case BTRFS_IOC_BALANCE:
-                return btrfs_ioctl_balance(root, NULL);
+                return btrfs_ioctl_balance(file, NULL);
         case BTRFS_IOC_CLONE:
                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
         case BTRFS_IOC_CLONE_RANGE:
@@ -3419,11 +3467,15 @@ long btrfs_ioctl(struct file *file, unsigned int
         case BTRFS_IOC_SCRUB_PROGRESS:
                 return btrfs_ioctl_scrub_progress(root, argp);
         case BTRFS_IOC_BALANCE_V2:
-                return btrfs_ioctl_balance(root, argp);
+                return btrfs_ioctl_balance(file, argp);
         case BTRFS_IOC_BALANCE_CTL:
                 return btrfs_ioctl_balance_ctl(root, arg);
         case BTRFS_IOC_BALANCE_PROGRESS:
                 return btrfs_ioctl_balance_progress(root, argp);
+        case BTRFS_IOC_GET_DEV_STATS:
+                return btrfs_ioctl_get_dev_stats(root, argp, 0);
+        case BTRFS_IOC_GET_AND_RESET_DEV_STATS:
+                return btrfs_ioctl_get_dev_stats(root, argp, 1);
         }
 
         return -ENOTTY;