1 files changed, 215 insertions, 53 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index b3bd912df6bf..d964195ea0e2 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -383,6 +383,21 @@ static int __check_block_validity(struct inode *inode, const char *func,
         return 0;
 }
 
+int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
+                       ext4_lblk_t len)
+{
+        int ret;
+
+        if (ext4_encrypted_inode(inode))
+                return ext4_encrypted_zeroout(inode, lblk, pblk, len);
+
+        ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
+        if (ret > 0)
+                ret = 0;
+
+        return ret;
+}
+
 #define check_block_validity(inode, map)        \
         __check_block_validity((inode), __func__, __LINE__, (map))
 
@@ -403,8 +418,7 @@ static void ext4_map_blocks_es_recheck(handle_t *handle,
          * out taking i_data_sem.  So at the time the unwritten extent
          * could be converted.
          */
-        if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
-                down_read(&EXT4_I(inode)->i_data_sem);
+        down_read(&EXT4_I(inode)->i_data_sem);
         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
                 retval = ext4_ext_map_blocks(handle, inode, map, flags &
                                              EXT4_GET_BLOCKS_KEEP_SIZE);
@@ -412,8 +426,7 @@ static void ext4_map_blocks_es_recheck(handle_t *handle,
                 retval = ext4_ind_map_blocks(handle, inode, map, flags &
                                              EXT4_GET_BLOCKS_KEEP_SIZE);
         }
-        if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
-                up_read((&EXT4_I(inode)->i_data_sem));
+        up_read((&EXT4_I(inode)->i_data_sem));
 
         /*
          * We don't check m_len because extent will be collpased in status
@@ -509,8 +522,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
          * Try to see if we can get the block without requesting a new
          * file system block.
          */
-        if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
-                down_read(&EXT4_I(inode)->i_data_sem);
+        down_read(&EXT4_I(inode)->i_data_sem);
         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
                 retval = ext4_ext_map_blocks(handle, inode, map, flags &
                                              EXT4_GET_BLOCKS_KEEP_SIZE);
@@ -541,8 +553,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
                 if (ret < 0)
                         retval = ret;
         }
-        if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
-                up_read((&EXT4_I(inode)->i_data_sem));
+        up_read((&EXT4_I(inode)->i_data_sem));
 
 found:
         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
@@ -626,13 +637,29 @@ found:
                 }
 
                 /*
+                 * We have to zeroout blocks before inserting them into extent
+                 * status tree. Otherwise someone could look them up there and
+                 * use them before they are really zeroed.
+                 */
+                if (flags & EXT4_GET_BLOCKS_ZERO &&
+                    map->m_flags & EXT4_MAP_MAPPED &&
+                    map->m_flags & EXT4_MAP_NEW) {
+                        ret = ext4_issue_zeroout(inode, map->m_lblk,
+                                                 map->m_pblk, map->m_len);
+                        if (ret) {
+                                retval = ret;
+                                goto out_sem;
+                        }
+                }
+
+                /*
                  * If the extent has been zeroed out, we don't need to update
                  * extent status tree.
                  */
                 if ((flags & EXT4_GET_BLOCKS_PRE_IO) &&
                     ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
                         if (ext4_es_is_written(&es))
-                                goto has_zeroout;
+                                goto out_sem;
                 }
                 status = map->m_flags & EXT4_MAP_UNWRITTEN ?
                                 EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
@@ -643,11 +670,13 @@ found:
                         status |= EXTENT_STATUS_DELAYED;
                 ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
                                             map->m_pblk, status);
-                if (ret < 0)
+                if (ret < 0) {
                         retval = ret;
+                        goto out_sem;
+                }
         }
 
-has_zeroout:
+out_sem:
         up_write((&EXT4_I(inode)->i_data_sem));
         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
                 ret = check_block_validity(inode, map);
@@ -674,7 +703,7 @@ static int _ext4_get_block(struct inode *inode, sector_t iblock,
         map.m_lblk = iblock;
         map.m_len = bh->b_size >> inode->i_blkbits;
 
-        if (flags && !(flags & EXT4_GET_BLOCKS_NO_LOCK) && !handle) {
+        if (flags && !handle) {
                 /* Direct IO write... */
                 if (map.m_len > DIO_MAX_BLOCKS)
                         map.m_len = DIO_MAX_BLOCKS;
@@ -694,16 +723,6 @@ static int _ext4_get_block(struct inode *inode, sector_t iblock,
 
                 map_bh(bh, inode->i_sb, map.m_pblk);
                 bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
-                if (IS_DAX(inode) && buffer_unwritten(bh)) {
-                        /*
-                         * dgc: I suspect unwritten conversion on ext4+DAX is
-                         * fundamentally broken here when there are concurrent
-                         * read/write in progress on this inode.
-                         */
-                        WARN_ON_ONCE(io_end);
-                        bh->b_assoc_map = inode->i_mapping;
-                        bh->b_private = (void *)(unsigned long)iblock;
-                }
                 if (io_end && io_end->flag & EXT4_IO_END_UNWRITTEN)
                         set_buffer_defer_completion(bh);
                 bh->b_size = inode->i_sb->s_blocksize * map.m_len;
@@ -879,9 +898,6 @@ int do_journal_get_write_access(handle_t *handle,
         return ret;
 }
 
-static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
-                   struct buffer_head *bh_result, int create);
-
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len,
                                   get_block_t *get_block)
@@ -3054,25 +3070,96 @@ int ext4_get_block_write(struct inode *inode, sector_t iblock,
                                EXT4_GET_BLOCKS_IO_CREATE_EXT);
 }
 
-static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
+static int ext4_get_block_overwrite(struct inode *inode, sector_t iblock,
                    struct buffer_head *bh_result, int create)
 {
-        ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
+        int ret;
+
+        ext4_debug("ext4_get_block_overwrite: inode %lu, create flag %d\n",
                    inode->i_ino, create);
-        return _ext4_get_block(inode, iblock, bh_result,
-                               EXT4_GET_BLOCKS_NO_LOCK);
+        ret = _ext4_get_block(inode, iblock, bh_result, 0);
+        /*
+         * Blocks should have been preallocated! ext4_file_write_iter() checks
+         * that.
+         */
+        WARN_ON_ONCE(!buffer_mapped(bh_result));
+
+        return ret;
 }
 
-int ext4_get_block_dax(struct inode *inode, sector_t iblock,
-                   struct buffer_head *bh_result, int create)
+#ifdef CONFIG_FS_DAX
+int ext4_dax_mmap_get_block(struct inode *inode, sector_t iblock,
+                            struct buffer_head *bh_result, int create)
 {
-        int flags = EXT4_GET_BLOCKS_PRE_IO | EXT4_GET_BLOCKS_UNWRIT_EXT;
-        if (create)
-                flags |= EXT4_GET_BLOCKS_CREATE;
-        ext4_debug("ext4_get_block_dax: inode %lu, create flag %d\n",
+        int ret, err;
+        int credits;
+        struct ext4_map_blocks map;
+        handle_t *handle = NULL;
+        int flags = 0;
+
+        ext4_debug("ext4_dax_mmap_get_block: inode %lu, create flag %d\n",
                    inode->i_ino, create);
-        return _ext4_get_block(inode, iblock, bh_result, flags);
+        map.m_lblk = iblock;
+        map.m_len = bh_result->b_size >> inode->i_blkbits;
+        credits = ext4_chunk_trans_blocks(inode, map.m_len);
+        if (create) {
+                flags |= EXT4_GET_BLOCKS_PRE_IO | EXT4_GET_BLOCKS_CREATE_ZERO;
+                handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
+                if (IS_ERR(handle)) {
+                        ret = PTR_ERR(handle);
+                        return ret;
+                }
+        }
+
+        ret = ext4_map_blocks(handle, inode, &map, flags);
+        if (create) {
+                err = ext4_journal_stop(handle);
+                if (ret >= 0 && err < 0)
+                        ret = err;
+        }
+        if (ret <= 0)
+                goto out;
+        if (map.m_flags & EXT4_MAP_UNWRITTEN) {
+                int err2;
+
+                /*
+                 * We are protected by i_mmap_sem so we know block cannot go
+                 * away from under us even though we dropped i_data_sem.
+                 * Convert extent to written and write zeros there.
+                 *
+                 * Note: We may get here even when create == 0.
+                 */
+                handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits);
+                if (IS_ERR(handle)) {
+                        ret = PTR_ERR(handle);
+                        goto out;
+                }
+
+                err = ext4_map_blocks(handle, inode, &map,
+                      EXT4_GET_BLOCKS_CONVERT | EXT4_GET_BLOCKS_CREATE_ZERO);
+                if (err < 0)
+                        ret = err;
+                err2 = ext4_journal_stop(handle);
+                if (err2 < 0 && ret > 0)
+                        ret = err2;
+        }
+out:
+        WARN_ON_ONCE(ret == 0 && create);
+        if (ret > 0) {
+                map_bh(bh_result, inode->i_sb, map.m_pblk);
+                bh_result->b_state = (bh_result->b_state & ~EXT4_MAP_FLAGS) |
+                                        map.m_flags;
+                /*
+                 * At least for now we have to clear BH_New so that DAX code
+                 * doesn't attempt to zero blocks again in a racy way.
+                 */
+                bh_result->b_state &= ~(1 << BH_New);
+                bh_result->b_size = map.m_len << inode->i_blkbits;
+                ret = 0;
+        }
+        return ret;
 }
+#endif
 
 static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
                             ssize_t size, void *private)
@@ -3143,10 +3230,8 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
         /* If we do a overwrite dio, i_mutex locking can be released */
         overwrite = *((int *)iocb->private);
 
-        if (overwrite) {
-                down_read(&EXT4_I(inode)->i_data_sem);
+        if (overwrite)
                 mutex_unlock(&inode->i_mutex);
-        }
 
         /*
          * We could direct write to holes and fallocate.
@@ -3189,7 +3274,7 @@ static ssize_t ext4_ext_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
         }
 
         if (overwrite) {
-                get_block_func = ext4_get_block_write_nolock;
+                get_block_func = ext4_get_block_overwrite;
         } else {
                 get_block_func = ext4_get_block_write;
                 dio_flags = DIO_LOCKING;
@@ -3245,10 +3330,8 @@ retake_lock:
         if (iov_iter_rw(iter) == WRITE)
                 inode_dio_end(inode);
         /* take i_mutex locking again if we do a ovewrite dio */
-        if (overwrite) {
-                up_read(&EXT4_I(inode)->i_data_sem);
+        if (overwrite)
                 mutex_lock(&inode->i_mutex);
-        }
 
         return ret;
 }
@@ -3559,6 +3642,35 @@ int ext4_can_truncate(struct inode *inode)
 }
 
 /*
+ * We have to make sure i_disksize gets properly updated before we truncate
+ * page cache due to hole punching or zero range. Otherwise i_disksize update
+ * can get lost as it may have been postponed to submission of writeback but
+ * that will never happen after we truncate page cache.
+ */
+int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
+                                      loff_t len)
+{
+        handle_t *handle;
+        loff_t size = i_size_read(inode);
+
+        WARN_ON(!mutex_is_locked(&inode->i_mutex));
+        if (offset > size || offset + len < size)
+                return 0;
+
+        if (EXT4_I(inode)->i_disksize >= size)
+                return 0;
+
+        handle = ext4_journal_start(inode, EXT4_HT_MISC, 1);
+        if (IS_ERR(handle))
+                return PTR_ERR(handle);
+        ext4_update_i_disksize(inode, size);
+        ext4_mark_inode_dirty(handle, inode);
+        ext4_journal_stop(handle);
+
+        return 0;
+}
+
+/*
  * ext4_punch_hole: punches a hole in a file by releaseing the blocks
  * associated with the given offset and length
  *
@@ -3623,17 +3735,26 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
 
         }
 
+        /* Wait all existing dio workers, newcomers will block on i_mutex */
+        ext4_inode_block_unlocked_dio(inode);
+        inode_dio_wait(inode);
+
+        /*
+         * Prevent page faults from reinstantiating pages we have released from
+         * page cache.
+         */
+        down_write(&EXT4_I(inode)->i_mmap_sem);
         first_block_offset = round_up(offset, sb->s_blocksize);
         last_block_offset = round_down((offset + length), sb->s_blocksize) - 1;
 
         /* Now release the pages and zero block aligned part of pages*/
-        if (last_block_offset > first_block_offset)
+        if (last_block_offset > first_block_offset) {
+                ret = ext4_update_disksize_before_punch(inode, offset, length);
+                if (ret)
+                        goto out_dio;
                 truncate_pagecache_range(inode, first_block_offset,
                                          last_block_offset);
-
-        /* Wait all existing dio workers, newcomers will block on i_mutex */
-        ext4_inode_block_unlocked_dio(inode);
-        inode_dio_wait(inode);
+        }
 
         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
                 credits = ext4_writepage_trans_blocks(inode);
@@ -3680,16 +3801,12 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
         if (IS_SYNC(inode))
                 ext4_handle_sync(handle);
 
-        /* Now release the pages again to reduce race window */
-        if (last_block_offset > first_block_offset)
-                truncate_pagecache_range(inode, first_block_offset,
-                                         last_block_offset);
-
         inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
         ext4_mark_inode_dirty(handle, inode);
 out_stop:
         ext4_journal_stop(handle);
 out_dio:
+        up_write(&EXT4_I(inode)->i_mmap_sem);
         ext4_inode_resume_unlocked_dio(inode);
 out_mutex:
         mutex_unlock(&inode->i_mutex);
@@ -4076,6 +4193,14 @@ static inline void ext4_iget_extra_inode(struct inode *inode,
                 EXT4_I(inode)->i_inline_off = 0;
 }
 
+int ext4_get_projid(struct inode *inode, kprojid_t *projid)
+{
+        if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, EXT4_FEATURE_RO_COMPAT_PROJECT))
+                return -EOPNOTSUPP;
+        *projid = EXT4_I(inode)->i_projid;
+        return 0;
+}
+
 struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
 {
         struct ext4_iloc iloc;
@@ -4087,6 +4212,7 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         int block;
         uid_t i_uid;
         gid_t i_gid;
+        projid_t i_projid;
 
         inode = iget_locked(sb, ino);
         if (!inode)
@@ -4136,12 +4262,20 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
         i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
         i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_PROJECT) &&
+            EXT4_INODE_SIZE(sb) > EXT4_GOOD_OLD_INODE_SIZE &&
+            EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
+                i_projid = (projid_t)le32_to_cpu(raw_inode->i_projid);
+        else
+                i_projid = EXT4_DEF_PROJID;
+
         if (!(test_opt(inode->i_sb, NO_UID32))) {
                 i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
                 i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
         }
         i_uid_write(inode, i_uid);
         i_gid_write(inode, i_gid);
+        ei->i_projid = make_kprojid(&init_user_ns, i_projid);
         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 
         ext4_clear_state_flags(ei);     /* Only relevant on 32-bit archs */
@@ -4440,6 +4574,7 @@ static int ext4_do_update_inode(handle_t *handle,
         int need_datasync = 0, set_large_file = 0;
         uid_t i_uid;
         gid_t i_gid;
+        projid_t i_projid;
 
         spin_lock(&ei->i_raw_lock);
 
@@ -4452,6 +4587,7 @@ static int ext4_do_update_inode(handle_t *handle,
         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
         i_uid = i_uid_read(inode);
         i_gid = i_gid_read(inode);
+        i_projid = from_kprojid(&init_user_ns, ei->i_projid);
         if (!(test_opt(inode->i_sb, NO_UID32))) {
                 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
                 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
@@ -4529,6 +4665,15 @@ static int ext4_do_update_inode(handle_t *handle,
                                 cpu_to_le16(ei->i_extra_isize);
                 }
         }
+
+        BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+                        EXT4_FEATURE_RO_COMPAT_PROJECT) &&
+               i_projid != EXT4_DEF_PROJID);
+
+        if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
+            EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
+                raw_inode->i_projid = cpu_to_le32(i_projid);
+
         ext4_inode_csum_set(inode, raw_inode, ei);
         spin_unlock(&ei->i_raw_lock);
         if (inode->i_sb->s_flags & MS_LAZYTIME)
@@ -4824,6 +4969,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
                         } else
                                 ext4_wait_for_tail_page_commit(inode);
                 }
+                down_write(&EXT4_I(inode)->i_mmap_sem);
                 /*
                  * Truncate pagecache after we've waited for commit
                  * in data=journal mode to make pages freeable.
@@ -4831,6 +4977,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
                 truncate_pagecache(inode, inode->i_size);
                 if (shrink)
                         ext4_truncate(inode);
+                up_write(&EXT4_I(inode)->i_mmap_sem);
         }
 
         if (!rc) {
@@ -5279,6 +5426,8 @@ int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 
         sb_start_pagefault(inode->i_sb);
         file_update_time(vma->vm_file);
+
+        down_read(&EXT4_I(inode)->i_mmap_sem);
         /* Delalloc case is easy... */
         if (test_opt(inode->i_sb, DELALLOC) &&
             !ext4_should_journal_data(inode) &&
@@ -5348,6 +5497,19 @@ retry_alloc:
 out_ret:
         ret = block_page_mkwrite_return(ret);
 out:
+        up_read(&EXT4_I(inode)->i_mmap_sem);
         sb_end_pagefault(inode->i_sb);
         return ret;
 }
+
+int ext4_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+        struct inode *inode = file_inode(vma->vm_file);
+        int err;
+
+        down_read(&EXT4_I(inode)->i_mmap_sem);
+        err = filemap_fault(vma, vmf);
+        up_read(&EXT4_I(inode)->i_mmap_sem);
+
+        return err;
+}