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author | Boaz Harrosh <bharrosh@panasas.com> | 2010-01-28 12:58:08 +0300 |
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committer | Boaz Harrosh <bharrosh@panasas.com> | 2010-02-28 14:35:28 +0300 |
commit | d9c740d2253e75db8cef8f87a3125c450f3ebd82 (patch) | |
tree | 7217cf62b8d102e00257be6e0675d25852045bc6 /fs/exofs/inode.c | |
parent | 46f4d973f6874c06b7a41a3bf8f4c1717d90f97a (diff) | |
download | linux-d9c740d2253e75db8cef8f87a3125c450f3ebd82.tar.xz |
exofs: Define on-disk per-inode optional layout attribute
* Layouts describe the way a file is spread on multiple devices.
The layout information is stored in the objects attribute introduced
in this patch.
* There can be multiple generating function for the layout.
Currently defined:
- No attribute present - use below moving-window on global
device table, all devices.
(This is the only one currently used in exofs)
- an obj_id generated moving window - the obj_id is a randomizing
factor in the otherwise global map layout.
- An explicit layout stored, including a data_map and a device
index list.
- More might be defined in future ...
* There are two attributes defined of the same structure:
A-data-files-layout - This layout is used by data-files. If present
at a directory, all files of that directory will
be created with this layout.
A-meta-data-layout - This layout is used by a directory and other
meta-data information. Also inherited at creation
of subdirectories.
* At creation time inodes are created with the layout specified above.
A usermode utility may change the creation layout on a give directory
or file. Which in the case of directories, will also apply to newly
created files/subdirectories, children of that directory.
In the simple unaltered case of a newly created exofs, no layout
attributes are present, and all layouts adhere to the layout specified
at the device-table.
* In case of a future file system loaded in an old exofs-driver.
At iget(), the generating_function is inspected and if not supported
will return an IO error to the application and the inode will not
be loaded. So not to damage any data.
Note: After this patch we do not yet support any type of layout
only the RAID0 patch that enables striping at the super-block
level will add support for RAID0 layouts above. This way we
are past and future compatible and fully bisectable.
* Access to the device table is done by an accessor since
it will change according to above information.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Diffstat (limited to 'fs/exofs/inode.c')
-rw-r--r-- | fs/exofs/inode.c | 56 |
1 files changed, 51 insertions, 5 deletions
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c index 03189a958b33..0163546ba05a 100644 --- a/fs/exofs/inode.c +++ b/fs/exofs/inode.c @@ -859,6 +859,15 @@ int exofs_setattr(struct dentry *dentry, struct iattr *iattr) return error; } +static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF( + EXOFS_APAGE_FS_DATA, + EXOFS_ATTR_INODE_FILE_LAYOUT, + 0); +static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF( + EXOFS_APAGE_FS_DATA, + EXOFS_ATTR_INODE_DIR_LAYOUT, + 0); + /* * Read an inode from the OSD, and return it as is. We also return the size * attribute in the 'obj_size' argument. @@ -867,11 +876,16 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi, struct exofs_fcb *inode, uint64_t *obj_size) { struct exofs_sb_info *sbi = sb->s_fs_info; - struct osd_attr attrs[2]; + struct osd_attr attrs[] = { + [0] = g_attr_inode_data, + [1] = g_attr_inode_file_layout, + [2] = g_attr_inode_dir_layout, + [3] = g_attr_logical_length, + }; struct exofs_io_state *ios; + struct exofs_on_disk_inode_layout *layout; int ret; - *obj_size = ~0; ret = exofs_get_io_state(&sbi->layout, &ios); if (unlikely(ret)) { EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__); @@ -882,8 +896,9 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi, exofs_make_credential(oi->i_cred, &ios->obj); ios->cred = oi->i_cred; - attrs[0] = g_attr_inode_data; - attrs[1] = g_attr_logical_length; + attrs[1].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs); + attrs[2].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs); + ios->in_attr = attrs; ios->in_attr_len = ARRAY_SIZE(attrs); @@ -901,11 +916,42 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi, ret = extract_attr_from_ios(ios, &attrs[1]); if (ret) { + EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__); + goto out; + } + if (attrs[1].len) { + layout = attrs[1].val_ptr; + if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) { + EXOFS_ERR("%s: unsupported files layout %d\n", + __func__, layout->gen_func); + ret = -ENOTSUPP; + goto out; + } + } + + ret = extract_attr_from_ios(ios, &attrs[2]); + if (ret) { + EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__); + goto out; + } + if (attrs[2].len) { + layout = attrs[2].val_ptr; + if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) { + EXOFS_ERR("%s: unsupported meta-data layout %d\n", + __func__, layout->gen_func); + ret = -ENOTSUPP; + goto out; + } + } + + *obj_size = ~0; + ret = extract_attr_from_ios(ios, &attrs[3]); + if (ret) { EXOFS_ERR("%s: extract_attr of logical_length failed\n", __func__); goto out; } - *obj_size = get_unaligned_be64(attrs[1].val_ptr); + *obj_size = get_unaligned_be64(attrs[3].val_ptr); out: exofs_put_io_state(ios); |