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2011-02-01btrfs: fix return value check of btrfs_start_transaction()Tsutomu Itoh7-6/+37
The error check of btrfs_start_transaction() is added, and the mistake of the error check on several places is corrected. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-01btrfs: checking NULL or not in some functionsTsutomu Itoh3-0/+10
Because NULL is returned when the memory allocation fails, it is checked whether it is NULL. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-31Btrfs: avoid uninit variable warnings in ordered-data.cChris Mason1-1/+1
This one isn't really an uninit variable, but for pretty obscure reasons. Let's make it clearly correct. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-31Btrfs: catch errors from btrfs_sync_logChris Mason1-1/+2
btrfs_sync_log returns -EAGAIN when we need full transaction commits instead of small log commits, but sometimes we were dropping the return value. In practice, we check for this a few different ways, but this is still a bug that can leave off full log commits when we really need them. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-31Btrfs: make shrink_delalloc a little friendlierJosef Bacik1-3/+14
Xfstests 224 will just sit there and spin for ever until eventually we give up flushing delalloc and exit. On my box this took several hours. I could not interrupt this process either, even though we use INTERRUPTIBLE. So do 2 things 1) Keep us from looping over and over again without reclaiming anything 2) If we get interrupted exit the loop I tested this and the test now exits in a reasonable amount of time, and can be interrupted with ctrl+c. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Btrfs: handle no memory properly in prepare_pagesJosef Bacik1-2/+6
Instead of doing a BUG_ON(1) in prepare_pages if grab_cache_page() fails, just loop through the pages we've already grabbed and unlock and release them, then return -ENOMEM like we should. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Btrfs: do error checking in btrfs_del_csumsJosef Bacik1-0/+3
Got a report of a box panicing because we got a NULL eb in read_extent_buffer. His fs was borked and btrfs_search_path returned EIO, but we don't check for errors so the box paniced. Yes I know this will just make something higher up the stack panic, but that's a problem for future Josef. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Btrfs: use the global block reserve if we cannot reserve spaceJosef Bacik1-1/+27
We call use_block_rsv right before we make an allocation in order to make sure we have enough space. Now normally people have called btrfs_start_transaction() with the appropriate amount of space that we need, so we just use some of that pre-reserved space and move along happily. The problem is where people use btrfs_join_transaction(), which doesn't actually reserve any space. So we try and reserve space here, but we cannot flush delalloc, so this forces us to return -ENOSPC when in reality we have plenty of space. The most common symptom is seeing a bunch of "couldn't dirty inode" messages in syslog. With xfstests 224 we end up falling back to start_transaction and then doing all the flush delalloc stuff which causes to hang for a very long time. So instead steal from the global reserve, which is what this is meant for anyway. With this patch and the other 2 I have sent xfstests 224 now passes successfully. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Btrfs: do not release more reserved bytes to the global_block_rsv than we needJosef Bacik1-2/+14
When we do btrfs_block_rsv_release, if global_block_rsv is not full we will release all the extra bytes to global_block_rsv, even if it's only a little short of the amount of space that we need to reserve. This causes us to starve ourselves of reservable space during the transaction which will force us to shrink delalloc bytes and commit the transaction more often than we should. So instead just add the amount of bytes we need to add to the global reserve so reserved == size, and then add the rest back into the space_info for general use. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Btrfs: fix check_path_shared so it returns the right valueJosef Bacik1-2/+3
When running xfstests 224 I kept getting ENOSPC when trying to remove the files, and this is because we were returning ret from check_path_shared while it was uninitalized, which isn't right. Fix this to return 0 properly, and now xfstests 224 doesn't freak out when it tries to clean itself up. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28btrfs: check return value of btrfs_start_ioctl_transaction() properlyTsutomu Itoh1-1/+1
btrfs_start_ioctl_transaction() returns ERR_PTR(), not NULL. So, it is necessary to use IS_ERR() to check the return value. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28btrfs: fix return value check of btrfs_join_transaction()Tsutomu Itoh6-13/+51
The error check of btrfs_join_transaction()/btrfs_join_transaction_nolock() is added, and the mistake of the error check in several places is corrected. For more stable Btrfs, I think that we should reduce BUG_ON(). But, I think that long time is necessary for this. So, I propose this patch as a short-term solution. With this patch: - To more stable Btrfs, the part that should be corrected is clarified. - The panic isn't done by the NULL pointer reference etc. (even if BUG_ON() is increased temporarily) - The error code is returned in the place where the error can be easily returned. As a long-term plan: - BUG_ON() is reduced by using the forced-readonly framework, etc. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28fs/btrfs/inode.c: Add missing IS_ERR testJulia Lawall1-1/+1
After the conditional that precedes the following code, inode may be an ERR_PTR value. This can eg result from a memory allocation failure via the call to btrfs_iget, and thus does not imply that root is different than sub_root. Thus, an IS_ERR check is added to ensure that there is no dereference of inode in this case. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r@ identifier f; @@ f(...) { ... return ERR_PTR(...); } @@ identifier r.f, fld; expression x; statement S1,S2; @@ x = f(...) ... when != IS_ERR(x) ( if (IS_ERR(x) ||...) S1 else S2 | *x->fld ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28btrfs: fix missing break in switch phraseliubo1-0/+1
There is a missing break in switch, fix it. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28btrfs: fix several uncheck memory allocationsliubo4-0/+33
To make btrfs more stable, add several missing necessary memory allocation checks, and when no memory, return proper errno. We've checked that some of those -ENOMEM errors will be returned to userspace, and some will be catched by BUG_ON() in the upper callers, and none will be ignored silently. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28btrfs: fix uncheck memory allocation in btrfs_submit_compressed_readliubo2-4/+25
btrfs_submit_compressed_read() is lack of memory allocation checks and corresponding error route. After this fix, if it comes to "no memory" case, errno will be returned to userland step by step, and tell users this operation cannot go on. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-28Merge branch 'bug-fixes' of git://repo.or.cz/linux-btrfs-devel into btrfs-38Chris Mason6-65/+117
2011-01-27Btrfs: Fix file clone when source offset is not 0Li Zefan1-1/+4
Suppose: - the source extent is: [0, 100] - the src offset is 10 - the clone length is 90 - the dest offset is 0 This statement: new_key.offset = key.offset + destoff - off will produce such an extent for the dest file: [ino, BTRFS_EXTENT_DATA_KEY, -10] , which is obviously wrong. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27Btrfs: Fix memory leak in writepage fixup workMiao Xie1-0/+1
fixup, which is allocated when starting page write to fix up the extent without ORDERED bit set, should be freed after this work is done. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27Btrfs: Don't return acl info when mounting with noacl optionMiao Xie1-0/+6
Steps to reproduce: # mkfs.btrfs /dev/sda2 # mount /dev/sda2 /mnt # touch /mnt/file0 # setfacl -m 'u:root:x,g::x,o::x' /mnt/file0 # umount /mnt # mount /dev/sda2 -o noacl /mnt # getfacl /mnt/file0 ... user::rw- user:root:--x group::--x mask::--x other::--x The output should be: user::rw- group::--x other::--x Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27Btrfs: Free correct pointer after using strsepTero Roponen1-2/+3
We must save and free the original kstrdup()'ed pointer because strsep() modifies its first argument. Signed-off-by: Tero Roponen <tero.roponen@gmail.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27Btrfs: Fix memory leak on finding existing superIan Kent1-0/+2
We missed a memory deallocation in commit 450ba0ea. If an existing super block is found at mount and there is no error condition then the pre-allocated tree_root and fs_info are no not used and are not freeded. Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27Btrfs: Fix memory leak at umountLi Zefan1-0/+2
fs_info, which is allocated in open_ctree(), should be freed in close_ctree(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Check mergeable free space when removing a clusterLi Zefan1-6/+20
After returing extents from a cluster to the block group, some extents in the block group may be mergeable. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Add a helper try_merge_free_space()Li Zefan1-32/+43
When adding a new extent, we'll firstly see if we can merge this extent to the left or/and right extent. Extract this as a helper try_merge_free_space(). As a side effect, we fix a small bug that if the new extent has non-bitmap left entry but is unmergeble, we'll directly link the extent without trying to drop it into bitmap. This also prepares for the next patch. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Update stats when allocating from a clusterLi Zefan1-3/+14
When allocating extent entry from a cluster, we should update the free_space and free_extents fields of the block group. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Free fully occupied bitmap in clusterLi Zefan1-0/+2
If there's no more free space in a bitmap, we should free it. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Add helper function free_bitmap()Li Zefan1-21/+16
Remove some duplicated code. This prepares for the next patch. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-27btrfs: Fix threshold calculation for block groups smaller than 1GBLi Zefan1-2/+6
If a block group is smaller than 1GB, the extent entry threadhold calculation will always set the threshold to 0. So as free space gets fragmented, btrfs will switch to use bitmap to manage free space, but then will never switch back to extents due to this bug. Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-01-17Btrfs: forced readonly mounts on errorsliubo7-2/+523
This patch comes from "Forced readonly mounts on errors" ideas. As we know, this is the first step in being more fault tolerant of disk corruptions instead of just using BUG() statements. The major content: - add a framework for generating errors that should result in filesystems going readonly. - keep FS state in disk super block. - make sure that all of resource will be freed and released at umount time. - make sure that fter FS is forced readonly on error, there will be no more disk change before FS is corrected. For this, we should stop write operation. After this patch is applied, the conversion from BUG() to such a framework can happen incrementally. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: Require CAP_SYS_ADMIN for filesystem rebalanceBen Hutchings1-0/+4
Filesystem rebalancing (BTRFS_IOC_BALANCE) affects the entire filesystem and may run uninterruptibly for a long time. This does not seem to be something that an unprivileged user should be able to do. Reported-by: Aron Xu <happyaron.xu@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16Btrfs: don't warn if we get ENOSPC in btrfs_block_rsv_checkJosef Bacik1-5/+0
If we run low on space we could get a bunch of warnings out of btrfs_block_rsv_check, but this is mostly just called via the transaction code to see if we need to end the transaction, it expects to see failures, so let's not WARN and freak everybody out for no reason. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: Fix memory leak in btrfs_read_fs_root_no_radix()Tsutomu Itoh1-0/+1
In btrfs_read_fs_root_no_radix(), 'root' is not freed if btrfs_search_slot() returns error. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: check NULL or notTsutomu Itoh3-0/+16
Should check if functions returns NULL or not. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: Don't pass NULL ptr to func that may deref it.Jesper Juhl1-0/+2
Hi, In fs/btrfs/inode.c::fixup_tree_root_location() we have this code: ... if (!path) { err = -ENOMEM; goto out; } ... out: btrfs_free_path(path); return err; btrfs_free_path() passes its argument on to other functions and some of them end up dereferencing the pointer. In the code above that pointer is clearly NULL, so btrfs_free_path() will eventually cause a NULL dereference. There are many ways to cut this cake (fix the bug). The one I chose was to make btrfs_free_path() deal gracefully with NULL pointers. If you disagree, feel free to come up with an alternative patch. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: mount failure return value fixDave Young2-4/+8
I happened to pass swap partition as root partition in cmdline, then kernel panic and tell me about "Cannot open root device". It is not correct, in fact it is a fs type mismatch instead of 'no device'. Eventually I found btrfs mounting failed with -EIO, it should be -EINVAL. The logic in init/do_mounts.c: for (p = fs_names; *p; p += strlen(p)+1) { int err = do_mount_root(name, p, flags, root_mount_data); switch (err) { case 0: goto out; case -EACCES: flags |= MS_RDONLY; goto retry; case -EINVAL: continue; } print "Cannot open root device" panic } SO fs type after btrfs will have no chance to mount Here fix the return value as -EINVAL Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: Mem leak in btrfs_get_acl()Jesper Juhl1-1/+3
It seems to me that we leak the memory allocated to 'value' in btrfs_get_acl() if the call to posix_acl_from_xattr() fails. Here's a patch that attempts to correct that problem. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: fix wrong free space information of btrfsMiao Xie5-7/+286
When we store data by raid profile in btrfs with two or more different size disks, df command shows there is some free space in the filesystem, but the user can not write any data in fact, df command shows the wrong free space information of btrfs. # mkfs.btrfs -d raid1 /dev/sda9 /dev/sda10 # btrfs-show Label: none uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64 Total devices 2 FS bytes used 28.00KB devid 1 size 5.01GB used 2.03GB path /dev/sda9 devid 2 size 10.00GB used 2.01GB path /dev/sda10 # btrfs device scan /dev/sda9 /dev/sda10 # mount /dev/sda9 /mnt # dd if=/dev/zero of=tmpfile0 bs=4K count=9999999999 (fill the filesystem) # sync # df -TH Filesystem Type Size Used Avail Use% Mounted on /dev/sda9 btrfs 17G 8.6G 5.4G 62% /mnt # btrfs-show Label: none uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64 Total devices 2 FS bytes used 3.99GB devid 1 size 5.01GB used 5.01GB path /dev/sda9 devid 2 size 10.00GB used 4.99GB path /dev/sda10 It is because btrfs cannot allocate chunks when one of the pairing disks has no space, the free space on the other disks can not be used for ever, and should be subtracted from the total space, but btrfs doesn't subtract this space from the total. It is strange to the user. This patch fixes it by calcing the free space that can be used to allocate chunks. Implementation: 1. get all the devices free space, and align them by stripe length. 2. sort the devices by the free space. 3. check the free space of the devices, 3.1. if it is not zero, and then check the number of the devices that has more free space than this device, if the number of the devices is beyond the min stripe number, the free space can be used, and add into total free space. if the number of the devices is below the min stripe number, we can not use the free space, the check ends. 3.2. if the free space is zero, check the next devices, goto 3.1 This implementation is just likely fake chunk allocation. After appling this patch, df can show correct space information: # df -TH Filesystem Type Size Used Avail Use% Mounted on /dev/sda9 btrfs 17G 8.6G 0 100% /mnt Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: make the chunk allocator utilize the devices betterMiao Xie2-103/+300
With this patch, we change the handling method when we can not get enough free extents with default size. Implementation: 1. Look up the suitable free extent on each device and keep the search result. If not find a suitable free extent, keep the max free extent 2. If we get enough suitable free extents with default size, chunk allocation succeeds. 3. If we can not get enough free extents, but the number of the extent with default size is >= min_stripes, we just change the mapping information (reduce the number of stripes in the extent map), and chunk allocation succeeds. 4. If the number of the extent with default size is < min_stripes, sort the devices by its max free extent's size descending 5. Use the size of the max free extent on the (num_stripes - 1)th device as the stripe size to allocate the device space By this way, the chunk allocator can allocate chunks as large as possible when the devices' space is not enough and make full use of the devices. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: restructure find_free_dev_extent()Miao Xie2-68/+91
- make it return the start position and length of the max free space when it can not find a suitable free space. - make it more readability Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: fix wrong calculation of stripe sizeMiao Xie1-2/+8
There are two tiny problem: - One is When we check the chunk size is greater than the max chunk size or not, we should take mirrors into account, but the original code didn't. - The other is btrfs shouldn't use the size of the residual free space as the length of of a dup chunk when doing chunk allocation. It is because the device space that a dup chunk needs is twice as large as the chunk size, if we use the size of the residual free space as the length of a dup chunk, we can not get enough free space. Fix it. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: try to reclaim some space when chunk allocation failsMiao Xie1-2/+7
We cannot write data into files when when there is tiny space in the filesystem. Reproduce steps: # mkfs.btrfs /dev/sda1 # mount /dev/sda1 /mnt # dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1 # dd if=/dev/zero of=/mnt/tmpfile1 bs=4K count=99999999999999 (fill the filesystem) # umount /mnt # mount /dev/sda1 /mnt # rm -f /mnt/tmpfile0 # dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1 (failed with nospec) But if we do the last step again, we can write data successfully. The reason of the problem is that btrfs didn't try to commit the current transaction and reclaim some space when chunk allocation failed. This patch fixes it by committing the current transaction to reclaim some space when chunk allocation fails. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16btrfs: fix wrong data space statisticsMiao Xie1-4/+3
Josef has implemented mixed data/metadata chunks, we must add those chunks' space just like data chunks. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16fs/btrfs: Fix build of ctreeStefan Schmidt1-0/+1
CC [M] fs/btrfs/ctree.o In file included from fs/btrfs/ctree.c:21:0: fs/btrfs/ctree.h:1003:17: error: field <91>super_kobj<92> has incomplete type fs/btrfs/ctree.h:1074:17: error: field <91>root_kobj<92> has incomplete type make[2]: *** [fs/btrfs/ctree.o] Error 1 make[1]: *** [fs/btrfs] Error 2 make: *** [fs] Error 2 We need to include kobject.h here. Reported-by: Jeff Garzik <jeff@garzik.org> Fix-suggested-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16Merge branch 'lzo-support' of git://repo.or.cz/linux-btrfs-devel into btrfs-38Chris Mason20-385/+1051
2011-01-16Merge branch 'readonly-snapshots' of git://repo.or.cz/linux-btrfs-devel into ↵Chris Mason7-49/+195
btrfs-38
2011-01-04Btrfs: fix off by one while setting block groups readonlyChris Mason1-1/+2
When we read in block groups, we'll set non-redundant groups readonly if we find a raid1, DUP or raid10 group. But the ro code has an off by one bug in the math around testing to make sure out accounting doesn't go wrong. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-23Btrfs: Add BTRFS_IOC_SUBVOL_GETFLAGS/SETFLAGS ioctlsLi Zefan2-0/+85
This allows us to set a snapshot or a subvolume readonly or writable on the fly. Usage: Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and then call ioctl(BTRFS_IOCTL_SUBVOL_SETFLAGS); Changelog for v3: - Change to pass __u64 as ioctl parameter. Changelog for v2: - Add _GETFLAGS ioctl. - Check if the passed fd is the root of a subvolume. - Change the name from _SNAP_SETFLAGS to _SUBVOL_SETFLAGS. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-23Btrfs: Add readonly snapshots supportLi Zefan7-10/+75
Usage: Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and call ioctl(BTRFS_I0CTL_SNAP_CREATE_V2). Implementation: - Set readonly bit of btrfs_root_item->flags. - Add readonly checks in btrfs_permission (inode_permission), btrfs_setattr, btrfs_set/remove_xattr and some ioctls. Changelog for v3: - Eliminate btrfs_root->readonly, but check btrfs_root->root_item.flags. - Rename BTRFS_ROOT_SNAP_RDONLY to BTRFS_ROOT_SUBVOL_RDONLY. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-23Btrfs: Refactor btrfs_ioctl_snap_create()Li Zefan1-44/+40
Split it into two functions for two different ioctls, since they share no common code. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>