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path: root/fs/internal.h
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2019-04-09unexport d_alloc_pseudo()Al Viro
No modular uses since introducion of alloc_file_pseudo(), and the only non-modular user not in alloc_file_pseudo() had actually been wrong - should've been d_alloc_anon(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-04acct_on(): don't mess with freeze protectionAl Viro
What happens there is that we are replacing file->path.mnt of a file we'd just opened with a clone and we need the write count contribution to be transferred from original mount to new one. That's it. We do *NOT* want any kind of freeze protection for the duration of switchover. IOW, we should just use __mnt_{want,drop}_write() for that switchover; no need to bother with mnt_{want,drop}_write() there. Tested-by: Amir Goldstein <amir73il@gmail.com> Reported-by: syzbot+2a73a6ea9507b7112141@syzkaller.appspotmail.com Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-28vfs: Add configuration parser helpersDavid Howells
Because the new API passes in key,value parameters, match_token() cannot be used with it. Instead, provide three new helpers to aid with parsing: (1) fs_parse(). This takes a parameter and a simple static description of all the parameters and maps the key name to an ID. It returns 1 on a match, 0 on no match if unknowns should be ignored and some other negative error code on a parse error. The parameter description includes a list of key names to IDs, desired parameter types and a list of enumeration name -> ID mappings. [!] Note that for the moment I've required that the key->ID mapping array is expected to be sorted and unterminated. The size of the array is noted in the fsconfig_parser struct. This allows me to use bsearch(), but I'm not sure any performance gain is worth the hassle of requiring people to keep the array sorted. The parameter type array is sized according to the number of parameter IDs and is indexed directly. The optional enum mapping array is an unterminated, unsorted list and the size goes into the fsconfig_parser struct. The function can do some additional things: (a) If it's not ambiguous and no value is given, the prefix "no" on a key name is permitted to indicate that the parameter should be considered negatory. (b) If the desired type is a single simple integer, it will perform an appropriate conversion and store the result in a union in the parse result. (c) If the desired type is an enumeration, {key ID, name} will be looked up in the enumeration list and the matching value will be stored in the parse result union. (d) Optionally generate an error if the key is unrecognised. This is called something like: enum rdt_param { Opt_cdp, Opt_cdpl2, Opt_mba_mpbs, nr__rdt_params }; const struct fs_parameter_spec rdt_param_specs[nr__rdt_params] = { [Opt_cdp] = { fs_param_is_bool }, [Opt_cdpl2] = { fs_param_is_bool }, [Opt_mba_mpbs] = { fs_param_is_bool }, }; const const char *const rdt_param_keys[nr__rdt_params] = { [Opt_cdp] = "cdp", [Opt_cdpl2] = "cdpl2", [Opt_mba_mpbs] = "mba_mbps", }; const struct fs_parameter_description rdt_parser = { .name = "rdt", .nr_params = nr__rdt_params, .keys = rdt_param_keys, .specs = rdt_param_specs, .no_source = true, }; int rdt_parse_param(struct fs_context *fc, struct fs_parameter *param) { struct fs_parse_result parse; struct rdt_fs_context *ctx = rdt_fc2context(fc); int ret; ret = fs_parse(fc, &rdt_parser, param, &parse); if (ret < 0) return ret; switch (parse.key) { case Opt_cdp: ctx->enable_cdpl3 = true; return 0; case Opt_cdpl2: ctx->enable_cdpl2 = true; return 0; case Opt_mba_mpbs: ctx->enable_mba_mbps = true; return 0; } return -EINVAL; } (2) fs_lookup_param(). This takes a { dirfd, path, LOOKUP_EMPTY? } or string value and performs an appropriate path lookup to convert it into a path object, which it will then return. If the desired type was a blockdev, the type of the looked up inode will be checked to make sure it is one. This can be used like: enum foo_param { Opt_source, nr__foo_params }; const struct fs_parameter_spec foo_param_specs[nr__foo_params] = { [Opt_source] = { fs_param_is_blockdev }, }; const char *char foo_param_keys[nr__foo_params] = { [Opt_source] = "source", }; const struct constant_table foo_param_alt_keys[] = { { "device", Opt_source }, }; const struct fs_parameter_description foo_parser = { .name = "foo", .nr_params = nr__foo_params, .nr_alt_keys = ARRAY_SIZE(foo_param_alt_keys), .keys = foo_param_keys, .alt_keys = foo_param_alt_keys, .specs = foo_param_specs, }; int foo_parse_param(struct fs_context *fc, struct fs_parameter *param) { struct fs_parse_result parse; struct foo_fs_context *ctx = foo_fc2context(fc); int ret; ret = fs_parse(fc, &foo_parser, param, &parse); if (ret < 0) return ret; switch (parse.key) { case Opt_source: return fs_lookup_param(fc, &foo_parser, param, &parse, &ctx->source); default: return -EINVAL; } } (3) lookup_constant(). This takes a table of named constants and looks up the given name within it. The table is expected to be sorted such that bsearch() be used upon it. Possibly I should require the table be terminated and just use a for-loop to scan it instead of using bsearch() to reduce hassle. Tables look something like: static const struct constant_table bool_names[] = { { "0", false }, { "1", true }, { "false", false }, { "no", false }, { "true", true }, { "yes", true }, }; and a lookup is done with something like: b = lookup_constant(bool_names, param->string, -1); Additionally, optional validation routines for the parameter description are provided that can be enabled at compile time. A later patch will invoke these when a filesystem is registered. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-01-30introduce fs_context methodsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-01-30convert do_remount_sb() to fs_contextDavid Howells
Replace do_remount_sb() with a function, reconfigure_super(), that's fs_context aware. The fs_context is expected to be parameterised already and have ->root pointing to the superblock to be reconfigured. A legacy wrapper is provided that is intended to be called from the fs_context ops when those appear, but for now is called directly from reconfigure_super(). This wrapper invokes the ->remount_fs() superblock op for the moment. It is intended that the remount_fs() op will be phased out. The fs_context->purpose is set to FS_CONTEXT_FOR_RECONFIGURE to indicate that the context is being used for reconfiguration. do_umount_root() is provided to consolidate remount-to-R/O for umount and emergency remount by creating a context and invoking reconfiguration. do_remount(), do_umount() and do_emergency_remount_callback() are switched to use the new process. [AV -- fold UMOUNT and EMERGENCY_REMOUNT in; fixes the umount / bug, gets rid of pointless complexity] [AV -- set ->net_ns in all cases; nfs remount will need that] [AV -- shift security_sb_remount() call into reconfigure_super(); the callers that didn't do security_sb_remount() have NULL fc->security anyway, so it's a no-op for them] Signed-off-by: David Howells <dhowells@redhat.com> Co-developed-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-01-30vfs_get_tree(): evict the call of security_sb_kern_mount()Al Viro
Right now vfs_get_tree() calls security_sb_kern_mount() (i.e. mount MAC) unless it gets MS_KERNMOUNT or MS_SUBMOUNT in flags. Doing it that way is both clumsy and imprecise. Consider the callers' tree of vfs_get_tree(): vfs_get_tree() <- do_new_mount() <- vfs_kern_mount() <- simple_pin_fs() <- vfs_submount() <- kern_mount_data() <- init_mount_tree() <- btrfs_mount() <- vfs_get_tree() <- nfs_do_root_mount() <- nfs4_try_mount() <- nfs_fs_mount() <- vfs_get_tree() <- nfs4_referral_mount() do_new_mount() always does need MAC (we are guaranteed that neither MS_KERNMOUNT nor MS_SUBMOUNT will be passed there). simple_pin_fs(), vfs_submount() and kern_mount_data() pass explicit flags inhibiting that check. So does nfs4_referral_mount() (the flags there are ulimately coming from vfs_submount()). init_mount_tree() is called too early for anything LSM-related; it doesn't matter whether we attempt those checks, they'll do nothing. Finally, in case of btrfs_mount() and nfs_fs_mount(), doing MAC is pointless - either the caller will do it, or the flags are such that we wouldn't have done it either. In other words, the one and only case when we want that check done is when we are called from do_new_mount(), and there we want it unconditionally. So let's simply move it there. The superblock is still locked, so nobody is going to get access to it (via ustat(2), etc.) until we get a chance to apply the checks - we are free to move them to any point up to where we drop ->s_umount (in do_new_mount_fc()). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-01-30vfs: Introduce fs_context, switch vfs_kern_mount() to it.David Howells
Introduce a filesystem context concept to be used during superblock creation for mount and superblock reconfiguration for remount. This is allocated at the beginning of the mount procedure and into it is placed: (1) Filesystem type. (2) Namespaces. (3) Source/Device names (there may be multiple). (4) Superblock flags (SB_*). (5) Security details. (6) Filesystem-specific data, as set by the mount options. Accessor functions are then provided to set up a context, parameterise it from monolithic mount data (the data page passed to mount(2)) and tear it down again. A legacy wrapper is provided that implements what will be the basic operations, wrapping access to filesystems that aren't yet aware of the fs_context. Finally, vfs_kern_mount() is changed to make use of the fs_context and mount_fs() is replaced by vfs_get_tree(), called from vfs_kern_mount(). [AV -- add missing kstrdup()] [AV -- put_cred() can be unconditional - fc->cred can't be NULL] [AV -- take legacy_validate() contents into legacy_parse_monolithic()] [AV -- merge KERNEL_MOUNT and USER_MOUNT] [AV -- don't unlock superblock on success return from vfs_get_tree()] [AV -- kill 'reference' argument of init_fs_context()] Signed-off-by: David Howells <dhowells@redhat.com> Co-developed-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-21Merge tag 'ovl-update-4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "This contains two new features: - Stack file operations: this allows removal of several hacks from the VFS, proper interaction of read-only open files with copy-up, possibility to implement fs modifying ioctls properly, and others. - Metadata only copy-up: when file is on lower layer and only metadata is modified (except size) then only copy up the metadata and continue to use the data from the lower file" * tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (66 commits) ovl: Enable metadata only feature ovl: Do not do metacopy only for ioctl modifying file attr ovl: Do not do metadata only copy-up for truncate operation ovl: add helper to force data copy-up ovl: Check redirect on index as well ovl: Set redirect on upper inode when it is linked ovl: Set redirect on metacopy files upon rename ovl: Do not set dentry type ORIGIN for broken hardlinks ovl: Add an inode flag OVL_CONST_INO ovl: Treat metacopy dentries as type OVL_PATH_MERGE ovl: Check redirects for metacopy files ovl: Move some dir related ovl_lookup_single() code in else block ovl: Do not expose metacopy only dentry from d_real() ovl: Open file with data except for the case of fsync ovl: Add helper ovl_inode_realdata() ovl: Store lower data inode in ovl_inode ovl: Fix ovl_getattr() to get number of blocks from lower ovl: Add helper ovl_dentry_lowerdata() to get lower data dentry ovl: Copy up meta inode data from lowest data inode ovl: Modify ovl_lookup() and friends to lookup metacopy dentry ...
2018-08-13Merge branch 'iomap-4.19-merge' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull fs iomap refactoring from Darrick Wong: "This is the first part of the XFS changes for 4.19. Christoph and Andreas coordinated some refactoring work on the iomap code in preparation for removing buffer heads from XFS and porting gfs2 to iomap. I'm sending this small pull request ahead of the main XFS merge to avoid holding up gfs2 unnecessarily" * 'iomap-4.19-merge' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: iomap: add inline data support to iomap_readpage_actor iomap: support direct I/O to inline data iomap: refactor iomap_dio_actor iomap: add initial support for writes without buffer heads iomap: add an iomap-based readpage and readpages implementation iomap: add private pointer to struct iomap iomap: add a page_done callback iomap: generic inline data handling iomap: complete partial direct I/O writes synchronously iomap: mark newly allocated buffer heads as new fs: factor out a __generic_write_end helper
2018-07-18Revert "vfs: update ovl inode before relatime check"Miklos Szeredi
This reverts commit 598e3c8f72f5b77c84d2cb26cfd936ffb3cfdbaa. Overlayfs no longer relies on the vfs correct atime handling. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-18Revert "ovl: don't allow writing ioctl on lower layer"Miklos Szeredi
This reverts commit 7c6893e3c9abf6a9676e060a1e35e5caca673d57. Overlayfs no longer relies on the vfs for checking writability of files. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-18vfs: export vfs_ioctl() to modulesMiklos Szeredi
This is needed by the stacked ioctl implementation in overlayfs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-18vfs: make open_with_fake_path() not contribute to nr_filesMiklos Szeredi
Stacking file operations in overlay will store an extra open file for each overlay file opened. The overhead is just that of "struct file" which is about 256bytes, because overlay already pins an extra dentry and inode when the file is open, which add up to a much larger overhead. For fear of breaking working setups, don't start accounting the extra file. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-12now we can fold open_check_o_direct() into do_dentry_open()Al Viro
These checks are better off in do_dentry_open(); the reason we couldn't put them there used to be that callers couldn't tell what kind of cleanup would do_dentry_open() failure call for. Now that we have FMODE_OPENED, cleanup is the same in all cases - it's simply fput(). So let's fold that into do_dentry_open(), as Christoph's patch tried to. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12get rid of cred argument of vfs_open() and do_dentry_open()Al Viro
always equal to ->f_cred Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12pass ->f_flags value to alloc_empty_file()Al Viro
... and have it set the f_flags-derived part of ->f_mode. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12pass creds to get_empty_filp(), make sure dentry_open() passes the right credsAl Viro
... and rename get_empty_filp() to alloc_empty_file(). dentry_open() gets creds as argument, but the only thing that sees those is security_file_open() - file->f_cred still ends up with current_cred(). For almost all callers it's the same thing, but there are several broken cases. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-10drm_mode_create_lease_ioctl(): fix open-coded filp_clone_open()Al Viro
Failure of ->open() should *not* be followed by fput(). Fixed by using filp_clone_open(), which gets the cleanups right. Cc: stable@vger.kernel.org Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-06-19fs: factor out a __generic_write_end helperChristoph Hellwig
Bits of the buffer.c based write_end implementations that don't know about buffer_heads and can be reused by other implementations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-03Revert "fs: fold open_check_o_direct into do_dentry_open"Al Viro
This reverts commit cab64df194667dc5d9d786f0a895f647f5501c0d. Having vfs_open() in some cases drop the reference to struct file combined with error = vfs_open(path, f, cred); if (error) { put_filp(f); return ERR_PTR(error); } return f; is flat-out wrong. It used to be error = vfs_open(path, f, cred); if (!error) { /* from now on we need fput() to dispose of f */ error = open_check_o_direct(f); if (error) { fput(f); f = ERR_PTR(error); } } else { put_filp(f); f = ERR_PTR(error); } and sure, having that open_check_o_direct() boilerplate gotten rid of is nice, but not that way... Worse, another call chain (via finish_open()) is FUBAR now wrt FILE_OPENED handling - in that case we get error returned, with file already hit by fput() *AND* FILE_OPENED not set. Guess what happens in path_openat(), when it hits if (!(opened & FILE_OPENED)) { BUG_ON(!error); put_filp(file); } The root cause of all that crap is that the callers of do_dentry_open() have no way to tell which way did it fail; while that could be fixed up (by passing something like int *opened to do_dentry_open() and have it marked if we'd called ->open()), it's probably much too late in the cycle to do so right now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-06Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted stuff, including Christoph's I_DIRTY patches" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: move I_DIRTY_INODE to fs.h ubifs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call ntfs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call gfs2: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) calls fs: fold open_check_o_direct into do_dentry_open vfs: Replace stray non-ASCII homoglyph characters with their ASCII equivalents vfs: make sure struct filename->iname is word-aligned get rid of pointless includes of fs_struct.h [poll] annotate SAA6588_CMD_POLL users
2018-04-02fs: add ksys_ftruncate() wrapper; remove in-kernel calls to sys_ftruncate()Dominik Brodowski
Using the ksys_ftruncate() wrapper allows us to get rid of in-kernel calls to the sys_ftruncate() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_ftruncate(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_fchownat(), ksys_fchown() helpers and ksys_{,l}chown() wrappersDominik Brodowski
Using the fs-interal do_fchownat() wrapper allows us to get rid of fs-internal calls to the sys_fchownat() syscall. Introducing the ksys_fchown() helper and the ksys_{,}chown() wrappers allows us to avoid the in-kernel calls to the sys_{,l,f}chown() syscalls. The ksys_ prefix denotes that these functions are meant as a drop-in replacement for the syscalls. In particular, they use the same calling convention as sys_{,l,f}chown(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_faccessat() helper and ksys_access() wrapper; remove in-kernel ↵Dominik Brodowski
calls to syscall Using the fs-internal do_faccessat() helper allows us to get rid of fs-internal calls to the sys_faccessat() syscall. Introducing the ksys_access() wrapper allows us to avoid the in-kernel calls to the sys_access() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_access(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add ksys_fchmod() and do_fchmodat() helpers and ksys_chmod() wrapper; ↵Dominik Brodowski
remove in-kernel calls to syscall Using the fs-internal do_fchmodat() helper allows us to get rid of fs-internal calls to the sys_fchmodat() syscall. Introducing the ksys_fchmod() helper and the ksys_chmod() wrapper allows us to avoid the in-kernel calls to the sys_fchmod() and sys_chmod() syscalls. The ksys_ prefix denotes that these functions are meant as a drop-in replacement for the syscalls. In particular, they use the same calling convention as sys_fchmod() and sys_chmod(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_linkat() helper and ksys_link() wrapper; remove in-kernel calls ↵Dominik Brodowski
to syscall Using the fs-internal do_linkat() helper allows us to get rid of fs-internal calls to the sys_linkat() syscall. Introducing the ksys_link() wrapper allows us to avoid the in-kernel calls to sys_link() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_link(). In the near future, the only fs-external user of ksys_link() should be converted to use vfs_link() instead. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_mknodat() helper and ksys_mknod() wrapper; remove in-kernel calls ↵Dominik Brodowski
to syscall Using the fs-internal do_mknodat() helper allows us to get rid of fs-internal calls to the sys_mknodat() syscall. Introducing the ksys_mknod() wrapper allows us to avoid the in-kernel calls to sys_mknod() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mknod(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_symlinkat() helper and ksys_symlink() wrapper; remove in-kernel ↵Dominik Brodowski
calls to syscall Using the fs-internal do_symlinkat() helper allows us to get rid of fs-internal calls to the sys_symlinkat() syscall. Introducing the ksys_symlink() wrapper allows us to avoid the in-kernel calls to the sys_symlink() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_symlink(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add do_mkdirat() helper and ksys_mkdir() wrapper; remove in-kernel calls ↵Dominik Brodowski
to syscall Using the fs-internal do_mkdirat() helper allows us to get rid of fs-internal calls to the sys_mkdirat() syscall. Introducing the ksys_mkdir() wrapper allows us to avoid the in-kernel calls to the sys_mkdir() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mkdir(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02fs: add ksys_rmdir() wrapper; remove in-kernel calls to sys_rmdir()Dominik Brodowski
Using this wrapper allows us to avoid the in-kernel calls to the sys_rmdir() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_rmdir(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-03-28fs: fold open_check_o_direct into do_dentry_openChristoph Hellwig
do_dentry_open is where we do the actual open of the file, so this is where we should do our O_DIRECT sanity check to cover all potential callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-10fs: expose do_unlinkat for built-in callersChristoph Hellwig
And make it take a struct filename instead of a user pointer. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-13Merge branch 'overlayfs-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "This fixes d_ino correctness in readdir, which brings overlayfs on par with normal filesystems regarding inode number semantics, as long as all layers are on the same filesystem. There are also some bug fixes, one in particular (random ioctl's shouldn't be able to modify lower layers) that touches some vfs code, but of course no-op for non-overlay fs" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: fix false positive ESTALE on lookup ovl: don't allow writing ioctl on lower layer ovl: fix relatime for directories vfs: add flags to d_real() ovl: cleanup d_real for negative ovl: constant d_ino for non-merge dirs ovl: constant d_ino across copy up ovl: fix readdir error value ovl: check snprintf return
2017-09-05ovl: don't allow writing ioctl on lower layerMiklos Szeredi
Problem with ioctl() is that it's a file operation, yet often used as an inode operation (i.e. modify the inode despite the file being opened for read-only). mnt_want_write_file() is used by filesystems in such cases to get write access on an arbitrary open file. Since overlayfs lets filesystems do all file operations, including ioctl, this can lead to mnt_want_write_file() returning OK for a lower file and modification of that lower file. This patch prevents modification by checking if the file is from an overlayfs lower layer and returning EPERM in that case. Need to introduce a mnt_want_write_file_path() variant that still does the old thing for inode operations that can do the copy up + modification correctly in such cases (fchown, fsetxattr, fremovexattr). This does not address the correctness of such ioctls on overlayfs (the correct way would be to copy up and attempt to perform ioctl on upper file). In theory this could be a regression. We very much hope that nobody is relying on such a hack in any sane setup. While this patch meddles in VFS code, it has no effect on non-overlayfs filesystems. Reported-by: "zhangyi (F)" <yi.zhang@huawei.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-09-01xfs: evict all inodes involved with log redo itemDarrick J. Wong
When we introduced the bmap redo log items, we set MS_ACTIVE on the mountpoint and XFS_IRECOVERY on the inode to prevent unlinked inodes from being truncated prematurely during log recovery. This also had the effect of putting linked inodes on the lru instead of evicting them. Unfortunately, we neglected to find all those unreferenced lru inodes and evict them after finishing log recovery, which means that we leak them if anything goes wrong in the rest of xfs_mountfs, because the lru is only cleaned out on unmount. Therefore, evict unreferenced inodes in the lru list immediately after clearing MS_ACTIVE. Fixes: 17c12bcd30 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Cc: viro@ZenIV.linux.org.uk Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-05-09Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted bits and pieces from various people. No common topic in this pile, sorry" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs/affs: add rename exchange fs/affs: add rename2 to prepare multiple methods Make stat/lstat/fstatat pass AT_NO_AUTOMOUNT to vfs_statx() fs: don't set *REFERENCED on single use objects fs: compat: Remove warning from COMPATIBLE_IOCTL remove pointless extern of atime_need_update_rcu() fs: completely ignore unknown open flags fs: add a VALID_OPEN_FLAGS fs: remove _submit_bh() fs: constify tree_descr arrays passed to simple_fill_super() fs: drop duplicate header percpu-rwsem.h fs/affs: bugfix: Write files greater than page size on OFS fs/affs: bugfix: enable writes on OFS disks fs/affs: remove node generation check fs/affs: import amigaffs.h fs/affs: bugfix: make symbolic links work again
2017-04-29remove pointless extern of atime_need_update_rcu()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-17fhandle: move compat syscalls from compat.cAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-30iomap: constify struct iomap_opsChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2016-12-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: "In this pile: - autofs-namespace series - dedupe stuff - more struct path constification" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits) ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features ocfs2: charge quota for reflinked blocks ocfs2: fix bad pointer cast ocfs2: always unlock when completing dio writes ocfs2: don't eat io errors during _dio_end_io_write ocfs2: budget for extent tree splits when adding refcount flag ocfs2: prohibit refcounted swapfiles ocfs2: add newlines to some error messages ocfs2: convert inode refcount test to a helper simple_write_end(): don't zero in short copy into uptodate exofs: don't mess with simple_write_{begin,end} 9p: saner ->write_end() on failing copy into non-uptodate page fix gfs2_stuffed_write_end() on short copies fix ceph_write_end() nfs_write_end(): fix handling of short copies vfs: refactor clone/dedupe_file_range common functions fs: try to clone files first in vfs_copy_file_range vfs: misc struct path constification namespace.c: constify struct path passed to a bunch of primitives quota: constify struct path in quota_on ...
2016-12-05namespace.c: constify struct path passed to a bunch of primitivesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-11-30fs: make sb_init_dio_done_wq available outside of direct-io.cChristoph Hellwig
We want to use the per-sb completion workqueue from the new iomap direct I/O code. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Jens Axboe <axboe@fb.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-10-10Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted misc bits and pieces. There are several single-topic branches left after this (rename2 series from Miklos, current_time series from Deepa Dinamani, xattr series from Andreas, uaccess stuff from from me) and I'd prefer to send those separately" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits) proc: switch auxv to use of __mem_open() hpfs: support FIEMAP cifs: get rid of unused arguments of CIFSSMBWrite() posix_acl: uapi header split posix_acl: xattr representation cleanups fs/aio.c: eliminate redundant loads in put_aio_ring_file fs/internal.h: add const to ns_dentry_operations declaration compat: remove compat_printk() fs/buffer.c: make __getblk_slow() static proc: unsigned file descriptors fs/file: more unsigned file descriptors fs: compat: remove redundant check of nr_segs cachefiles: Fix attempt to read i_blocks after deleting file [ver #2] cifs: don't use memcpy() to copy struct iov_iter get rid of separate multipage fault-in primitives fs: Avoid premature clearing of capabilities fs: Give dentry to inode_change_ok() instead of inode fuse: Propagate dentry down to inode_change_ok() ceph: Propagate dentry down to inode_change_ok() xfs: Propagate dentry down to inode_change_ok() ...
2016-10-08Merge remote-tracking branch 'ovl/misc' into work.miscAl Viro
2016-09-27fs/internal.h: add const to ns_dentry_operations declarationRasmus Villemoes
The actual definition in fs/nsfs.c is already const. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-19iomap: expose iomap_apply outside iomap.cChristoph Hellwig
This allows the DAX code to use it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-09-16vfs: update ovl inode before relatime checkMiklos Szeredi
On overlayfs relatime_need_update() needs inode times to be correct on overlay inode. But i_mtime and i_ctime are updated by filesystem code on underlying inode only, so they will be out-of-date on the overlay inode. This patch copies the times from the underlying inode if needed. This can't be done if called from RCU lookup (link following) but link m/ctime are not updated by fs, so this is all right. This patch doesn't change functionality for anything but overlayfs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-08-07Merge tag 'binfmt-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/binfmt_misc Pull binfmt_misc update from James Bottomley: "This update is to allow architecture emulation containers to function such that the emulation binary can be housed outside the container itself. The container and fs parts both have acks from relevant experts. To use the new feature you have to add an F option to your binfmt_misc configuration" From the docs: "The usual behaviour of binfmt_misc is to spawn the binary lazily when the misc format file is invoked. However, this doesn't work very well in the face of mount namespaces and changeroots, so the F mode opens the binary as soon as the emulation is installed and uses the opened image to spawn the emulator, meaning it is always available once installed, regardless of how the environment changes" * tag 'binfmt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/binfmt_misc: binfmt_misc: add F option description to documentation binfmt_misc: add persistent opened binary handler for containers fs: add filp_clone_open API
2016-08-03Merge branch 'for-viro' of ↵Al Viro
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into for-linus
2016-08-03vfs: make dentry_needs_remove_privs() internalMiklos Szeredi
Only used by the vfs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>