From 22fe404218156328a27e66349b1175cd0baa4990 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 18 Sep 2009 13:05:44 -0700 Subject: vfs: split generic_forget_inode() so that hugetlbfs does not have to copy it Hugetlbfs needs to do special things instead of truncate_inode_pages(). Currently, it copied generic_forget_inode() except for truncate_inode_pages() call which is asking for trouble (the code there isn't trivial). So create a separate function generic_detach_inode() which does all the list magic done in generic_forget_inode() and call it from hugetlbfs_forget_inode(). Signed-off-by: Jan Kara Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 51803528b09..955e34615cb 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2156,6 +2156,7 @@ extern ino_t iunique(struct super_block *, ino_t); extern int inode_needs_sync(struct inode *inode); extern void generic_delete_inode(struct inode *inode); extern void generic_drop_inode(struct inode *inode); +extern int generic_detach_inode(struct inode *inode); extern struct inode *ilookup5_nowait(struct super_block *sb, unsigned long hashval, int (*test)(struct inode *, void *), -- cgit v1.2.3 From 42cb56ae2ab67390da34906b27bedc3f2ff1393b Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 18 Sep 2009 13:05:53 -0700 Subject: vfs: change sb->s_maxbytes to a loff_t sb->s_maxbytes is supposed to indicate the maximum size of a file that can exist on the filesystem. It's declared as an unsigned long long. Even if a filesystem has no inherent limit that prevents it from using every bit in that unsigned long long, it's still problematic to set it to anything larger than MAX_LFS_FILESIZE. There are places in the kernel that cast s_maxbytes to a signed value. If it's set too large then this cast makes it a negative number and generally breaks the comparison. Change s_maxbytes to be loff_t instead. That should help eliminate the temptation to set it too large by making it a signed value. Also, add a warning for couple of releases to help catch filesystems that set s_maxbytes too large. Eventually we can either convert this to a BUG() or just remove it and in the hope that no one will get it wrong now that it's a signed value. Signed-off-by: Jeff Layton Cc: Johannes Weiner Cc: Christoph Hellwig Cc: Al Viro Cc: Robert Love Cc: Mandeep Singh Baines Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- include/linux/fs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 955e34615cb..cbb7724c11d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1315,7 +1315,7 @@ struct super_block { unsigned long s_blocksize; unsigned char s_blocksize_bits; unsigned char s_dirt; - unsigned long long s_maxbytes; /* Max file size */ + loff_t s_maxbytes; /* Max file size */ struct file_system_type *s_type; const struct super_operations *s_op; const struct dquot_operations *dq_op; -- cgit v1.2.3 From f84398068d9c2babe41500504ef247ae07081857 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Mon, 21 Sep 2009 14:48:36 +0200 Subject: vfs: seq_file: add helpers for data filling Add two helpers that allow access to the seq_file's own buffer, but hide the internal details of seq_files. This allows easier implementation of special purpose filling functions. It also cleans up some existing functions which duplicated the seq_file logic. Make these inline functions in seq_file.h, as suggested by Al. Signed-off-by: Miklos Szeredi Acked-by: Hugh Dickins Signed-off-by: Al Viro --- include/linux/seq_file.h | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) (limited to 'include') diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h index 0c6a86b7959..8366d8f12e5 100644 --- a/include/linux/seq_file.h +++ b/include/linux/seq_file.h @@ -35,6 +35,44 @@ struct seq_operations { #define SEQ_SKIP 1 +/** + * seq_get_buf - get buffer to write arbitrary data to + * @m: the seq_file handle + * @bufp: the beginning of the buffer is stored here + * + * Return the number of bytes available in the buffer, or zero if + * there's no space. + */ +static inline size_t seq_get_buf(struct seq_file *m, char **bufp) +{ + BUG_ON(m->count > m->size); + if (m->count < m->size) + *bufp = m->buf + m->count; + else + *bufp = NULL; + + return m->size - m->count; +} + +/** + * seq_commit - commit data to the buffer + * @m: the seq_file handle + * @num: the number of bytes to commit + * + * Commit @num bytes of data written to a buffer previously acquired + * by seq_buf_get. To signal an error condition, or that the data + * didn't fit in the available space, pass a negative @num value. + */ +static inline void seq_commit(struct seq_file *m, int num) +{ + if (num < 0) { + m->count = m->size; + } else { + BUG_ON(m->count + num > m->size); + m->count += num; + } +} + char *mangle_path(char *s, char *p, char *esc); int seq_open(struct file *, const struct seq_operations *); ssize_t seq_read(struct file *, char __user *, size_t, loff_t *); -- cgit v1.2.3 From 4fadd7bb20a1e7c774ed88dc703d8fbcd00ff917 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 3 Aug 2009 23:28:06 +0200 Subject: freeze_bdev: kill bd_mount_sem Now that we have the freeze count there is not much reason for bd_mount_sem anymore. The actual freeze/thaw operations are serialized using the bd_fsfreeze_mutex, and the only other place we take bd_mount_sem is get_sb_bdev which tries to prevent mounting a filesystem while the block device is frozen. Instead of add a check for bd_fsfreeze_count and return -EBUSY if a filesystem is frozen. While that is a change in user visible behaviour a failing mount is much better for this case rather than having the mount process stuck uninterruptible for a long time. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/fs.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index cbb7724c11d..72dfbd42397 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -640,7 +640,6 @@ struct block_device { struct super_block * bd_super; int bd_openers; struct mutex bd_mutex; /* open/close mutex */ - struct semaphore bd_mount_sem; struct list_head bd_inodes; void * bd_holder; int bd_holders; -- cgit v1.2.3 From 4504230a71566785a05d3e6b53fa1ee071b864eb Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 3 Aug 2009 23:28:35 +0200 Subject: freeze_bdev: grab active reference to frozen superblocks Currently we held s_umount while a filesystem is frozen, despite that we might return to userspace and unlock it from a different process. Instead grab an active reference to keep the file system busy and add an explicit check for frozen filesystems in remount and reject the remount instead of blocking on s_umount. Add a new get_active_super helper to super.c for use by freeze_bdev that grabs an active reference to a superblock from a given block device. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 72dfbd42397..502d96ef345 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2334,6 +2334,7 @@ extern void get_filesystem(struct file_system_type *fs); extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); extern struct super_block *get_super(struct block_device *); +extern struct super_block *get_active_super(struct block_device *bdev); extern struct super_block *user_get_super(dev_t); extern void drop_super(struct super_block *sb); -- cgit v1.2.3 From 25d9e2d15286281ec834b829a4aaf8969011f1cd Mon Sep 17 00:00:00 2001 From: "npiggin@suse.de" Date: Fri, 21 Aug 2009 02:35:05 +1000 Subject: truncate: new helpers Introduce new truncate helpers truncate_pagecache and inode_newsize_ok. vmtruncate is also consolidated from mm/memory.c and mm/nommu.c and into mm/truncate.c. Reviewed-by: Christoph Hellwig Signed-off-by: Nick Piggin Signed-off-by: Al Viro --- include/linux/fs.h | 3 ++- include/linux/mm.h | 5 +++-- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 502d96ef345..2b08b5ce09b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2382,7 +2382,8 @@ extern int buffer_migrate_page(struct address_space *, #define buffer_migrate_page NULL #endif -extern int inode_change_ok(struct inode *, struct iattr *); +extern int inode_change_ok(const struct inode *, struct iattr *); +extern int inode_newsize_ok(const struct inode *, loff_t offset); extern int __must_check inode_setattr(struct inode *, struct iattr *); extern void file_update_time(struct file *file); diff --git a/include/linux/mm.h b/include/linux/mm.h index b6eae5e3144..8347e938fb2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -791,8 +791,9 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping, unmap_mapping_range(mapping, holebegin, holelen, 0); } -extern int vmtruncate(struct inode * inode, loff_t offset); -extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end); +extern void truncate_pagecache(struct inode *inode, loff_t old, loff_t new); +extern int vmtruncate(struct inode *inode, loff_t offset); +extern int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end); #ifdef CONFIG_MMU extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, -- cgit v1.2.3