diff options
author | Linus Torvalds | 2020-10-23 11:33:41 -0700 |
---|---|---|
committer | Linus Torvalds | 2020-10-23 11:33:41 -0700 |
commit | c4728cfbed0f54eacc21138c99da2a91895c8c5a (patch) | |
tree | 61e9ed33dd81da4e5ea9c485964ea9214a6c8b10 /mm/filemap.c | |
parent | f9a705ad1c077ec2872c641f0db9c0d5b4a097bb (diff) | |
parent | 407e9c63ee571f44a2dfb0828fc30daa02abb6dc (diff) |
Merge tag 'vfs-5.10-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull clone/dedupe/remap code refactoring from Darrick Wong:
"Move the generic file range remap (aka reflink and dedupe) functions
out of mm/filemap.c and fs/read_write.c and into fs/remap_range.c to
reduce clutter in the first two files"
* tag 'vfs-5.10-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: move the generic write and copy checks out of mm
vfs: move the remap range helpers to remap_range.c
vfs: move generic_remap_checks out of mm
Diffstat (limited to 'mm/filemap.c')
-rw-r--r-- | mm/filemap.c | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index e4101b5bfa82..d5e7c2029d16 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3121,228 +3121,6 @@ struct page *read_cache_page_gfp(struct address_space *mapping, } EXPORT_SYMBOL(read_cache_page_gfp); -/* - * Don't operate on ranges the page cache doesn't support, and don't exceed the - * LFS limits. If pos is under the limit it becomes a short access. If it - * exceeds the limit we return -EFBIG. - */ -static int generic_write_check_limits(struct file *file, loff_t pos, - loff_t *count) -{ - struct inode *inode = file->f_mapping->host; - loff_t max_size = inode->i_sb->s_maxbytes; - loff_t limit = rlimit(RLIMIT_FSIZE); - - if (limit != RLIM_INFINITY) { - if (pos >= limit) { - send_sig(SIGXFSZ, current, 0); - return -EFBIG; - } - *count = min(*count, limit - pos); - } - - if (!(file->f_flags & O_LARGEFILE)) - max_size = MAX_NON_LFS; - - if (unlikely(pos >= max_size)) - return -EFBIG; - - *count = min(*count, max_size - pos); - - return 0; -} - -/* - * Performs necessary checks before doing a write - * - * Can adjust writing position or amount of bytes to write. - * Returns appropriate error code that caller should return or - * zero in case that write should be allowed. - */ -inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) -{ - struct file *file = iocb->ki_filp; - struct inode *inode = file->f_mapping->host; - loff_t count; - int ret; - - if (IS_SWAPFILE(inode)) - return -ETXTBSY; - - if (!iov_iter_count(from)) - return 0; - - /* FIXME: this is for backwards compatibility with 2.4 */ - if (iocb->ki_flags & IOCB_APPEND) - iocb->ki_pos = i_size_read(inode); - - if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) - return -EINVAL; - - count = iov_iter_count(from); - ret = generic_write_check_limits(file, iocb->ki_pos, &count); - if (ret) - return ret; - - iov_iter_truncate(from, count); - return iov_iter_count(from); -} -EXPORT_SYMBOL(generic_write_checks); - -/* - * Performs necessary checks before doing a clone. - * - * Can adjust amount of bytes to clone via @req_count argument. - * Returns appropriate error code that caller should return or - * zero in case the clone should be allowed. - */ -int generic_remap_checks(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - loff_t *req_count, unsigned int remap_flags) -{ - struct inode *inode_in = file_in->f_mapping->host; - struct inode *inode_out = file_out->f_mapping->host; - uint64_t count = *req_count; - uint64_t bcount; - loff_t size_in, size_out; - loff_t bs = inode_out->i_sb->s_blocksize; - int ret; - - /* The start of both ranges must be aligned to an fs block. */ - if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs)) - return -EINVAL; - - /* Ensure offsets don't wrap. */ - if (pos_in + count < pos_in || pos_out + count < pos_out) - return -EINVAL; - - size_in = i_size_read(inode_in); - size_out = i_size_read(inode_out); - - /* Dedupe requires both ranges to be within EOF. */ - if ((remap_flags & REMAP_FILE_DEDUP) && - (pos_in >= size_in || pos_in + count > size_in || - pos_out >= size_out || pos_out + count > size_out)) - return -EINVAL; - - /* Ensure the infile range is within the infile. */ - if (pos_in >= size_in) - return -EINVAL; - count = min(count, size_in - (uint64_t)pos_in); - - ret = generic_write_check_limits(file_out, pos_out, &count); - if (ret) - return ret; - - /* - * If the user wanted us to link to the infile's EOF, round up to the - * next block boundary for this check. - * - * Otherwise, make sure the count is also block-aligned, having - * already confirmed the starting offsets' block alignment. - */ - if (pos_in + count == size_in) { - bcount = ALIGN(size_in, bs) - pos_in; - } else { - if (!IS_ALIGNED(count, bs)) - count = ALIGN_DOWN(count, bs); - bcount = count; - } - - /* Don't allow overlapped cloning within the same file. */ - if (inode_in == inode_out && - pos_out + bcount > pos_in && - pos_out < pos_in + bcount) - return -EINVAL; - - /* - * We shortened the request but the caller can't deal with that, so - * bounce the request back to userspace. - */ - if (*req_count != count && !(remap_flags & REMAP_FILE_CAN_SHORTEN)) - return -EINVAL; - - *req_count = count; - return 0; -} - - -/* - * Performs common checks before doing a file copy/clone - * from @file_in to @file_out. - */ -int generic_file_rw_checks(struct file *file_in, struct file *file_out) -{ - struct inode *inode_in = file_inode(file_in); - struct inode *inode_out = file_inode(file_out); - - /* Don't copy dirs, pipes, sockets... */ - if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) - return -EISDIR; - if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) - return -EINVAL; - - if (!(file_in->f_mode & FMODE_READ) || - !(file_out->f_mode & FMODE_WRITE) || - (file_out->f_flags & O_APPEND)) - return -EBADF; - - return 0; -} - -/* - * Performs necessary checks before doing a file copy - * - * Can adjust amount of bytes to copy via @req_count argument. - * Returns appropriate error code that caller should return or - * zero in case the copy should be allowed. - */ -int generic_copy_file_checks(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t *req_count, unsigned int flags) -{ - struct inode *inode_in = file_inode(file_in); - struct inode *inode_out = file_inode(file_out); - uint64_t count = *req_count; - loff_t size_in; - int ret; - - ret = generic_file_rw_checks(file_in, file_out); - if (ret) - return ret; - - /* Don't touch certain kinds of inodes */ - if (IS_IMMUTABLE(inode_out)) - return -EPERM; - - if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out)) - return -ETXTBSY; - - /* Ensure offsets don't wrap. */ - if (pos_in + count < pos_in || pos_out + count < pos_out) - return -EOVERFLOW; - - /* Shorten the copy to EOF */ - size_in = i_size_read(inode_in); - if (pos_in >= size_in) - count = 0; - else - count = min(count, size_in - (uint64_t)pos_in); - - ret = generic_write_check_limits(file_out, pos_out, &count); - if (ret) - return ret; - - /* Don't allow overlapped copying within the same file. */ - if (inode_in == inode_out && - pos_out + count > pos_in && - pos_out < pos_in + count) - return -EINVAL; - - *req_count = count; - return 0; -} - int pagecache_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) |