diff options
Diffstat (limited to 'mm/filemap.c')
-rw-r--r-- | mm/filemap.c | 101 |
1 files changed, 18 insertions, 83 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 47263ac..c11418d 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -28,6 +28,7 @@ #include <linux/blkdev.h> #include <linux/security.h> #include <linux/syscalls.h> +#include "filemap.h" /* * FIXME: remove all knowledge of the buffer layer from the core VM */ @@ -1004,7 +1005,7 @@ __generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov, if (pos < size) { retval = generic_file_direct_IO(READ, iocb, iov, pos, nr_segs); - if (retval >= 0 && !is_sync_kiocb(iocb)) + if (retval > 0 && !is_sync_kiocb(iocb)) retval = -EIOCBQUEUED; if (retval > 0) *ppos = pos + retval; @@ -1714,32 +1715,7 @@ int remove_suid(struct dentry *dentry) } EXPORT_SYMBOL(remove_suid); -/* - * Copy as much as we can into the page and return the number of bytes which - * were sucessfully copied. If a fault is encountered then clear the page - * out to (offset+bytes) and return the number of bytes which were copied. - */ -static inline size_t -filemap_copy_from_user(struct page *page, unsigned long offset, - const char __user *buf, unsigned bytes) -{ - char *kaddr; - int left; - - kaddr = kmap_atomic(page, KM_USER0); - left = __copy_from_user_inatomic(kaddr + offset, buf, bytes); - kunmap_atomic(kaddr, KM_USER0); - - if (left != 0) { - /* Do it the slow way */ - kaddr = kmap(page); - left = __copy_from_user(kaddr + offset, buf, bytes); - kunmap(page); - } - return bytes - left; -} - -static size_t +size_t __filemap_copy_from_user_iovec(char *vaddr, const struct iovec *iov, size_t base, size_t bytes) { @@ -1767,52 +1743,6 @@ __filemap_copy_from_user_iovec(char *vaddr, } /* - * This has the same sideeffects and return value as filemap_copy_from_user(). - * The difference is that on a fault we need to memset the remainder of the - * page (out to offset+bytes), to emulate filemap_copy_from_user()'s - * single-segment behaviour. - */ -static inline size_t -filemap_copy_from_user_iovec(struct page *page, unsigned long offset, - const struct iovec *iov, size_t base, size_t bytes) -{ - char *kaddr; - size_t copied; - - kaddr = kmap_atomic(page, KM_USER0); - copied = __filemap_copy_from_user_iovec(kaddr + offset, iov, - base, bytes); - kunmap_atomic(kaddr, KM_USER0); - if (copied != bytes) { - kaddr = kmap(page); - copied = __filemap_copy_from_user_iovec(kaddr + offset, iov, - base, bytes); - kunmap(page); - } - return copied; -} - -static inline void -filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) -{ - const struct iovec *iov = *iovp; - size_t base = *basep; - - while (bytes) { - int copy = min(bytes, iov->iov_len - base); - - bytes -= copy; - base += copy; - if (iov->iov_len == base) { - iov++; - base = 0; - } - } - *iovp = iov; - *basep = base; -} - -/* * Performs necessary checks before doing a write * * Can adjust writing position aor amount of bytes to write. @@ -1827,12 +1757,6 @@ inline int generic_write_checks(struct file *file, loff_t *pos, size_t *count, i if (unlikely(*pos < 0)) return -EINVAL; - if (unlikely(file->f_error)) { - int err = file->f_error; - file->f_error = 0; - return err; - } - if (!isblk) { /* FIXME: this is for backwards compatibility with 2.4 */ if (file->f_flags & O_APPEND) @@ -1927,8 +1851,11 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov, * i_sem is held, which protects generic_osync_inode() from * livelocking. */ - if (written >= 0 && file->f_flags & O_SYNC) - generic_osync_inode(inode, mapping, OSYNC_METADATA); + if (written >= 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { + int err = generic_osync_inode(inode, mapping, OSYNC_METADATA); + if (err < 0) + written = err; + } if (written == count && !is_sync_kiocb(iocb)) written = -EIOCBQUEUED; return written; @@ -1968,6 +1895,7 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, do { unsigned long index; unsigned long offset; + unsigned long maxlen; size_t copied; offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */ @@ -1982,7 +1910,10 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, * same page as we're writing to, without it being marked * up-to-date. */ - fault_in_pages_readable(buf, bytes); + maxlen = cur_iov->iov_len - iov_base; + if (maxlen > bytes) + maxlen = bytes; + fault_in_pages_readable(buf, maxlen); page = __grab_cache_page(mapping,index,&cached_page,&lru_pvec); if (!page) { @@ -2023,7 +1954,11 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, if (unlikely(nr_segs > 1)) { filemap_set_next_iovec(&cur_iov, &iov_base, status); - buf = cur_iov->iov_base + iov_base; + if (count) + buf = cur_iov->iov_base + + iov_base; + } else { + iov_base += status; } } } |