X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fshmem.c;h=51b3d6ccddab75ba33b7fded5ffaf75700770ccd;hb=c67de5b3c0bb48ac56f14928e11f1f7d76add26f;hp=7c455fbaff7b6a0ea9b98c66c89bbc59c8333a64;hpb=b00dc3ad74fdb676552d46ee573b88e927240d0c;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/shmem.c b/mm/shmem.c index 7c455fb..51b3d6c 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -23,11 +23,12 @@ * which makes it a completely usable filesystem. */ -#include #include #include -#include #include +#include +#include +#include #include #include #include @@ -46,6 +47,9 @@ #include #include #include +#include +#include + #include #include #include @@ -78,6 +82,7 @@ enum sgp_type { SGP_READ, /* don't exceed i_size, don't allocate page */ SGP_CACHE, /* don't exceed i_size, may allocate page */ SGP_WRITE, /* may exceed i_size, may allocate page */ + SGP_FAULT, /* same as SGP_CACHE, return with page locked */ }; static int shmem_getpage(struct inode *inode, unsigned long idx, @@ -89,8 +94,11 @@ static inline struct page *shmem_dir_alloc(gfp_t gfp_mask) * The above definition of ENTRIES_PER_PAGE, and the use of * BLOCKS_PER_PAGE on indirect pages, assume PAGE_CACHE_SIZE: * might be reconsidered if it ever diverges from PAGE_SIZE. + * + * Mobility flags are masked out as swap vectors cannot move */ - return alloc_pages(gfp_mask, PAGE_CACHE_SHIFT-PAGE_SHIFT); + return alloc_pages((gfp_mask & ~GFP_MOVABLE_MASK) | __GFP_ZERO, + PAGE_CACHE_SHIFT-PAGE_SHIFT); } static inline void shmem_dir_free(struct page *page) @@ -171,11 +179,12 @@ static inline void shmem_unacct_blocks(unsigned long flags, long pages) vm_unacct_memory(pages * VM_ACCT(PAGE_CACHE_SIZE)); } -static struct super_operations shmem_ops; -static struct address_space_operations shmem_aops; -static struct file_operations shmem_file_operations; -static struct inode_operations shmem_inode_operations; -static struct inode_operations shmem_dir_inode_operations; +static const struct super_operations shmem_ops; +static const struct address_space_operations shmem_aops; +static const struct file_operations shmem_file_operations; +static const struct inode_operations shmem_inode_operations; +static const struct inode_operations shmem_dir_inode_operations; +static const struct inode_operations shmem_special_inode_operations; static struct vm_operations_struct shmem_vm_ops; static struct backing_dev_info shmem_backing_dev_info __read_mostly = { @@ -367,7 +376,7 @@ static swp_entry_t *shmem_swp_alloc(struct shmem_inode_info *info, unsigned long } spin_unlock(&info->lock); - page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping) | __GFP_ZERO); + page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping)); if (page) set_page_private(page, 0); spin_lock(&info->lock); @@ -397,26 +406,38 @@ static swp_entry_t *shmem_swp_alloc(struct shmem_inode_info *info, unsigned long /* * shmem_free_swp - free some swap entries in a directory * - * @dir: pointer to the directory - * @edir: pointer after last entry of the directory + * @dir: pointer to the directory + * @edir: pointer after last entry of the directory + * @punch_lock: pointer to spinlock when needed for the holepunch case */ -static int shmem_free_swp(swp_entry_t *dir, swp_entry_t *edir) +static int shmem_free_swp(swp_entry_t *dir, swp_entry_t *edir, + spinlock_t *punch_lock) { + spinlock_t *punch_unlock = NULL; swp_entry_t *ptr; int freed = 0; for (ptr = dir; ptr < edir; ptr++) { if (ptr->val) { + if (unlikely(punch_lock)) { + punch_unlock = punch_lock; + punch_lock = NULL; + spin_lock(punch_unlock); + if (!ptr->val) + continue; + } free_swap_and_cache(*ptr); *ptr = (swp_entry_t){0}; freed++; } } + if (punch_unlock) + spin_unlock(punch_unlock); return freed; } -static int shmem_map_and_free_swp(struct page *subdir, - int offset, int limit, struct page ***dir) +static int shmem_map_and_free_swp(struct page *subdir, int offset, + int limit, struct page ***dir, spinlock_t *punch_lock) { swp_entry_t *ptr; int freed = 0; @@ -426,7 +447,8 @@ static int shmem_map_and_free_swp(struct page *subdir, int size = limit - offset; if (size > LATENCY_LIMIT) size = LATENCY_LIMIT; - freed += shmem_free_swp(ptr+offset, ptr+offset+size); + freed += shmem_free_swp(ptr+offset, ptr+offset+size, + punch_lock); if (need_resched()) { shmem_swp_unmap(ptr); if (*dir) { @@ -476,7 +498,10 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) long nr_swaps_freed = 0; int offset; int freed; - int punch_hole = 0; + int punch_hole; + spinlock_t *needs_lock; + spinlock_t *punch_lock; + unsigned long upper_limit; inode->i_ctime = inode->i_mtime = CURRENT_TIME; idx = (start + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; @@ -487,11 +512,20 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) info->flags |= SHMEM_TRUNCATE; if (likely(end == (loff_t) -1)) { limit = info->next_index; + upper_limit = SHMEM_MAX_INDEX; info->next_index = idx; + needs_lock = NULL; + punch_hole = 0; } else { - limit = (end + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - if (limit > info->next_index) - limit = info->next_index; + if (end + 1 >= inode->i_size) { /* we may free a little more */ + limit = (inode->i_size + PAGE_CACHE_SIZE - 1) >> + PAGE_CACHE_SHIFT; + upper_limit = SHMEM_MAX_INDEX; + } else { + limit = (end + 1) >> PAGE_CACHE_SHIFT; + upper_limit = limit; + } + needs_lock = &info->lock; punch_hole = 1; } @@ -508,12 +542,30 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) size = limit; if (size > SHMEM_NR_DIRECT) size = SHMEM_NR_DIRECT; - nr_swaps_freed = shmem_free_swp(ptr+idx, ptr+size); + nr_swaps_freed = shmem_free_swp(ptr+idx, ptr+size, needs_lock); } - if (!topdir) + + /* + * If there are no indirect blocks or we are punching a hole + * below indirect blocks, nothing to be done. + */ + if (!topdir || limit <= SHMEM_NR_DIRECT) goto done2; - BUG_ON(limit <= SHMEM_NR_DIRECT); + /* + * The truncation case has already dropped info->lock, and we're safe + * because i_size and next_index have already been lowered, preventing + * access beyond. But in the punch_hole case, we still need to take + * the lock when updating the swap directory, because there might be + * racing accesses by shmem_getpage(SGP_CACHE), shmem_unuse_inode or + * shmem_writepage. However, whenever we find we can remove a whole + * directory page (not at the misaligned start or end of the range), + * we first NULLify its pointer in the level above, and then have no + * need to take the lock when updating its contents: needs_lock and + * punch_lock (either pointing to info->lock or NULL) manage this. + */ + + upper_limit -= SHMEM_NR_DIRECT; limit -= SHMEM_NR_DIRECT; idx = (idx > SHMEM_NR_DIRECT)? (idx - SHMEM_NR_DIRECT): 0; offset = idx % ENTRIES_PER_PAGE; @@ -533,8 +585,14 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) if (*dir) { diroff = ((idx - ENTRIES_PER_PAGEPAGE/2) % ENTRIES_PER_PAGEPAGE) / ENTRIES_PER_PAGE; - if (!diroff && !offset) { - *dir = NULL; + if (!diroff && !offset && upper_limit >= stage) { + if (needs_lock) { + spin_lock(needs_lock); + *dir = NULL; + spin_unlock(needs_lock); + needs_lock = NULL; + } else + *dir = NULL; nr_pages_to_free++; list_add(&middir->lru, &pages_to_free); } @@ -560,39 +618,55 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) } stage = idx + ENTRIES_PER_PAGEPAGE; middir = *dir; - *dir = NULL; - nr_pages_to_free++; - list_add(&middir->lru, &pages_to_free); + if (punch_hole) + needs_lock = &info->lock; + if (upper_limit >= stage) { + if (needs_lock) { + spin_lock(needs_lock); + *dir = NULL; + spin_unlock(needs_lock); + needs_lock = NULL; + } else + *dir = NULL; + nr_pages_to_free++; + list_add(&middir->lru, &pages_to_free); + } shmem_dir_unmap(dir); cond_resched(); dir = shmem_dir_map(middir); diroff = 0; } + punch_lock = needs_lock; subdir = dir[diroff]; - if (subdir && page_private(subdir)) { + if (subdir && !offset && upper_limit-idx >= ENTRIES_PER_PAGE) { + if (needs_lock) { + spin_lock(needs_lock); + dir[diroff] = NULL; + spin_unlock(needs_lock); + punch_lock = NULL; + } else + dir[diroff] = NULL; + nr_pages_to_free++; + list_add(&subdir->lru, &pages_to_free); + } + if (subdir && page_private(subdir) /* has swap entries */) { size = limit - idx; if (size > ENTRIES_PER_PAGE) size = ENTRIES_PER_PAGE; freed = shmem_map_and_free_swp(subdir, - offset, size, &dir); + offset, size, &dir, punch_lock); if (!dir) dir = shmem_dir_map(middir); nr_swaps_freed += freed; - if (offset) + if (offset || punch_lock) { spin_lock(&info->lock); - set_page_private(subdir, page_private(subdir) - freed); - if (offset) + set_page_private(subdir, + page_private(subdir) - freed); spin_unlock(&info->lock); - if (!punch_hole) - BUG_ON(page_private(subdir) > offset); - } - if (offset) - offset = 0; - else if (subdir && !page_private(subdir)) { - dir[diroff] = NULL; - nr_pages_to_free++; - list_add(&subdir->lru, &pages_to_free); + } else + BUG_ON(page_private(subdir) != freed); } + offset = 0; } done1: shmem_dir_unmap(dir); @@ -604,8 +678,16 @@ done2: * generic_delete_inode did it, before we lowered next_index. * Also, though shmem_getpage checks i_size before adding to * cache, no recheck after: so fix the narrow window there too. + * + * Recalling truncate_inode_pages_range and unmap_mapping_range + * every time for punch_hole (which never got a chance to clear + * SHMEM_PAGEIN at the start of vmtruncate_range) is expensive, + * yet hardly ever necessary: try to optimize them out later. */ truncate_inode_pages_range(inode->i_mapping, start, end); + if (punch_hole) + unmap_mapping_range(inode->i_mapping, start, + end - start, 1); } spin_lock(&info->lock); @@ -636,7 +718,7 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr) struct page *page = NULL; int error; - if (attr->ia_valid & ATTR_SIZE) { + if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { if (attr->ia_size < inode->i_size) { /* * If truncating down to a partial page, then @@ -669,6 +751,10 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr) error = inode_change_ok(inode, attr); if (!error) error = inode_setattr(inode, attr); +#ifdef CONFIG_TMPFS_POSIX_ACL + if (!error && (attr->ia_valid & ATTR_MODE)) + error = generic_acl_chmod(inode, &shmem_acl_ops); +#endif if (page) page_cache_release(page); return error; @@ -829,6 +915,21 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) struct inode *inode; BUG_ON(!PageLocked(page)); + /* + * shmem_backing_dev_info's capabilities prevent regular writeback or + * sync from ever calling shmem_writepage; but a stacking filesystem + * may use the ->writepage of its underlying filesystem, in which case + * we want to do nothing when that underlying filesystem is tmpfs + * (writing out to swap is useful as a response to memory pressure, but + * of no use to stabilize the data) - just redirty the page, unlock it + * and claim success in this case. AOP_WRITEPAGE_ACTIVATE, and the + * page_mapped check below, must be avoided unless we're in reclaim. + */ + if (!wbc->for_reclaim) { + set_page_dirty(page); + unlock_page(page); + return 0; + } BUG_ON(page_mapped(page)); mapping = page->mapping; @@ -875,7 +976,7 @@ redirty: } #ifdef CONFIG_NUMA -static int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes) +static inline int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes) { char *nodelist = strchr(value, ':'); int err = 1; @@ -885,6 +986,8 @@ static int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes) *nodelist++ = '\0'; if (nodelist_parse(nodelist, *policy_nodes)) goto out; + if (!nodes_subset(*policy_nodes, node_states[N_HIGH_MEMORY])) + goto out; } if (!strcmp(value, "default")) { *policy = MPOL_DEFAULT; @@ -908,9 +1011,11 @@ static int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes) err = 0; } else if (!strcmp(value, "interleave")) { *policy = MPOL_INTERLEAVE; - /* Default to nodes online if no nodelist */ + /* + * Default to online nodes with memory if no nodelist + */ if (!nodelist) - *policy_nodes = node_online_map; + *policy_nodes = node_states[N_HIGH_MEMORY]; err = 0; } out: @@ -936,8 +1041,8 @@ static struct page *shmem_swapin_async(struct shared_policy *p, return page; } -struct page *shmem_swapin(struct shmem_inode_info *info, swp_entry_t entry, - unsigned long idx) +static struct page *shmem_swapin(struct shmem_inode_info *info, + swp_entry_t entry, unsigned long idx) { struct shared_policy *p = &info->policy; int i, num; @@ -967,12 +1072,13 @@ shmem_alloc_page(gfp_t gfp, struct shmem_inode_info *info, pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx); pvma.vm_pgoff = idx; pvma.vm_end = PAGE_SIZE; - page = alloc_page_vma(gfp | __GFP_ZERO, &pvma, 0); + page = alloc_page_vma(gfp, &pvma, 0); mpol_free(pvma.vm_policy); return page; } #else -static inline int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes) +static inline int shmem_parse_mpol(char *value, int *policy, + nodemask_t *policy_nodes) { return 1; } @@ -987,7 +1093,7 @@ shmem_swapin(struct shmem_inode_info *info,swp_entry_t entry,unsigned long idx) static inline struct page * shmem_alloc_page(gfp_t gfp,struct shmem_inode_info *info, unsigned long idx) { - return alloc_page(gfp | __GFP_ZERO); + return alloc_page(gfp); } #endif @@ -1012,13 +1118,17 @@ static int shmem_getpage(struct inode *inode, unsigned long idx, if (idx >= SHMEM_MAX_INDEX) return -EFBIG; + + if (type) + *type = 0; + /* * Normally, filepage is NULL on entry, and either found * uptodate immediately, or allocated and zeroed, or read * in under swappage, which is then assigned to filepage. - * But shmem_prepare_write passes in a locked filepage, - * which may be found not uptodate by other callers too, - * and may need to be copied from the swappage read in. + * But shmem_readpage and shmem_write_begin pass in a locked + * filepage, which may be found not uptodate by other callers + * too, and may need to be copied from the swappage read in. */ repeat: if (!filepage) @@ -1044,12 +1154,12 @@ repeat: swappage = lookup_swap_cache(swap); if (!swappage) { shmem_swp_unmap(entry); - spin_unlock(&info->lock); /* here we actually do the io */ - if (type && *type == VM_FAULT_MINOR) { - inc_page_state(pgmajfault); - *type = VM_FAULT_MAJOR; + if (type && !(*type & VM_FAULT_MAJOR)) { + __count_vm_event(PGMAJFAULT); + *type |= VM_FAULT_MAJOR; } + spin_unlock(&info->lock); swappage = shmem_swapin(info, swap, idx); if (!swappage) { spin_lock(&info->lock); @@ -1079,14 +1189,6 @@ repeat: page_cache_release(swappage); goto repeat; } - if (!PageSwapCache(swappage)) { - /* Page migration has occured */ - shmem_swp_unmap(entry); - spin_unlock(&info->lock); - unlock_page(swappage); - page_cache_release(swappage); - goto repeat; - } if (PageWriteback(swappage)) { shmem_swp_unmap(entry); spin_unlock(&info->lock); @@ -1131,7 +1233,7 @@ repeat: page_cache_release(swappage); if (error == -ENOMEM) { /* let kswapd refresh zone for GFP_ATOMICs */ - blk_congestion_wait(WRITE, HZ/50); + congestion_wait(WRITE, HZ/50); } goto repeat; } @@ -1204,13 +1306,16 @@ repeat: info->alloced++; spin_unlock(&info->lock); + clear_highpage(filepage); flush_dcache_page(filepage); SetPageUptodate(filepage); } done: if (*pagep != filepage) { - unlock_page(filepage); *pagep = filepage; + if (sgp != SGP_FAULT) + unlock_page(filepage); + } return 0; @@ -1222,84 +1327,34 @@ failed: return error; } -struct page *shmem_nopage(struct vm_area_struct *vma, unsigned long address, int *type) +static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { - struct inode *inode = vma->vm_file->f_dentry->d_inode; - struct page *page = NULL; - unsigned long idx; + struct inode *inode = vma->vm_file->f_path.dentry->d_inode; int error; + int ret; - idx = (address - vma->vm_start) >> PAGE_SHIFT; - idx += vma->vm_pgoff; - idx >>= PAGE_CACHE_SHIFT - PAGE_SHIFT; - if (((loff_t) idx << PAGE_CACHE_SHIFT) >= i_size_read(inode)) - return NOPAGE_SIGBUS; + if (((loff_t)vmf->pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode)) + return VM_FAULT_SIGBUS; - error = shmem_getpage(inode, idx, &page, SGP_CACHE, type); + error = shmem_getpage(inode, vmf->pgoff, &vmf->page, SGP_FAULT, &ret); if (error) - return (error == -ENOMEM)? NOPAGE_OOM: NOPAGE_SIGBUS; + return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS); - mark_page_accessed(page); - return page; -} - -static int shmem_populate(struct vm_area_struct *vma, - unsigned long addr, unsigned long len, - pgprot_t prot, unsigned long pgoff, int nonblock) -{ - struct inode *inode = vma->vm_file->f_dentry->d_inode; - struct mm_struct *mm = vma->vm_mm; - enum sgp_type sgp = nonblock? SGP_QUICK: SGP_CACHE; - unsigned long size; - - size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; - if (pgoff >= size || pgoff + (len >> PAGE_SHIFT) > size) - return -EINVAL; - - while ((long) len > 0) { - struct page *page = NULL; - int err; - /* - * Will need changing if PAGE_CACHE_SIZE != PAGE_SIZE - */ - err = shmem_getpage(inode, pgoff, &page, sgp, NULL); - if (err) - return err; - /* Page may still be null, but only if nonblock was set. */ - if (page) { - mark_page_accessed(page); - err = install_page(mm, vma, addr, page, prot); - if (err) { - page_cache_release(page); - return err; - } - } else if (vma->vm_flags & VM_NONLINEAR) { - /* No page was found just because we can't read it in - * now (being here implies nonblock != 0), but the page - * may exist, so set the PTE to fault it in later. */ - err = install_file_pte(mm, vma, addr, pgoff, prot); - if (err) - return err; - } - - len -= PAGE_SIZE; - addr += PAGE_SIZE; - pgoff++; - } - return 0; + mark_page_accessed(vmf->page); + return ret | VM_FAULT_LOCKED; } #ifdef CONFIG_NUMA -int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new) +static int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new) { - struct inode *i = vma->vm_file->f_dentry->d_inode; + struct inode *i = vma->vm_file->f_path.dentry->d_inode; return mpol_set_shared_policy(&SHMEM_I(i)->policy, vma, new); } -struct mempolicy * -shmem_get_policy(struct vm_area_struct *vma, unsigned long addr) +static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma, + unsigned long addr) { - struct inode *i = vma->vm_file->f_dentry->d_inode; + struct inode *i = vma->vm_file->f_path.dentry->d_inode; unsigned long idx; idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; @@ -1309,7 +1364,7 @@ shmem_get_policy(struct vm_area_struct *vma, unsigned long addr) int shmem_lock(struct file *file, int lock, struct user_struct *user) { - struct inode *inode = file->f_dentry->d_inode; + struct inode *inode = file->f_path.dentry->d_inode; struct shmem_inode_info *info = SHMEM_I(inode); int retval = -ENOMEM; @@ -1329,10 +1384,11 @@ out_nomem: return retval; } -int shmem_mmap(struct file *file, struct vm_area_struct *vma) +static int shmem_mmap(struct file *file, struct vm_area_struct *vma) { file_accessed(file); vma->vm_ops = &shmem_vm_ops; + vma->vm_flags |= VM_CAN_NONLINEAR; return 0; } @@ -1358,11 +1414,11 @@ shmem_get_inode(struct super_block *sb, int mode, dev_t dev) inode->i_mode = mode; inode->i_uid = current->fsuid; inode->i_gid = current->fsgid; - inode->i_blksize = PAGE_CACHE_SIZE; inode->i_blocks = 0; inode->i_mapping->a_ops = &shmem_aops; inode->i_mapping->backing_dev_info = &shmem_backing_dev_info; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; + inode->i_generation = get_seconds(); info = SHMEM_I(inode); memset(info, 0, (char *)inode - (char *)info); spin_lock_init(&info->lock); @@ -1370,6 +1426,7 @@ shmem_get_inode(struct super_block *sb, int mode, dev_t dev) switch (mode & S_IFMT) { default: + inode->i_op = &shmem_special_inode_operations; init_special_inode(inode, mode, dev); break; case S_IFREG: @@ -1379,7 +1436,7 @@ shmem_get_inode(struct super_block *sb, int mode, dev_t dev) &sbinfo->policy_nodes); break; case S_IFDIR: - inode->i_nlink++; + inc_nlink(inode); /* Some things misbehave if size == 0 on a directory */ inode->i_size = 2 * BOGO_DIRENT_SIZE; inode->i_op = &shmem_dir_inode_operations; @@ -1403,24 +1460,53 @@ shmem_get_inode(struct super_block *sb, int mode, dev_t dev) } #ifdef CONFIG_TMPFS -static struct inode_operations shmem_symlink_inode_operations; -static struct inode_operations shmem_symlink_inline_operations; +static const struct inode_operations shmem_symlink_inode_operations; +static const struct inode_operations shmem_symlink_inline_operations; /* - * Normally tmpfs makes no use of shmem_prepare_write, but it - * lets a tmpfs file be used read-write below the loop driver. + * Normally tmpfs avoids the use of shmem_readpage and shmem_write_begin; + * but providing them allows a tmpfs file to be used for splice, sendfile, and + * below the loop driver, in the generic fashion that many filesystems support. */ -static int -shmem_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to) +static int shmem_readpage(struct file *file, struct page *page) { struct inode *inode = page->mapping->host; - return shmem_getpage(inode, page->index, &page, SGP_WRITE, NULL); + int error = shmem_getpage(inode, page->index, &page, SGP_CACHE, NULL); + unlock_page(page); + return error; +} + +static int +shmem_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + struct inode *inode = mapping->host; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + *pagep = NULL; + return shmem_getpage(inode, index, pagep, SGP_WRITE, NULL); +} + +static int +shmem_write_end(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) +{ + struct inode *inode = mapping->host; + + set_page_dirty(page); + page_cache_release(page); + + if (pos+copied > inode->i_size) + i_size_write(inode, pos+copied); + + return copied; } static ssize_t shmem_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct inode *inode = file->f_dentry->d_inode; + struct inode *inode = file->f_path.dentry->d_inode; loff_t pos; unsigned long written; ssize_t err; @@ -1440,7 +1526,7 @@ shmem_file_write(struct file *file, const char __user *buf, size_t count, loff_t if (err || !count) goto out; - err = remove_suid(file->f_dentry); + err = remove_suid(file->f_path.dentry); if (err) goto out; @@ -1522,7 +1608,7 @@ out: static void do_shmem_file_read(struct file *filp, loff_t *ppos, read_descriptor_t *desc, read_actor_t actor) { - struct inode *inode = filp->f_dentry->d_inode; + struct inode *inode = filp->f_path.dentry->d_inode; struct address_space *mapping = inode->i_mapping; unsigned long index, offset; @@ -1633,28 +1719,9 @@ static ssize_t shmem_file_read(struct file *filp, char __user *buf, size_t count return desc.error; } -static ssize_t shmem_file_sendfile(struct file *in_file, loff_t *ppos, - size_t count, read_actor_t actor, void *target) -{ - read_descriptor_t desc; - - if (!count) - return 0; - - desc.written = 0; - desc.count = count; - desc.arg.data = target; - desc.error = 0; - - do_shmem_file_read(in_file, ppos, &desc, actor); - if (desc.written) - return desc.written; - return desc.error; -} - -static int shmem_statfs(struct super_block *sb, struct kstatfs *buf) +static int shmem_statfs(struct dentry *dentry, struct kstatfs *buf) { - struct shmem_sb_info *sbinfo = SHMEM_SB(sb); + struct shmem_sb_info *sbinfo = SHMEM_SB(dentry->d_sb); buf->f_type = TMPFS_MAGIC; buf->f_bsize = PAGE_CACHE_SIZE; @@ -1690,7 +1757,11 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) iput(inode); return error; } - error = 0; + } + error = shmem_acl_init(inode, dir); + if (error) { + iput(inode); + return error; } if (dir->i_mode & S_ISGID) { inode->i_gid = dir->i_gid; @@ -1711,7 +1782,7 @@ static int shmem_mkdir(struct inode *dir, struct dentry *dentry, int mode) if ((error = shmem_mknod(dir, dentry, mode | S_IFDIR, 0))) return error; - dir->i_nlink++; + inc_nlink(dir); return 0; } @@ -1746,7 +1817,7 @@ static int shmem_link(struct dentry *old_dentry, struct inode *dir, struct dentr dir->i_size += BOGO_DIRENT_SIZE; inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME; - inode->i_nlink++; + inc_nlink(inode); atomic_inc(&inode->i_count); /* New dentry reference */ dget(dentry); /* Extra pinning count for the created dentry */ d_instantiate(dentry, inode); @@ -1768,7 +1839,7 @@ static int shmem_unlink(struct inode *dir, struct dentry *dentry) dir->i_size -= BOGO_DIRENT_SIZE; inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME; - inode->i_nlink--; + drop_nlink(inode); dput(dentry); /* Undo the count from "create" - this does all the work */ return 0; } @@ -1778,7 +1849,8 @@ static int shmem_rmdir(struct inode *dir, struct dentry *dentry) if (!simple_empty(dentry)) return -ENOTEMPTY; - dir->i_nlink--; + drop_nlink(dentry->d_inode); + drop_nlink(dir); return shmem_unlink(dir, dentry); } @@ -1799,10 +1871,10 @@ static int shmem_rename(struct inode *old_dir, struct dentry *old_dentry, struct if (new_dentry->d_inode) { (void) shmem_unlink(new_dir, new_dentry); if (they_are_dirs) - old_dir->i_nlink--; + drop_nlink(old_dir); } else if (they_are_dirs) { - old_dir->i_nlink--; - new_dir->i_nlink++; + drop_nlink(old_dir); + inc_nlink(new_dir); } old_dir->i_size -= BOGO_DIRENT_SIZE; @@ -1892,18 +1964,135 @@ static void shmem_put_link(struct dentry *dentry, struct nameidata *nd, void *co } } -static struct inode_operations shmem_symlink_inline_operations = { +static const struct inode_operations shmem_symlink_inline_operations = { .readlink = generic_readlink, .follow_link = shmem_follow_link_inline, }; -static struct inode_operations shmem_symlink_inode_operations = { +static const struct inode_operations shmem_symlink_inode_operations = { .truncate = shmem_truncate, .readlink = generic_readlink, .follow_link = shmem_follow_link, .put_link = shmem_put_link, }; +#ifdef CONFIG_TMPFS_POSIX_ACL +/** + * Superblocks without xattr inode operations will get security.* xattr + * support from the VFS "for free". As soon as we have any other xattrs + * like ACLs, we also need to implement the security.* handlers at + * filesystem level, though. + */ + +static size_t shmem_xattr_security_list(struct inode *inode, char *list, + size_t list_len, const char *name, + size_t name_len) +{ + return security_inode_listsecurity(inode, list, list_len); +} + +static int shmem_xattr_security_get(struct inode *inode, const char *name, + void *buffer, size_t size) +{ + if (strcmp(name, "") == 0) + return -EINVAL; + return security_inode_getsecurity(inode, name, buffer, size, + -EOPNOTSUPP); +} + +static int shmem_xattr_security_set(struct inode *inode, const char *name, + const void *value, size_t size, int flags) +{ + if (strcmp(name, "") == 0) + return -EINVAL; + return security_inode_setsecurity(inode, name, value, size, flags); +} + +static struct xattr_handler shmem_xattr_security_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .list = shmem_xattr_security_list, + .get = shmem_xattr_security_get, + .set = shmem_xattr_security_set, +}; + +static struct xattr_handler *shmem_xattr_handlers[] = { + &shmem_xattr_acl_access_handler, + &shmem_xattr_acl_default_handler, + &shmem_xattr_security_handler, + NULL +}; +#endif + +static struct dentry *shmem_get_parent(struct dentry *child) +{ + return ERR_PTR(-ESTALE); +} + +static int shmem_match(struct inode *ino, void *vfh) +{ + __u32 *fh = vfh; + __u64 inum = fh[2]; + inum = (inum << 32) | fh[1]; + return ino->i_ino == inum && fh[0] == ino->i_generation; +} + +static struct dentry *shmem_fh_to_dentry(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type) +{ + struct inode *inode; + struct dentry *dentry = NULL; + u64 inum = fid->raw[2]; + inum = (inum << 32) | fid->raw[1]; + + if (fh_len < 3) + return NULL; + + inode = ilookup5(sb, (unsigned long)(inum + fid->raw[0]), + shmem_match, fid->raw); + if (inode) { + dentry = d_find_alias(inode); + iput(inode); + } + + return dentry; +} + +static int shmem_encode_fh(struct dentry *dentry, __u32 *fh, int *len, + int connectable) +{ + struct inode *inode = dentry->d_inode; + + if (*len < 3) + return 255; + + if (hlist_unhashed(&inode->i_hash)) { + /* Unfortunately insert_inode_hash is not idempotent, + * so as we hash inodes here rather than at creation + * time, we need a lock to ensure we only try + * to do it once + */ + static DEFINE_SPINLOCK(lock); + spin_lock(&lock); + if (hlist_unhashed(&inode->i_hash)) + __insert_inode_hash(inode, + inode->i_ino + inode->i_generation); + spin_unlock(&lock); + } + + fh[0] = inode->i_generation; + fh[1] = inode->i_ino; + fh[2] = ((__u64)inode->i_ino) >> 32; + + *len = 3; + return 1; +} + +static const struct export_operations shmem_export_ops = { + .get_parent = shmem_get_parent, + .encode_fh = shmem_encode_fh, + .fh_to_dentry = shmem_fh_to_dentry, +}; + static int shmem_parse_options(char *options, int *mode, uid_t *uid, gid_t *gid, unsigned long *blocks, unsigned long *inodes, int *policy, nodemask_t *policy_nodes) @@ -2059,7 +2248,7 @@ static int shmem_fill_super(struct super_block *sb, unsigned long blocks = 0; unsigned long inodes = 0; int policy = MPOL_DEFAULT; - nodemask_t policy_nodes = node_online_map; + nodemask_t policy_nodes = node_states[N_HIGH_MEMORY]; #ifdef CONFIG_TMPFS /* @@ -2076,6 +2265,7 @@ static int shmem_fill_super(struct super_block *sb, &inodes, &policy, &policy_nodes)) return -EINVAL; } + sb->s_export_op = &shmem_export_ops; #else sb->s_flags |= MS_NOUSER; #endif @@ -2100,6 +2290,11 @@ static int shmem_fill_super(struct super_block *sb, sb->s_blocksize_bits = PAGE_CACHE_SHIFT; sb->s_magic = TMPFS_MAGIC; sb->s_op = &shmem_ops; + sb->s_time_gran = 1; +#ifdef CONFIG_TMPFS_POSIX_ACL + sb->s_xattr = shmem_xattr_handlers; + sb->s_flags |= MS_POSIXACL; +#endif inode = shmem_get_inode(sb, S_IFDIR | mode, 0); if (!inode) @@ -2119,12 +2314,12 @@ failed: return err; } -static kmem_cache_t *shmem_inode_cachep; +static struct kmem_cache *shmem_inode_cachep; static struct inode *shmem_alloc_inode(struct super_block *sb) { struct shmem_inode_info *p; - p = (struct shmem_inode_info *)kmem_cache_alloc(shmem_inode_cachep, SLAB_KERNEL); + p = (struct shmem_inode_info *)kmem_cache_alloc(shmem_inode_cachep, GFP_KERNEL); if (!p) return NULL; return &p->vfs_inode; @@ -2136,62 +2331,72 @@ static void shmem_destroy_inode(struct inode *inode) /* only struct inode is valid if it's an inline symlink */ mpol_free_shared_policy(&SHMEM_I(inode)->policy); } + shmem_acl_destroy_inode(inode); kmem_cache_free(shmem_inode_cachep, SHMEM_I(inode)); } -static void init_once(void *foo, kmem_cache_t *cachep, unsigned long flags) +static void init_once(struct kmem_cache *cachep, void *foo) { struct shmem_inode_info *p = (struct shmem_inode_info *) foo; - if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == - SLAB_CTOR_CONSTRUCTOR) { - inode_init_once(&p->vfs_inode); - } + inode_init_once(&p->vfs_inode); +#ifdef CONFIG_TMPFS_POSIX_ACL + p->i_acl = NULL; + p->i_default_acl = NULL; +#endif } static int init_inodecache(void) { shmem_inode_cachep = kmem_cache_create("shmem_inode_cache", sizeof(struct shmem_inode_info), - 0, 0, init_once, NULL); - if (shmem_inode_cachep == NULL) - return -ENOMEM; + 0, SLAB_PANIC, init_once); return 0; } static void destroy_inodecache(void) { - if (kmem_cache_destroy(shmem_inode_cachep)) - printk(KERN_INFO "shmem_inode_cache: not all structures were freed\n"); + kmem_cache_destroy(shmem_inode_cachep); } -static struct address_space_operations shmem_aops = { +static const struct address_space_operations shmem_aops = { .writepage = shmem_writepage, - .set_page_dirty = __set_page_dirty_nobuffers, + .set_page_dirty = __set_page_dirty_no_writeback, #ifdef CONFIG_TMPFS - .prepare_write = shmem_prepare_write, - .commit_write = simple_commit_write, + .readpage = shmem_readpage, + .write_begin = shmem_write_begin, + .write_end = shmem_write_end, #endif + .migratepage = migrate_page, }; -static struct file_operations shmem_file_operations = { +static const struct file_operations shmem_file_operations = { .mmap = shmem_mmap, #ifdef CONFIG_TMPFS .llseek = generic_file_llseek, .read = shmem_file_read, .write = shmem_file_write, .fsync = simple_sync_file, - .sendfile = shmem_file_sendfile, + .splice_read = generic_file_splice_read, + .splice_write = generic_file_splice_write, #endif }; -static struct inode_operations shmem_inode_operations = { +static const struct inode_operations shmem_inode_operations = { .truncate = shmem_truncate, .setattr = shmem_notify_change, .truncate_range = shmem_truncate_range, +#ifdef CONFIG_TMPFS_POSIX_ACL + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = generic_listxattr, + .removexattr = generic_removexattr, + .permission = shmem_permission, +#endif + }; -static struct inode_operations shmem_dir_inode_operations = { +static const struct inode_operations shmem_dir_inode_operations = { #ifdef CONFIG_TMPFS .create = shmem_create, .lookup = simple_lookup, @@ -2203,9 +2408,28 @@ static struct inode_operations shmem_dir_inode_operations = { .mknod = shmem_mknod, .rename = shmem_rename, #endif +#ifdef CONFIG_TMPFS_POSIX_ACL + .setattr = shmem_notify_change, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = generic_listxattr, + .removexattr = generic_removexattr, + .permission = shmem_permission, +#endif +}; + +static const struct inode_operations shmem_special_inode_operations = { +#ifdef CONFIG_TMPFS_POSIX_ACL + .setattr = shmem_notify_change, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = generic_listxattr, + .removexattr = generic_removexattr, + .permission = shmem_permission, +#endif }; -static struct super_operations shmem_ops = { +static const struct super_operations shmem_ops = { .alloc_inode = shmem_alloc_inode, .destroy_inode = shmem_destroy_inode, #ifdef CONFIG_TMPFS @@ -2218,8 +2442,7 @@ static struct super_operations shmem_ops = { }; static struct vm_operations_struct shmem_vm_ops = { - .nopage = shmem_nopage, - .populate = shmem_populate, + .fault = shmem_fault, #ifdef CONFIG_NUMA .set_policy = shmem_set_policy, .get_policy = shmem_get_policy, @@ -2227,10 +2450,10 @@ static struct vm_operations_struct shmem_vm_ops = { }; -static struct super_block *shmem_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) +static int shmem_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data, struct vfsmount *mnt) { - return get_sb_nodev(fs_type, flags, data, shmem_fill_super); + return get_sb_nodev(fs_type, flags, data, shmem_fill_super, mnt); } static struct file_system_type tmpfs_fs_type = { @@ -2245,6 +2468,10 @@ static int __init init_tmpfs(void) { int error; + error = bdi_init(&shmem_backing_dev_info); + if (error) + goto out4; + error = init_inodecache(); if (error) goto out3; @@ -2254,10 +2481,8 @@ static int __init init_tmpfs(void) printk(KERN_ERR "Could not register tmpfs\n"); goto out2; } -#ifdef CONFIG_TMPFS - devfs_mk_dir("shm"); -#endif - shm_mnt = do_kern_mount(tmpfs_fs_type.name, MS_NOUSER, + + shm_mnt = vfs_kern_mount(&tmpfs_fs_type, MS_NOUSER, tmpfs_fs_type.name, NULL); if (IS_ERR(shm_mnt)) { error = PTR_ERR(shm_mnt); @@ -2271,6 +2496,8 @@ out1: out2: destroy_inodecache(); out3: + bdi_destroy(&shmem_backing_dev_info); +out4: shm_mnt = ERR_PTR(error); return error; } @@ -2323,11 +2550,8 @@ struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags) d_instantiate(dentry, inode); inode->i_size = size; inode->i_nlink = 0; /* It is unlinked */ - file->f_vfsmnt = mntget(shm_mnt); - file->f_dentry = dentry; - file->f_mapping = inode->i_mapping; - file->f_op = &shmem_file_operations; - file->f_mode = FMODE_WRITE | FMODE_READ; + init_file(file, shm_mnt, dentry, FMODE_WRITE | FMODE_READ, + &shmem_file_operations); return file; close_file: