On Tue, Nov 08, 2022 at 02:30:09PM +0100, Lukas Czerner wrote:
> Implement user and group quota support for tmpfs using system quota file
> in vfsv0 quota format. Because everything in tmpfs is temporary and as a
> result is lost on umount, the quota files are initialized on every
> mount. This also goes for quota limits, that needs to be set up after
> every mount.
>
> The quota support in tmpfs is well separated from the rest of the
> filesystem and is only enabled using mount option -o quota (and
> usrquota and grpquota for compatibility reasons). Only quota accounting
> is enabled this way, enforcement needs to be enable by regular quota
> tools (using Q_QUOTAON ioctl).
>
> Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
> ---
> Documentation/filesystems/tmpfs.rst | 12 +
> include/linux/shmem_fs.h | 3 +
> mm/shmem.c | 361 ++++++++++++++++++++++++++--
> 3 files changed, 353 insertions(+), 23 deletions(-)
>
> diff --git a/Documentation/filesystems/tmpfs.rst b/Documentation/filesystems/tmpfs.rst
> index 0408c245785e..9c4f228ef4f3 100644
> --- a/Documentation/filesystems/tmpfs.rst
> +++ b/Documentation/filesystems/tmpfs.rst
> @@ -86,6 +86,18 @@ use up all the memory on the machine; but enhances the scalability of
> that instance in a system with many CPUs making intensive use of it.
>
>
> +tmpfs also supports quota with the following mount options
> +
> +======== =============================================================
> +quota Quota accounting is enabled on the mount. Tmpfs is using
> + hidden system quota files that are initialized on mount.
> + Quota limits can quota enforcement can be enabled using
> + standard quota tools.
> +usrquota Same as quota option. Exists for compatibility reasons.
> +grpquota Same as quota option. Exists for compatibility reasons.
I guess this is following ext* where group and user quota cannot be
enabled individually, nor is there a 'noenforce' mode?
Not complaining here, since it /does/ cut down on the number of mount
options. :)
> +======== =============================================================
> +
> +
> tmpfs has a mount option to set the NUMA memory allocation policy for
> all files in that instance (if CONFIG_NUMA is enabled) - which can be
> adjusted on the fly via 'mount -o remount ...'
> diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
> index d500ea967dc7..02a328c98d3a 100644
> --- a/include/linux/shmem_fs.h
> +++ b/include/linux/shmem_fs.h
> @@ -26,6 +26,9 @@ struct shmem_inode_info {
> atomic_t stop_eviction; /* hold when working on inode */
> struct timespec64 i_crtime; /* file creation time */
> unsigned int fsflags; /* flags for FS_IOC_[SG]ETFLAGS */
> +#ifdef CONFIG_QUOTA
> + struct dquot *i_dquot[MAXQUOTAS];
> +#endif
> struct inode vfs_inode;
> };
>
> diff --git a/mm/shmem.c b/mm/shmem.c
> index c1d8b8a1aa3b..ec16659c2255 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -79,6 +79,12 @@ static struct vfsmount *shm_mnt;
> #include <linux/userfaultfd_k.h>
> #include <linux/rmap.h>
> #include <linux/uuid.h>
> +#include <linux/quotaops.h>
> +/*
> + * Required for structures definitions and macros for quote file
> + * initialization.
> + */
> +#include <../fs/quota/quotaio_v2.h>
>
> #include <linux/uaccess.h>
>
> @@ -120,8 +126,13 @@ struct shmem_options {
> #define SHMEM_SEEN_INODES 2
> #define SHMEM_SEEN_HUGE 4
> #define SHMEM_SEEN_INUMS 8
> +#define SHMEM_SEEN_QUOTA 16
> };
>
> +static void shmem_set_inode_flags(struct inode *, unsigned int);
> +static struct inode *shmem_get_inode_noquota(struct super_block *,
> + struct inode *, umode_t, dev_t, unsigned long);
> +
> #ifdef CONFIG_TMPFS
> static unsigned long shmem_default_max_blocks(void)
> {
> @@ -136,6 +147,10 @@ static unsigned long shmem_default_max_inodes(void)
> }
> #endif
>
> +#if defined(CONFIG_TMPFS) && defined(CONFIG_QUOTA)
> +#define SHMEM_QUOTA_TMPFS
> +#endif
> +
> static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
> struct folio **foliop, enum sgp_type sgp,
> gfp_t gfp, struct vm_area_struct *vma,
> @@ -198,26 +213,34 @@ static inline void shmem_unacct_blocks(unsigned long flags, long pages)
> vm_unacct_memory(pages * VM_ACCT(PAGE_SIZE));
> }
>
> -static inline bool shmem_inode_acct_block(struct inode *inode, long pages)
> +static inline int shmem_inode_acct_block(struct inode *inode, long pages)
> {
> struct shmem_inode_info *info = SHMEM_I(inode);
> struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
> + int err = -ENOSPC;
>
> if (shmem_acct_block(info->flags, pages))
> - return false;
> + return err;
>
> if (sbinfo->max_blocks) {
> if (percpu_counter_compare(&sbinfo->used_blocks,
> sbinfo->max_blocks - pages) > 0)
> goto unacct;
> + if (dquot_alloc_block_nodirty(inode, pages)) {
> + err = -EDQUOT;
> + goto unacct;
> + }
> percpu_counter_add(&sbinfo->used_blocks, pages);
> + } else if (dquot_alloc_block_nodirty(inode, pages)) {
> + err = -EDQUOT;
> + goto unacct;
> }
>
> - return true;
> + return 0;
>
> unacct:
> shmem_unacct_blocks(info->flags, pages);
> - return false;
> + return err;
> }
>
> static inline void shmem_inode_unacct_blocks(struct inode *inode, long pages)
> @@ -225,6 +248,8 @@ static inline void shmem_inode_unacct_blocks(struct inode *inode, long pages)
> struct shmem_inode_info *info = SHMEM_I(inode);
> struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
>
> + dquot_free_block_nodirty(inode, pages);
> +
> if (sbinfo->max_blocks)
> percpu_counter_sub(&sbinfo->used_blocks, pages);
> shmem_unacct_blocks(info->flags, pages);
> @@ -247,6 +272,218 @@ bool vma_is_shmem(struct vm_area_struct *vma)
> static LIST_HEAD(shmem_swaplist);
> static DEFINE_MUTEX(shmem_swaplist_mutex);
>
> +#ifdef SHMEM_QUOTA_TMPFS
> +
> +#define SHMEM_MAXQUOTAS 2
> +
> +/*
> + * Define macros needed for quota file initialization.
> + */
> +#define MAX_IQ_TIME 604800 /* (7*24*60*60) 1 week */
> +#define MAX_DQ_TIME 604800 /* (7*24*60*60) 1 week */
> +#define QT_TREEOFF 1 /* Offset of tree in file in blocks */
> +#define QUOTABLOCK_BITS 10
> +#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
> +
> +static ssize_t shmem_quota_write_inode(struct inode *inode, int type,
> + const char *data, size_t len, loff_t off)
> +{
> + loff_t i_size = i_size_read(inode);
> + struct page *page = NULL;
> + unsigned long offset;
> + struct folio *folio;
> + int err = 0;
> + pgoff_t index;
> +
> + index = off >> PAGE_SHIFT;
> + offset = off & ~PAGE_MASK;
> +
> + /*
> + * We expect the write to fit into a single page
> + */
> + if (PAGE_SIZE - offset < len) {
> + pr_warn("tmpfs: quota write (off=%llu, len=%llu) doesn't fit into a single page\n",
> + (unsigned long long)off, (unsigned long long)len);
> + return -EIO;
> + }
> +
> + err = shmem_get_folio(inode, index, &folio, SGP_WRITE);
> + if (err)
> + return err;
> +
> + page = folio_file_page(folio, index);
> + if (PageHWPoison(page)) {
> + folio_unlock(folio);
> + folio_put(folio);
> + return -EIO;
> + }
> +
> + /* Write data, or zeroout the portion of the page */
> + if (data)
> + memcpy(page_address(page) + offset, data, len);
> + else
> + memset(page_address(page) + offset, 0, len);
> +
> + SetPageUptodate(page);
Don't we need to mark the /folio/ uptodate here? Or at least the head
page if the quota file got a THP?
Hm. shmem_write_end will SetPageUptodate on the head page if it's a
compound page, but it'll set_page_dirty to mark the whole folio dirty.
Now I'm confused completely. :(
OTOH I guess these are quota files, perhaps they simply don't need THP
anyway?
> + flush_dcache_folio(folio);
> + folio_mark_dirty(folio);
> + folio_unlock(folio);
> + folio_put(folio);
> +
> + if (i_size < off + len)
> + i_size_write(inode, off + len);
> + return err ? err : len;
> +}
> +
> +static ssize_t shmem_quota_write(struct super_block *sb, int type,
> + const char *data, size_t len, loff_t off)
> +{
> + struct inode *inode = sb_dqopt(sb)->files[type];
> +
> + return shmem_quota_write_inode(inode, type, data, len, off);
> +}
> +
> +static int shmem_enable_quotas(struct super_block *sb)
> +{
> + int type, err = 0;
> + struct inode *inode;
> + struct v2_disk_dqheader qheader;
> + struct v2_disk_dqinfo qinfo;
> + static const uint quota_magics[] = V2_INITQMAGICS;
> + static const uint quota_versions[] = V2_INITQVERSIONS;
> +
> + sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
> + for (type = 0; type < SHMEM_MAXQUOTAS; type++) {
> + inode = shmem_get_inode_noquota(sb, NULL, S_IFREG | 0777, 0,
> + VM_NORESERVE);
> + if (IS_ERR_OR_NULL(inode)) {
> + err = PTR_ERR(inode);
> + goto out_err;
> + }
> + inode->i_flags |= S_NOQUOTA;
> +
> + /* Initialize generic quota file header */
> + qheader.dqh_magic = cpu_to_le32(quota_magics[type]);
> + qheader.dqh_version = cpu_to_le32(quota_versions[type]);
> +
> + /* Initialize the quota file info structure */
> + qinfo.dqi_bgrace = cpu_to_le32(MAX_DQ_TIME);
> + qinfo.dqi_igrace = cpu_to_le32(MAX_IQ_TIME);
> + qinfo.dqi_flags = cpu_to_le32(0);
> + qinfo.dqi_blocks = cpu_to_le32(QT_TREEOFF + 1);
> + qinfo.dqi_free_blk = cpu_to_le32(0);
> + qinfo.dqi_free_entry = cpu_to_le32(0);
> +
> + /*
> + * Write out generic quota header, quota info structure and
> + * zeroout first tree block.
> + */
> + shmem_quota_write_inode(inode, type, (const char *)&qheader,
> + sizeof(qheader), 0);
Why is it not important to check error returns here?
> + shmem_quota_write_inode(inode, type, (const char *)&qinfo,
> + sizeof(qinfo), sizeof(qheader));
> + shmem_quota_write_inode(inode, type, 0,
> + QT_TREEOFF * QUOTABLOCK_SIZE,
> + QUOTABLOCK_SIZE);
> +
> + shmem_set_inode_flags(inode, FS_NOATIME_FL | FS_IMMUTABLE_FL);
> +
> + err = dquot_load_quota_inode(inode, type, QFMT_VFS_V1,
I wonder, what's the difference between quota v1 and v2? Wouldn't we
want the newer version?
> + DQUOT_USAGE_ENABLED);
> + iput(inode);
> + if (err)
> + goto out_err;
> + }
> + return 0;
> +
> +out_err:
> + pr_warn("tmpfs: failed to enable quota tracking (type=%d, err=%d)\n",
> + type, err);
> + for (type--; type >= 0; type--) {
> + inode = sb_dqopt(sb)->files[type];
> + if (inode)
> + inode = igrab(inode);
> + dquot_quota_off(sb, type);
> + if (inode)
> + iput(inode);
> + }
> + return err;
> +}
> +
> +static void shmem_disable_quotas(struct super_block *sb)
> +{
> + struct inode *inode = NULL;
> + int type;
> +
> + for (type = 0; type < SHMEM_MAXQUOTAS; type++) {
> + inode = sb_dqopt(sb)->files[type];
> + if (inode)
> + inode = igrab(inode);
> + dquot_quota_off(sb, type);
> + if (inode)
> + iput(inode);
> + }
> +}
> +
> +static ssize_t shmem_quota_read(struct super_block *sb, int type, char *data,
> + size_t len, loff_t off)
> +{
> + struct inode *inode = sb_dqopt(sb)->files[type];
> + loff_t i_size = i_size_read(inode);
> + struct folio *folio = NULL;
> + struct page *page = NULL;
> + unsigned long offset;
> + int tocopy, err = 0;
> + pgoff_t index;
> + size_t toread;
> +
> + index = off >> PAGE_SHIFT;
> + offset = off & ~PAGE_MASK;
> +
> + if (off > i_size)
> + return 0;
> + if (off+len > i_size)
> + len = i_size - off;
> + toread = len;
> + while (toread > 0) {
> + tocopy = PAGE_SIZE - offset < toread ?
> + PAGE_SIZE - offset : toread;
> +
> + err = shmem_get_folio(inode, index, &folio, SGP_READ);
> + if (err) {
> + if (err == -EINVAL)
> + err = 0;
> + return err;
> + }
> +
> + if (folio) {
folio && folio_test_uptodate() ?
> + folio_unlock(folio);
> + page = folio_file_page(folio, index);
> + if (PageHWPoison(page)) {
> + folio_put(folio);
> + return -EIO;
> + }
> + memcpy(data, page_address(page) + offset, tocopy);
> + folio_put(folio);
Also, I'm a little surprised that it's safe to read the contents of a
folio after unlocking it.
> + } else { /* A hole */
> + memset(data, 0, tocopy);
> + }
> +
> + offset = 0;
> + toread -= tocopy;
> + data += tocopy;
> + index++;
> + cond_resched();
> + }
> + return len;
> +}
> +
> +static struct dquot **shmem_get_dquots(struct inode *inode)
> +{
> + return SHMEM_I(inode)->i_dquot;
> +}
> +#endif /* SHMEM_QUOTA_TMPFS */
> +
> /*
> * shmem_reserve_inode() performs bookkeeping to reserve a shmem inode, and
> * produces a novel ino for the newly allocated inode.
> @@ -353,7 +590,6 @@ static void shmem_recalc_inode(struct inode *inode)
> freed = info->alloced - info->swapped - inode->i_mapping->nrpages;
> if (freed > 0) {
> info->alloced -= freed;
> - inode->i_blocks -= freed * BLOCKS_PER_PAGE;
I guess the quotaops helpers take care of the i_blocks updates now?
--D
> shmem_inode_unacct_blocks(inode, freed);
> }
> }
> @@ -363,7 +599,7 @@ bool shmem_charge(struct inode *inode, long pages)
> struct shmem_inode_info *info = SHMEM_I(inode);
> unsigned long flags;
>
> - if (!shmem_inode_acct_block(inode, pages))
> + if (shmem_inode_acct_block(inode, pages))
> return false;
>
> /* nrpages adjustment first, then shmem_recalc_inode() when balanced */
> @@ -371,7 +607,6 @@ bool shmem_charge(struct inode *inode, long pages)
>
> spin_lock_irqsave(&info->lock, flags);
> info->alloced += pages;
> - inode->i_blocks += pages * BLOCKS_PER_PAGE;
> shmem_recalc_inode(inode);
> spin_unlock_irqrestore(&info->lock, flags);
>
> @@ -387,7 +622,6 @@ void shmem_uncharge(struct inode *inode, long pages)
>
> spin_lock_irqsave(&info->lock, flags);
> info->alloced -= pages;
> - inode->i_blocks -= pages * BLOCKS_PER_PAGE;
> shmem_recalc_inode(inode);
> spin_unlock_irqrestore(&info->lock, flags);
>
> @@ -1119,6 +1353,13 @@ static int shmem_setattr(struct user_namespace *mnt_userns,
> }
> }
>
> + /* Transfer quota accounting */
> + if (i_uid_needs_update(mnt_userns, attr, inode) ||
> + i_gid_needs_update(mnt_userns, attr, inode))
> + error = dquot_transfer(mnt_userns, inode, attr);
> + if (error)
> + return error;
> +
> setattr_copy(&init_user_ns, inode, attr);
> if (attr->ia_valid & ATTR_MODE)
> error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
> @@ -1164,7 +1405,9 @@ static void shmem_evict_inode(struct inode *inode)
> simple_xattrs_free(&info->xattrs);
> WARN_ON(inode->i_blocks);
> shmem_free_inode(inode->i_sb);
> + dquot_free_inode(inode);
> clear_inode(inode);
> + dquot_drop(inode);
> }
>
> static int shmem_find_swap_entries(struct address_space *mapping,
> @@ -1569,14 +1812,14 @@ static struct folio *shmem_alloc_and_acct_folio(gfp_t gfp, struct inode *inode,
> {
> struct shmem_inode_info *info = SHMEM_I(inode);
> struct folio *folio;
> - int nr;
> - int err = -ENOSPC;
> + int nr, err;
>
> if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
> huge = false;
> nr = huge ? HPAGE_PMD_NR : 1;
>
> - if (!shmem_inode_acct_block(inode, nr))
> + err = shmem_inode_acct_block(inode, nr);
> + if (err)
> goto failed;
>
> if (huge)
> @@ -1949,7 +2192,6 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
>
> spin_lock_irq(&info->lock);
> info->alloced += folio_nr_pages(folio);
> - inode->i_blocks += (blkcnt_t)BLOCKS_PER_PAGE << folio_order(folio);
> shmem_recalc_inode(inode);
> spin_unlock_irq(&info->lock);
> alloced = true;
> @@ -2315,8 +2557,10 @@ static void shmem_set_inode_flags(struct inode *inode, unsigned int fsflags)
> #define shmem_initxattrs NULL
> #endif
>
> -static struct inode *shmem_get_inode(struct super_block *sb, struct inode *dir,
> - umode_t mode, dev_t dev, unsigned long flags)
> +static struct inode *shmem_get_inode_noquota(struct super_block *sb,
> + struct inode *dir,
> + umode_t mode, dev_t dev,
> + unsigned long flags)
> {
> struct inode *inode;
> struct shmem_inode_info *info;
> @@ -2384,6 +2628,35 @@ static struct inode *shmem_get_inode(struct super_block *sb, struct inode *dir,
> return inode;
> }
>
> +static struct inode *shmem_get_inode(struct super_block *sb, struct inode *dir,
> + umode_t mode, dev_t dev, unsigned long flags)
> +{
> + int err;
> + struct inode *inode;
> +
> + inode = shmem_get_inode_noquota(sb, dir, mode, dev, flags);
> + if (inode) {
> + err = dquot_initialize(inode);
> + if (err)
> + goto errout;
> +
> + err = dquot_alloc_inode(inode);
> + if (err) {
> + dquot_drop(inode);
> + goto errout;
> + }
> + }
> + return inode;
> +
> +errout:
> + inode->i_flags |= S_NOQUOTA;
> + iput(inode);
> + shmem_free_inode(sb);
> + if (err)
> + return ERR_PTR(err);
> + return NULL;
> +}
> +
> #ifdef CONFIG_USERFAULTFD
> int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
> pmd_t *dst_pmd,
> @@ -2403,7 +2676,7 @@ int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
> int ret;
> pgoff_t max_off;
>
> - if (!shmem_inode_acct_block(inode, 1)) {
> + if (shmem_inode_acct_block(inode, 1)) {
> /*
> * We may have got a page, returned -ENOENT triggering a retry,
> * and now we find ourselves with -ENOMEM. Release the page, to
> @@ -2487,7 +2760,6 @@ int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
>
> spin_lock_irq(&info->lock);
> info->alloced++;
> - inode->i_blocks += BLOCKS_PER_PAGE;
> shmem_recalc_inode(inode);
> spin_unlock_irq(&info->lock);
>
> @@ -2908,7 +3180,7 @@ shmem_mknod(struct user_namespace *mnt_userns, struct inode *dir,
> int error = -ENOSPC;
>
> inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE);
> - if (inode) {
> + if (!IS_ERR_OR_NULL(inode)) {
> error = simple_acl_create(dir, inode);
> if (error)
> goto out_iput;
> @@ -2924,7 +3196,8 @@ shmem_mknod(struct user_namespace *mnt_userns, struct inode *dir,
> inode_inc_iversion(dir);
> d_instantiate(dentry, inode);
> dget(dentry); /* Extra count - pin the dentry in core */
> - }
> + } else if (IS_ERR(inode))
> + error = PTR_ERR(inode);
> return error;
> out_iput:
> iput(inode);
> @@ -2939,7 +3212,7 @@ shmem_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
> int error = -ENOSPC;
>
> inode = shmem_get_inode(dir->i_sb, dir, mode, 0, VM_NORESERVE);
> - if (inode) {
> + if (!IS_ERR_OR_NULL(inode)) {
> error = security_inode_init_security(inode, dir,
> NULL,
> shmem_initxattrs, NULL);
> @@ -2949,7 +3222,8 @@ shmem_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
> if (error)
> goto out_iput;
> d_tmpfile(file, inode);
> - }
> + } else if (IS_ERR(inode))
> + error = PTR_ERR(inode);
> return finish_open_simple(file, error);
> out_iput:
> iput(inode);
> @@ -3126,6 +3400,8 @@ static int shmem_symlink(struct user_namespace *mnt_userns, struct inode *dir,
> VM_NORESERVE);
> if (!inode)
> return -ENOSPC;
> + else if (IS_ERR(inode))
> + return PTR_ERR(inode);
>
> error = security_inode_init_security(inode, dir, &dentry->d_name,
> shmem_initxattrs, NULL);
> @@ -3443,6 +3719,7 @@ enum shmem_param {
> Opt_uid,
> Opt_inode32,
> Opt_inode64,
> + Opt_quota,
> };
>
> static const struct constant_table shmem_param_enums_huge[] = {
> @@ -3464,6 +3741,9 @@ const struct fs_parameter_spec shmem_fs_parameters[] = {
> fsparam_u32 ("uid", Opt_uid),
> fsparam_flag ("inode32", Opt_inode32),
> fsparam_flag ("inode64", Opt_inode64),
> + fsparam_flag ("quota", Opt_quota),
> + fsparam_flag ("usrquota", Opt_quota),
> + fsparam_flag ("grpquota", Opt_quota),
> {}
> };
>
> @@ -3547,6 +3827,13 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param)
> ctx->full_inums = true;
> ctx->seen |= SHMEM_SEEN_INUMS;
> break;
> + case Opt_quota:
> +#ifdef CONFIG_QUOTA
> + ctx->seen |= SHMEM_SEEN_QUOTA;
> +#else
> + goto unsupported_parameter;
> +#endif
> + break;
> }
> return 0;
>
> @@ -3646,6 +3933,12 @@ static int shmem_reconfigure(struct fs_context *fc)
> goto out;
> }
>
> + if (ctx->seen & SHMEM_SEEN_QUOTA &&
> + !sb_any_quota_loaded(fc->root->d_sb)) {
> + err = "Cannot enable quota on remount";
> + goto out;
> + }
> +
> if (ctx->seen & SHMEM_SEEN_HUGE)
> sbinfo->huge = ctx->huge;
> if (ctx->seen & SHMEM_SEEN_INUMS)
> @@ -3728,6 +4021,9 @@ static void shmem_put_super(struct super_block *sb)
> {
> struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
>
> +#ifdef SHMEM_QUOTA_TMPFS
> + shmem_disable_quotas(sb);
> +#endif
> free_percpu(sbinfo->ino_batch);
> percpu_counter_destroy(&sbinfo->used_blocks);
> mpol_put(sbinfo->mpol);
> @@ -3805,14 +4101,26 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
> #endif
> uuid_gen(&sb->s_uuid);
>
> +#ifdef SHMEM_QUOTA_TMPFS
> + if (ctx->seen & SHMEM_SEEN_QUOTA) {
> + sb->dq_op = &dquot_operations;
> + sb->s_qcop = &dquot_quotactl_sysfile_ops;
> + sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
> +
> + if (shmem_enable_quotas(sb))
> + goto failed;
> + }
> +#endif /* SHMEM_QUOTA_TMPFS */
> +
> inode = shmem_get_inode(sb, NULL, S_IFDIR | sbinfo->mode, 0, VM_NORESERVE);
> - if (!inode)
> + if (IS_ERR_OR_NULL(inode))
> goto failed;
> inode->i_uid = sbinfo->uid;
> inode->i_gid = sbinfo->gid;
> sb->s_root = d_make_root(inode);
> if (!sb->s_root)
> goto failed;
> +
> return 0;
>
> failed:
> @@ -3976,7 +4284,12 @@ static const struct super_operations shmem_ops = {
> #ifdef CONFIG_TMPFS
> .statfs = shmem_statfs,
> .show_options = shmem_show_options,
> -#endif
> +#ifdef CONFIG_QUOTA
> + .quota_read = shmem_quota_read,
> + .quota_write = shmem_quota_write,
> + .get_dquots = shmem_get_dquots,
> +#endif /* CONFIG_QUOTA */
> +#endif /* CONFIG_TMPFS */
> .evict_inode = shmem_evict_inode,
> .drop_inode = generic_delete_inode,
> .put_super = shmem_put_super,
> @@ -4196,8 +4509,10 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
>
> inode = shmem_get_inode(mnt->mnt_sb, NULL, S_IFREG | S_IRWXUGO, 0,
> flags);
> - if (unlikely(!inode)) {
> + if (IS_ERR_OR_NULL(inode)) {
> shmem_unacct_size(flags, size);
> + if (IS_ERR(inode))
> + return (struct file *)inode;
> return ERR_PTR(-ENOSPC);
> }
> inode->i_flags |= i_flags;
> --
> 2.38.1
>
