fs/ntfs3: Reduce stack usage
authorKonstantin Komarov <almaz.alexandrovich@paragon-software.com>
Fri, 24 Nov 2023 08:42:04 +0000 (11:42 +0300)
committerKonstantin Komarov <almaz.alexandrovich@paragon-software.com>
Wed, 6 Dec 2023 14:46:09 +0000 (17:46 +0300)
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
fs/ntfs3/fslog.c

index 98ccb66..7dbb000 100644 (file)
@@ -974,6 +974,16 @@ skip_looking:
        return e;
 }
 
+struct restart_info {
+       u64 last_lsn;
+       struct RESTART_HDR *r_page;
+       u32 vbo;
+       bool chkdsk_was_run;
+       bool valid_page;
+       bool initialized;
+       bool restart;
+};
+
 #define RESTART_SINGLE_PAGE_IO cpu_to_le16(0x0001)
 
 #define NTFSLOG_WRAPPED 0x00000001
@@ -987,6 +997,7 @@ struct ntfs_log {
        struct ntfs_inode *ni;
 
        u32 l_size;
+       u32 orig_file_size;
        u32 sys_page_size;
        u32 sys_page_mask;
        u32 page_size;
@@ -1040,6 +1051,8 @@ struct ntfs_log {
 
        struct CLIENT_ID client_id;
        u32 client_undo_commit;
+
+       struct restart_info rst_info, rst_info2;
 };
 
 static inline u32 lsn_to_vbo(struct ntfs_log *log, const u64 lsn)
@@ -1105,16 +1118,6 @@ static inline bool verify_client_lsn(struct ntfs_log *log,
               lsn <= le64_to_cpu(log->ra->current_lsn) && lsn;
 }
 
-struct restart_info {
-       u64 last_lsn;
-       struct RESTART_HDR *r_page;
-       u32 vbo;
-       bool chkdsk_was_run;
-       bool valid_page;
-       bool initialized;
-       bool restart;
-};
-
 static int read_log_page(struct ntfs_log *log, u32 vbo,
                         struct RECORD_PAGE_HDR **buffer, bool *usa_error)
 {
@@ -1176,7 +1179,7 @@ out:
  * restart page header. It will stop the first time we find a
  * valid page header.
  */
-static int log_read_rst(struct ntfs_log *log, u32 l_size, bool first,
+static int log_read_rst(struct ntfs_log *log, bool first,
                        struct restart_info *info)
 {
        u32 skip, vbo;
@@ -1192,7 +1195,7 @@ static int log_read_rst(struct ntfs_log *log, u32 l_size, bool first,
        }
 
        /* Loop continuously until we succeed. */
-       for (; vbo < l_size; vbo = 2 * vbo + skip, skip = 0) {
+       for (; vbo < log->l_size; vbo = 2 * vbo + skip, skip = 0) {
                bool usa_error;
                bool brst, bchk;
                struct RESTART_AREA *ra;
@@ -1285,22 +1288,17 @@ check_result:
 /*
  * Ilog_init_pg_hdr - Init @log from restart page header.
  */
-static void log_init_pg_hdr(struct ntfs_log *log, u32 sys_page_size,
-                           u32 page_size, u16 major_ver, u16 minor_ver)
+static void log_init_pg_hdr(struct ntfs_log *log, u16 major_ver, u16 minor_ver)
 {
-       log->sys_page_size = sys_page_size;
-       log->sys_page_mask = sys_page_size - 1;
-       log->page_size = page_size;
-       log->page_mask = page_size - 1;
-       log->page_bits = blksize_bits(page_size);
+       log->sys_page_size = log->page_size;
+       log->sys_page_mask = log->page_mask;
 
        log->clst_per_page = log->page_size >> log->ni->mi.sbi->cluster_bits;
        if (!log->clst_per_page)
                log->clst_per_page = 1;
 
-       log->first_page = major_ver >= 2 ?
-                                 0x22 * page_size :
-                                 ((sys_page_size << 1) + (page_size << 1));
+       log->first_page = major_ver >= 2 ? 0x22 * log->page_size :
+                                          4 * log->page_size;
        log->major_ver = major_ver;
        log->minor_ver = minor_ver;
 }
@@ -1308,12 +1306,11 @@ static void log_init_pg_hdr(struct ntfs_log *log, u32 sys_page_size,
 /*
  * log_create - Init @log in cases when we don't have a restart area to use.
  */
-static void log_create(struct ntfs_log *log, u32 l_size, const u64 last_lsn,
+static void log_create(struct ntfs_log *log, const u64 last_lsn,
                       u32 open_log_count, bool wrapped, bool use_multi_page)
 {
-       log->l_size = l_size;
        /* All file offsets must be quadword aligned. */
-       log->file_data_bits = blksize_bits(l_size) - 3;
+       log->file_data_bits = blksize_bits(log->l_size) - 3;
        log->seq_num_mask = (8 << log->file_data_bits) - 1;
        log->seq_num_bits = sizeof(u64) * 8 - log->file_data_bits;
        log->seq_num = (last_lsn >> log->file_data_bits) + 2;
@@ -3720,10 +3717,8 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
        struct ntfs_sb_info *sbi = ni->mi.sbi;
        struct ntfs_log *log;
 
-       struct restart_info rst_info, rst_info2;
-       u64 rec_lsn, ra_lsn, checkpt_lsn = 0, rlsn = 0;
+       u64 rec_lsn, checkpt_lsn = 0, rlsn = 0;
        struct ATTR_NAME_ENTRY *attr_names = NULL;
-       struct ATTR_NAME_ENTRY *ane;
        struct RESTART_TABLE *dptbl = NULL;
        struct RESTART_TABLE *trtbl = NULL;
        const struct RESTART_TABLE *rt;
@@ -3741,9 +3736,7 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
        struct TRANSACTION_ENTRY *tr;
        struct DIR_PAGE_ENTRY *dp;
        u32 i, bytes_per_attr_entry;
-       u32 l_size = ni->vfs_inode.i_size;
-       u32 orig_file_size = l_size;
-       u32 page_size, vbo, tail, off, dlen;
+       u32 vbo, tail, off, dlen;
        u32 saved_len, rec_len, transact_id;
        bool use_second_page;
        struct RESTART_AREA *ra2, *ra = NULL;
@@ -3758,52 +3751,50 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
        u16 t16;
        u32 t32;
 
-       /* Get the size of page. NOTE: To replay we can use default page. */
-#if PAGE_SIZE >= DefaultLogPageSize && PAGE_SIZE <= DefaultLogPageSize * 2
-       page_size = norm_file_page(PAGE_SIZE, &l_size, true);
-#else
-       page_size = norm_file_page(PAGE_SIZE, &l_size, false);
-#endif
-       if (!page_size)
-               return -EINVAL;
-
        log = kzalloc(sizeof(struct ntfs_log), GFP_NOFS);
        if (!log)
                return -ENOMEM;
 
        log->ni = ni;
-       log->l_size = l_size;
-       log->one_page_buf = kmalloc(page_size, GFP_NOFS);
+       log->l_size = log->orig_file_size = ni->vfs_inode.i_size;
+
+       /* Get the size of page. NOTE: To replay we can use default page. */
+#if PAGE_SIZE >= DefaultLogPageSize && PAGE_SIZE <= DefaultLogPageSize * 2
+       log->page_size = norm_file_page(PAGE_SIZE, &log->l_size, true);
+#else
+       log->page_size = norm_file_page(PAGE_SIZE, &log->l_size, false);
+#endif
+       if (!log->page_size) {
+               err = -EINVAL;
+               goto out;
+       }
 
+       log->one_page_buf = kmalloc(log->page_size, GFP_NOFS);
        if (!log->one_page_buf) {
                err = -ENOMEM;
                goto out;
        }
 
-       log->page_size = page_size;
-       log->page_mask = page_size - 1;
-       log->page_bits = blksize_bits(page_size);
+       log->page_mask = log->page_size - 1;
+       log->page_bits = blksize_bits(log->page_size);
 
        /* Look for a restart area on the disk. */
-       memset(&rst_info, 0, sizeof(struct restart_info));
-       err = log_read_rst(log, l_size, true, &rst_info);
+       err = log_read_rst(log, true, &log->rst_info);
        if (err)
                goto out;
 
        /* remember 'initialized' */
-       *initialized = rst_info.initialized;
+       *initialized = log->rst_info.initialized;
 
-       if (!rst_info.restart) {
-               if (rst_info.initialized) {
+       if (!log->rst_info.restart) {
+               if (log->rst_info.initialized) {
                        /* No restart area but the file is not initialized. */
                        err = -EINVAL;
                        goto out;
                }
 
-               log_init_pg_hdr(log, page_size, page_size, 1, 1);
-               log_create(log, l_size, 0, get_random_u32(), false, false);
-
-               log->ra = ra;
+               log_init_pg_hdr(log, 1, 1);
+               log_create(log, 0, get_random_u32(), false, false);
 
                ra = log_create_ra(log);
                if (!ra) {
@@ -3820,25 +3811,26 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
         * If the restart offset above wasn't zero then we won't
         * look for a second restart.
         */
-       if (rst_info.vbo)
+       if (log->rst_info.vbo)
                goto check_restart_area;
 
-       memset(&rst_info2, 0, sizeof(struct restart_info));
-       err = log_read_rst(log, l_size, false, &rst_info2);
+       err = log_read_rst(log, false, &log->rst_info2);
        if (err)
                goto out;
 
        /* Determine which restart area to use. */
-       if (!rst_info2.restart || rst_info2.last_lsn <= rst_info.last_lsn)
+       if (!log->rst_info2.restart ||
+           log->rst_info2.last_lsn <= log->rst_info.last_lsn)
                goto use_first_page;
 
        use_second_page = true;
 
-       if (rst_info.chkdsk_was_run && page_size != rst_info.vbo) {
+       if (log->rst_info.chkdsk_was_run &&
+           log->page_size != log->rst_info.vbo) {
                struct RECORD_PAGE_HDR *sp = NULL;
                bool usa_error;
 
-               if (!read_log_page(log, page_size, &sp, &usa_error) &&
+               if (!read_log_page(log, log->page_size, &sp, &usa_error) &&
                    sp->rhdr.sign == NTFS_CHKD_SIGNATURE) {
                        use_second_page = false;
                }
@@ -3846,52 +3838,43 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
        }
 
        if (use_second_page) {
-               kfree(rst_info.r_page);
-               memcpy(&rst_info, &rst_info2, sizeof(struct restart_info));
-               rst_info2.r_page = NULL;
+               kfree(log->rst_info.r_page);
+               memcpy(&log->rst_info, &log->rst_info2,
+                      sizeof(struct restart_info));
+               log->rst_info2.r_page = NULL;
        }
 
 use_first_page:
-       kfree(rst_info2.r_page);
+       kfree(log->rst_info2.r_page);
 
 check_restart_area:
        /*
         * If the restart area is at offset 0, we want
         * to write the second restart area first.
         */
-       log->init_ra = !!rst_info.vbo;
+       log->init_ra = !!log->rst_info.vbo;
 
        /* If we have a valid page then grab a pointer to the restart area. */
-       ra2 = rst_info.valid_page ?
-                     Add2Ptr(rst_info.r_page,
-                             le16_to_cpu(rst_info.r_page->ra_off)) :
+       ra2 = log->rst_info.valid_page ?
+                     Add2Ptr(log->rst_info.r_page,
+                             le16_to_cpu(log->rst_info.r_page->ra_off)) :
                      NULL;
 
-       if (rst_info.chkdsk_was_run ||
+       if (log->rst_info.chkdsk_was_run ||
            (ra2 && ra2->client_idx[1] == LFS_NO_CLIENT_LE)) {
                bool wrapped = false;
                bool use_multi_page = false;
                u32 open_log_count;
 
                /* Do some checks based on whether we have a valid log page. */
-               if (!rst_info.valid_page) {
-                       open_log_count = get_random_u32();
-                       goto init_log_instance;
-               }
-               open_log_count = le32_to_cpu(ra2->open_log_count);
-
-               /*
-                * If the restart page size isn't changing then we want to
-                * check how much work we need to do.
-                */
-               if (page_size != le32_to_cpu(rst_info.r_page->sys_page_size))
-                       goto init_log_instance;
+               open_log_count = log->rst_info.valid_page ?
+                                        le32_to_cpu(ra2->open_log_count) :
+                                        get_random_u32();
 
-init_log_instance:
-               log_init_pg_hdr(log, page_size, page_size, 1, 1);
+               log_init_pg_hdr(log, 1, 1);
 
-               log_create(log, l_size, rst_info.last_lsn, open_log_count,
-                          wrapped, use_multi_page);
+               log_create(log, log->rst_info.last_lsn, open_log_count, wrapped,
+                          use_multi_page);
 
                ra = log_create_ra(log);
                if (!ra) {
@@ -3916,28 +3899,27 @@ init_log_instance:
         * use the log file. We must use the system page size instead of the
         * default size if there is not a clean shutdown.
         */
-       t32 = le32_to_cpu(rst_info.r_page->sys_page_size);
-       if (page_size != t32) {
-               l_size = orig_file_size;
-               page_size =
-                       norm_file_page(t32, &l_size, t32 == DefaultLogPageSize);
+       t32 = le32_to_cpu(log->rst_info.r_page->sys_page_size);
+       if (log->page_size != t32) {
+               log->l_size = log->orig_file_size;
+               log->page_size = norm_file_page(t32, &log->l_size,
+                                               t32 == DefaultLogPageSize);
        }
 
-       if (page_size != t32 ||
-           page_size != le32_to_cpu(rst_info.r_page->page_size)) {
+       if (log->page_size != t32 ||
+           log->page_size != le32_to_cpu(log->rst_info.r_page->page_size)) {
                err = -EINVAL;
                goto out;
        }
 
        /* If the file size has shrunk then we won't mount it. */
-       if (l_size < le64_to_cpu(ra2->l_size)) {
+       if (log->l_size < le64_to_cpu(ra2->l_size)) {
                err = -EINVAL;
                goto out;
        }
 
-       log_init_pg_hdr(log, page_size, page_size,
-                       le16_to_cpu(rst_info.r_page->major_ver),
-                       le16_to_cpu(rst_info.r_page->minor_ver));
+       log_init_pg_hdr(log, le16_to_cpu(log->rst_info.r_page->major_ver),
+                       le16_to_cpu(log->rst_info.r_page->minor_ver));
 
        log->l_size = le64_to_cpu(ra2->l_size);
        log->seq_num_bits = le32_to_cpu(ra2->seq_num_bits);
@@ -3945,7 +3927,7 @@ init_log_instance:
        log->seq_num_mask = (8 << log->file_data_bits) - 1;
        log->last_lsn = le64_to_cpu(ra2->current_lsn);
        log->seq_num = log->last_lsn >> log->file_data_bits;
-       log->ra_off = le16_to_cpu(rst_info.r_page->ra_off);
+       log->ra_off = le16_to_cpu(log->rst_info.r_page->ra_off);
        log->restart_size = log->sys_page_size - log->ra_off;
        log->record_header_len = le16_to_cpu(ra2->rec_hdr_len);
        log->ra_size = le16_to_cpu(ra2->ra_len);
@@ -4045,7 +4027,7 @@ find_oldest:
        log->current_avail = current_log_avail(log);
 
        /* Remember which restart area to write first. */
-       log->init_ra = rst_info.vbo;
+       log->init_ra = log->rst_info.vbo;
 
 process_log:
        /* 1.0, 1.1, 2.0 log->major_ver/minor_ver - short values. */
@@ -4105,7 +4087,7 @@ process_log:
        log->client_id.seq_num = cr->seq_num;
        log->client_id.client_idx = client;
 
-       err = read_rst_area(log, &rst, &ra_lsn);
+       err = read_rst_area(log, &rst, &checkpt_lsn);
        if (err)
                goto out;
 
@@ -4114,9 +4096,8 @@ process_log:
 
        bytes_per_attr_entry = !rst->major_ver ? 0x2C : 0x28;
 
-       checkpt_lsn = le64_to_cpu(rst->check_point_start);
-       if (!checkpt_lsn)
-               checkpt_lsn = ra_lsn;
+       if (rst->check_point_start)
+               checkpt_lsn = le64_to_cpu(rst->check_point_start);
 
        /* Allocate and Read the Transaction Table. */
        if (!rst->transact_table_len)
@@ -4330,23 +4311,20 @@ check_attr_table:
        lcb = NULL;
 
 check_attribute_names2:
-       if (!rst->attr_names_len)
-               goto trace_attribute_table;
-
-       ane = attr_names;
-       if (!oatbl)
-               goto trace_attribute_table;
-       while (ane->off) {
-               /* TODO: Clear table on exit! */
-               oe = Add2Ptr(oatbl, le16_to_cpu(ane->off));
-               t16 = le16_to_cpu(ane->name_bytes);
-               oe->name_len = t16 / sizeof(short);
-               oe->ptr = ane->name;
-               oe->is_attr_name = 2;
-               ane = Add2Ptr(ane, sizeof(struct ATTR_NAME_ENTRY) + t16);
-       }
-
-trace_attribute_table:
+       if (rst->attr_names_len && oatbl) {
+               struct ATTR_NAME_ENTRY *ane = attr_names;
+               while (ane->off) {
+                       /* TODO: Clear table on exit! */
+                       oe = Add2Ptr(oatbl, le16_to_cpu(ane->off));
+                       t16 = le16_to_cpu(ane->name_bytes);
+                       oe->name_len = t16 / sizeof(short);
+                       oe->ptr = ane->name;
+                       oe->is_attr_name = 2;
+                       ane = Add2Ptr(ane,
+                                     sizeof(struct ATTR_NAME_ENTRY) + t16);
+               }
+       }
+
        /*
         * If the checkpt_lsn is zero, then this is a freshly
         * formatted disk and we have no work to do.
@@ -5189,7 +5167,7 @@ out:
        kfree(oatbl);
        kfree(dptbl);
        kfree(attr_names);
-       kfree(rst_info.r_page);
+       kfree(log->rst_info.r_page);
 
        kfree(ra);
        kfree(log->one_page_buf);