/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Use is subject to license terms.

 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <mdb/mdb_modapi.h>

#include <sys/types.h>

#include <vm/page.h>

#include <sys/thread.h>

#include <sys/swap.h>

#include <sys/memlist.h>

/*

 * Page walker.

 * By default, this will walk all pages in the system.  If given an

 * address, it will walk all pages belonging to the vnode at that

 * address.

 */

/*

 * page_walk_data

 *

 * pw_hashleft is set to -1 when walking a vnode's pages, and holds the

 * number of hash locations remaining in the page hash table when

 * walking all pages.

 *

 * The astute reader will notice that pw_hashloc is only used when

 * reading all pages (to hold a pointer to our location in the page

 * hash table), and that pw_first is only used when reading the pages

 * belonging to a particular vnode (to hold a pointer to the first

 * page).  While these could be combined to be a single pointer, they

 * are left separate for clarity.

 */

typedef struct page_walk_data {

	long		pw_hashleft;

	void		**pw_hashloc;

	uintptr_t	pw_first;

} page_walk_data_t;

int

page_walk_init(mdb_walk_state_t *wsp)

{

	page_walk_data_t	*pwd;

	void	**ptr;

	size_t	hashsz;

	vnode_t	vn;

	if (wsp->walk_addr == NULL) {

		/*

		 * Walk all pages

		 */

		if ((mdb_readvar(&ptr, "page_hash") == -1) ||

		    (mdb_readvar(&hashsz, "page_hashsz") == -1) ||

		    (ptr == NULL) || (hashsz == 0)) {

			mdb_warn("page_hash, page_hashsz not found or invalid");

			return (WALK_ERR);

		}

		/*

		 * Since we are walking all pages, initialize hashleft

		 * to be the remaining number of entries in the page

		 * hash.  hashloc is set the start of the page hash

		 * table.  Setting the walk address to 0 indicates that

		 * we aren't currently following a hash chain, and that

		 * we need to scan the page hash table for a page.

		 */

		pwd = mdb_alloc(sizeof (page_walk_data_t), UM_SLEEP);

		pwd->pw_hashleft = hashsz;

		pwd->pw_hashloc = ptr;

		wsp->walk_addr = 0;

	} else {

		/*

		 * Walk just this vnode

		 */

		if (mdb_vread(&vn, sizeof (vnode_t), wsp->walk_addr) == -1) {

			mdb_warn("unable to read vnode_t at %#lx",

			    wsp->walk_addr);

			return (WALK_ERR);

		}

		/*

		 * We set hashleft to -1 to indicate that we are

		 * walking a vnode, and initialize first to 0 (it is

		 * used to terminate the walk, so it must not be set

		 * until after we have walked the first page).  The

		 * walk address is set to the first page.

		 */

		pwd = mdb_alloc(sizeof (page_walk_data_t), UM_SLEEP);

		pwd->pw_hashleft = -1;

		pwd->pw_first = 0;

		wsp->walk_addr = (uintptr_t)vn.v_pages;

	}

	wsp->walk_data = pwd;

	return (WALK_NEXT);

}

int

page_walk_step(mdb_walk_state_t *wsp)

{

	page_walk_data_t	*pwd = wsp->walk_data;

	page_t		page;

	uintptr_t	pp;

	pp = wsp->walk_addr;

	if (pwd->pw_hashleft < 0) {

		/* We're walking a vnode's pages */

		/*

		 * If we don't have any pages to walk, we have come

		 * back around to the first one (we finished), or we

		 * can't read the page we're looking at, we are done.

		 */

		if (pp == NULL || pp == pwd->pw_first)

			return (WALK_DONE);

		if (mdb_vread(&page, sizeof (page_t), pp) == -1) {

			mdb_warn("unable to read page_t at %#lx", pp);

			return (WALK_ERR);

		}

		/*

		 * Set the walk address to the next page, and if the

		 * first page hasn't been set yet (i.e. we are on the

		 * first page), set it.

		 */

		wsp->walk_addr = (uintptr_t)page.p_vpnext;

		if (pwd->pw_first == NULL)

			pwd->pw_first = pp;

	} else if (pwd->pw_hashleft > 0) {

		/* We're walking all pages */

		/*

		 * If pp (the walk address) is NULL, we scan through

		 * the page hash table until we find a page.

		 */

		if (pp == NULL) {

			/*

			 * Iterate through the page hash table until we

			 * find a page or reach the end.

			 */

			do {

				if (mdb_vread(&pp, sizeof (uintptr_t),

				    (uintptr_t)pwd->pw_hashloc) == -1) {

					mdb_warn("unable to read from %#p",

					    pwd->pw_hashloc);

					return (WALK_ERR);

				}

				pwd->pw_hashleft--;

				pwd->pw_hashloc++;

			} while (pwd->pw_hashleft && (pp == NULL));

			/*

			 * We've reached the end; exit.

			 */

			if (pp == NULL)

				return (WALK_DONE);

		}

		if (mdb_vread(&page, sizeof (page_t), pp) == -1) {

			mdb_warn("unable to read page_t at %#lx", pp);

			return (WALK_ERR);

		}

		/*

		 * Set the walk address to the next page.

		 */

		wsp->walk_addr = (uintptr_t)page.p_hash;

	} else {

		/* We've finished walking all pages. */

		return (WALK_DONE);

	}

	return (wsp->walk_callback(pp, &page, wsp->walk_cbdata));

}

void

page_walk_fini(mdb_walk_state_t *wsp)

{

	mdb_free(wsp->walk_data, sizeof (page_walk_data_t));

}

/* Summary statistics of pages */

typedef struct memstat {

	struct vnode    *ms_kvp;	/* Cached address of kernel vnode */

	struct vnode    *ms_zvp;	/* Cached address of zio vnode    */

	uint64_t	ms_kmem;	/* Pages of kernel memory	  */

	uint64_t	ms_anon;	/* Pages of anonymous memory	  */

	uint64_t	ms_vnode;	/* Pages of named (vnode) memory  */

	uint64_t	ms_exec;	/* Pages of exec/library memory	  */

	uint64_t	ms_cachelist;	/* Pages on the cachelist (free)  */

	uint64_t	ms_total;	/* Pages on page hash		  */

} memstat_t;

#define	MS_PP_ISKAS(pp, stats)				\

	(((pp)->p_vnode == (stats)->ms_kvp) ||		\

	    (((stats)->ms_zvp != NULL) && ((pp)->p_vnode == (stats)->ms_zvp)))

/*

 * Summarize pages by type; called from page walker.

 */

/* ARGSUSED */

static int

memstat_callback(page_t *page, page_t *pp, memstat_t *stats)

{

	struct vnode vn, *vp;

	uintptr_t ptr;

	/* read page's vnode pointer */

	if ((ptr = (uintptr_t)(pp->p_vnode)) != NULL) {

		if (mdb_vread(&vn, sizeof (vnode_t), ptr) == -1) {

			mdb_warn("unable to read vnode_t at %#lx",

			    ptr);

			return (WALK_ERR);

		}

		vp = &vn;

	} else

		vp = NULL;

	if (PP_ISFREE(pp))

		stats->ms_cachelist++;

	else if (vp && IS_SWAPFSVP(vp))

		stats->ms_anon++;

	else if (MS_PP_ISKAS(pp, stats))

		stats->ms_kmem++;

	else if (vp && (((vp)->v_flag & VVMEXEC)) != 0)

		stats->ms_exec++;

	else

		stats->ms_vnode++;

	stats->ms_total++;

	return (WALK_NEXT);

}

/* ARGSUSED */

int

memstat(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)

{

	ulong_t pagesize;

	pgcnt_t total_pages;

	memstat_t stats;

	memstat_t unused_stats;

	GElf_Sym sym;

	bzero(&stats, sizeof (memstat_t));

	bzero(&unused_stats, sizeof (memstat_t));

	if (argc != 0 || (flags & DCMD_ADDRSPEC))

		return (DCMD_USAGE);

	/* Grab base page size */

	if (mdb_readvar(&pagesize, "_pagesize") == -1) {

		mdb_warn("unable to read _pagesize");

		return (DCMD_ERR);

	}

	/* Total physical memory */

	if (mdb_readvar(&total_pages, "total_pages") == -1) {

		mdb_warn("unable to read total_pages");

		return (DCMD_ERR);

	}

	/* Artificially limited memory */

	if (mdb_readvar(&physmem, "physmem") == -1) {

		mdb_warn("unable to read physmem");

		return (DCMD_ERR);

	}

	/* read kernel vnode pointer */

	if (mdb_lookup_by_obj(MDB_OBJ_EXEC, "kvp",

		mdb_warn("unable to read kvp");

		return (DCMD_ERR);

	}

	stats.ms_kvp = (struct vnode *)(uintptr_t)sym.st_value;

	/*

	 * Read the zio vnode pointer.  It may not exist on all kernels, so it

	 * it isn't found, it's not a fatal error.

	 */

	if (mdb_lookup_by_obj(MDB_OBJ_EXEC, "zvp",

		stats.ms_zvp = NULL;

	} else {

		stats.ms_zvp = (struct vnode *)(uintptr_t)sym.st_value;

	}

	/* Walk page structures, summarizing usage */

	if (mdb_walk("page", (mdb_walk_cb_t)memstat_callback,

		mdb_warn("can't walk pages");

		return (DCMD_ERR);

	}

	/* read unused pages vnode */

	if (mdb_lookup_by_obj(MDB_OBJ_EXEC, "unused_pages_vp",

		mdb_warn("unable to read unused_pages_vp");

		return (DCMD_ERR);

	}

	unused_stats.ms_kvp = (struct vnode *)(uintptr_t)sym.st_value;

	/* Find unused pages */

	if (mdb_walk("page", (mdb_walk_cb_t)memstat_callback,

		mdb_warn("can't walk pages");

		return (DCMD_ERR);

	}

	/*

	 * If physmem != total_pages, then the administrator has limited the

	 * number of pages available in the system.  In order to account for

	 * this, we reduce the amount normally attributed to the page cache.

	 */

	stats.ms_vnode -= unused_stats.ms_kmem;

	stats.ms_total -= unused_stats.ms_kmem;

#define	MS_PCT_TOTAL(x)	(((5 * total_pages) + ((x) * 1000ull))) / \

		((physmem) * 10)

	mdb_printf("Page Summary                Pages                MB"

	    "  %%Tot\n");

	mdb_printf("------------     ----------------  ----------------"

	mdb_printf("Kernel           %16llu  %16llu  %3llu%%\n",

	    stats.ms_kmem,

	    (uint64_t)stats.ms_kmem * pagesize / (1024 * 1024),

	    MS_PCT_TOTAL(stats.ms_kmem));

	mdb_printf("Anon             %16llu  %16llu  %3llu%%\n",

	    stats.ms_anon,

	    (uint64_t)stats.ms_anon * pagesize / (1024 * 1024),

	    MS_PCT_TOTAL(stats.ms_anon));

	mdb_printf("Exec and libs    %16llu  %16llu  %3llu%%\n",

	    stats.ms_exec,

	    (uint64_t)stats.ms_exec * pagesize / (1024 * 1024),

	    MS_PCT_TOTAL(stats.ms_exec));

	mdb_printf("Page cache       %16llu  %16llu  %3llu%%\n",

	    stats.ms_vnode,

	    (uint64_t)stats.ms_vnode * pagesize / (1024 * 1024),

	    MS_PCT_TOTAL(stats.ms_vnode));

	mdb_printf("Free (cachelist) %16llu  %16llu  %3llu%%\n",

	    stats.ms_cachelist,

	    (uint64_t)stats.ms_cachelist * pagesize / (1024 * 1024),

	    MS_PCT_TOTAL(stats.ms_cachelist));

	mdb_printf("\nTotal            %16lu  %16lu\n",

	    physmem,

	    (uint64_t)physmem * pagesize / (1024 * 1024));

	if (physmem != total_pages) {

		mdb_printf("Physical         %16lu  %16lu\n",

		    total_pages,

		    (uint64_t)total_pages * pagesize / (1024 * 1024));

	}

#undef MS_PCT_TOTAL

	return (DCMD_OK);

}

int

page(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)

{

	page_t	p;

	if (!(flags & DCMD_ADDRSPEC)) {

		if (mdb_walk_dcmd("page", "page", argc, argv) == -1) {

			mdb_warn("can't walk pages");

			return (DCMD_ERR);

		}

		return (DCMD_OK);

	}

	if (DCMD_HDRSPEC(flags)) {

		mdb_printf("%<u>%?s %?s %16s %8s %3s %3s %2s %2s %2s%</u>\n",

		    "PAGE", "VNODE", "OFFSET", "SELOCK",

		    "LCT", "COW", "IO", "FS", "ST");

	}

	if (mdb_vread(&p, sizeof (page_t), addr) == -1) {

		mdb_warn("can't read page_t at %#lx", addr);

		return (DCMD_ERR);

	}

	mdb_printf("%0?lx %?p %16llx %8x %3d %3d %2x %2x %2x\n",

	    addr, p.p_vnode, p.p_offset, p.p_selock, p.p_lckcnt, p.p_cowcnt,

	    p.p_iolock_state, p.p_fsdata, p.p_state);

	return (DCMD_OK);

}

int

swap_walk_init(mdb_walk_state_t *wsp)

{

	void	*ptr;

	if ((mdb_readvar(&ptr, "swapinfo") == -1) || ptr == NULL) {

		mdb_warn("swapinfo not found or invalid");

		return (WALK_ERR);

	}

	wsp->walk_addr = (uintptr_t)ptr;

	return (WALK_NEXT);

}

int

swap_walk_step(mdb_walk_state_t *wsp)

{

	uintptr_t	sip;

	struct swapinfo	si;

	sip = wsp->walk_addr;

	if (sip == NULL)

		return (WALK_DONE);

	if (mdb_vread(&si, sizeof (struct swapinfo), sip) == -1) {

		mdb_warn("unable to read swapinfo at %#lx", sip);

		return (WALK_ERR);

	}

	wsp->walk_addr = (uintptr_t)si.si_next;

	return (wsp->walk_callback(sip, &si, wsp->walk_cbdata));

}

int

swapinfof(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)

{

	struct swapinfo	si;

	char		*name;

	if (!(flags & DCMD_ADDRSPEC)) {

		if (mdb_walk_dcmd("swapinfo", "swapinfo", argc, argv) == -1) {

			mdb_warn("can't walk swapinfo");

			return (DCMD_ERR);

		}

		return (DCMD_OK);

	}

	if (DCMD_HDRSPEC(flags)) {

		mdb_printf("%<u>%?s %?s %9s %9s %s%</u>\n",

		    "ADDR", "VNODE", "PAGES", "FREE", "NAME");

	}

	if (mdb_vread(&si, sizeof (struct swapinfo), addr) == -1) {

		mdb_warn("can't read swapinfo at %#lx", addr);

		return (DCMD_ERR);

	}

	name = mdb_alloc(si.si_pnamelen, UM_SLEEP | UM_GC);

	if (mdb_vread(name, si.si_pnamelen, (uintptr_t)si.si_pname) == -1)

		name = "*error*";